Open Collections

UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

Western spruce budworm : behavior and monitoring with sex-pheromone traps Sweeney, Jonathan David 1987

Your browser doesn't seem to have a PDF viewer, please download the PDF to view this item.

Item Metadata

Download

Media
831-UBC_1987_A1 S98.pdf [ 11.09MB ]
Metadata
JSON: 831-1.0302137.json
JSON-LD: 831-1.0302137-ld.json
RDF/XML (Pretty): 831-1.0302137-rdf.xml
RDF/JSON: 831-1.0302137-rdf.json
Turtle: 831-1.0302137-turtle.txt
N-Triples: 831-1.0302137-rdf-ntriples.txt
Original Record: 831-1.0302137-source.json
Full Text
831-1.0302137-fulltext.txt
Citation
831-1.0302137.ris

Full Text

WESTERN SPRUCE BUDWORM: BEHAVIOR AND MONITORING WITH SEX-PHEROMONE TRAPS By JONATHAN DAVID SWEENEY B.Sc. (Honors), Simon Fraser University, 1979 A THESIS SUBMITTED IN THE REQUIREMENTS DOCTOR OF PARTIAL FULFILLMENT OF FOR THE DEGREE OF PHILOSOPHY i n THE FACULTY OF GRADUATE STUDIES (Department of Forest Sciences) We accept t h i s thesis as conforming to the required standard THE UNIVERSITY OF BRITISH COLUMBIA October 1987 ® Jonathan David Sweeney, 1987 In presenting this thesis in partial fulfilment of the requirements for an advanced degree at the University of British Columbia, I agree that the Library shall make it freely available for reference and study. I further agree that permission for extensive copying of this thesis for scholarly purposes may be granted by the head of my department or by his or her representatives. It is understood that copying or publication of this thesis for financial gain shall not be allowed without my written permission. Department of F o r e s t S c i e n c e The University of British Columbia 1956 Main Mall Vancouver, Canada V6T 1Y3 Date O c t o b e r 1 4 1 9 8 7 DE-6(3/81) i i ABSTRACT The main objectives of t h i s thesis were to: determine the roles of the minor components, 89/11 (E/Z') 1 1-tetradecenyl acetate (AC) and 85/15 (E/Z) 11-tetradecenol (OH), of the sex pheromone of the western spruce budworm, Choristoneura  occidentalis Freeman, in the orientation and pre-copulatory behaviors of the male moth; and, to evaluate various combinations of pheromone concentration, trap design, and maintenance regime for monitoring the budworm. The behavior of the male moths was observed, in a wind tunnel and in the f i e l d , in response to v i r g i n females and to synthetic sex pheromone components, alone and in blends. The pheromones were incorporated into polyvinyl chloride rods at concentrations from 0.00005-0.5% (w:w) and release rates were estimated by gas-liquid chromatography of v o l a t i l e s captured on Porapak-Q. OH contamination in lures of the major component, 92/8 {E/Z)-11-tetradecenal (ALD), and the AC, made i t impossible to determine precisely the effects of either AC, ALD, or ALD+AC on the behavior of the male moth, but s t i l l allowed the testing of blends of ALD+AC+OH which resembled those released by v i r g i n females. The moths were from three sources: a long-established non-diapausing laboratory colony; wild budworms co l l e c t e d near Ashcroft, B.C.; and crosses between laboratory males and wild females (lab-wild). The threshold concentration of ALD necessary to stimulate upwind f l i g h t was between 0.0005 and 0.005%; response peaked at 0.05% and dropped off above this concentration. The net upwind ground speed of f l i g h t decreased s i g n i f i c a n t l y at higher concentrations of ALD in the laboratory moths, and as the moths approached the lure with a l l three populations. In most experiments, the v i r g i n female stimulated a greater percentage of males to contact the lure, and a faster upwind net ground speed of f l i g h t , than did ALD at about the same release rate. AC and OH stimulated response on an electroantennogram, but by themselves were not a t t r a c t i v e to males in the wind tunnel. The addition of OH to 0.05% ALD s i g n i f i c a n t l y decreased the percentages of males locking-on (0.5% OH) and f l y i n g upwind (0.005% OH) in wild and lab-wild moths respectively, and s i g n i f i c a n t l y increased the percentage copulatory attempts of lab-wild males (0.005% OH). In the lab-wild males, a blend of ALD+AC+OH approximating that from a v i r g i n female s i g n i f i c a n t l y increased the percentages of upwind f l i g h t s , lure contacts, and copulatory attempts over those to ALD alone. The t o t a l blend, and not just the major component, affected long range behavior of the male moth. The laboratory males appeared less sensitive to the addition of minor components to 0.05% ALD than did the wild or lab-wild males. The mean t o t a l season's catch/plot in f i v e non-maintained Uni-traps, baited with 0.05% ALD, was s i g n i f i c a n t l y correlated with the number of larvae/m^ foliage in the same generation (r = 0.97), but only when a lower valley plot with very low l a r v a l density was excluded (plot 12). Correlations were s i g n i f i c a n t ( P ^ 0.10) between l a r v a l density/plot in 1985 and the t o t a l moth iv catch/plot (n = 1 trap/plot) in 1984 in sticky traps (r = 0.45) and Uni-traps (r = 0.44) baited with 0.05% ALD and maintained. The l a t t e r c o r r e l a t i o n was s i g n i f i c a n t l y improved (r = 0.67; 0.05) when plot 12 was excluded. The addition of plot basal area/ha or foliage biomass/ha as independent variables s i g n i f i c a n t l y improved the c o e f f i c i e n t of determination for the regression of l a r v a l density/plot in 1985 vs t o t a l seasons catch/plot in 1984, but again only when plot 12 was excluded. Of the trap systems evaluated, the Uni-trap, baited with 0.05% ALD, showed the most promise for monitoring the western spruce budworm, but permanent sample plots w i l l have to be established and followed for several years to determine whether the system can be operational. V TABLE OF CONTENTS Page ABSTRACT i i TABLE OF CONTENTS . .v LIST OF TABLES v i i i LIST OF FIGURES x v i i ACKNOWLEDGEMENTS x x i i INTRODUCTION 1 MATERIALS AND METHODS 14 RESEARCH STRATEGY 14 INSECTS 14 PHEROMONES 16 WIND TUNNEL 18 PHEROMONE-MEDIATED BEHAVIOR 19 Electroantennograms 19 Wind tunnel bioassays 21 F i e l d bioassays 24 MONITORING WITH PHEROMONE TRAPS 27 Factors a f f e c t i n g catches ...27 A. Age of lures 27 B. Trap height and proximity to foliage 27 C. Trap design 29 Comparisons of designs 29 E f f i c i e n c y 31 Design, pheromone concentration and maintenance ...34 Correlating catch with l a r v a l density 37 v i A. Larval densities 37 B. Trap catches 39 C. Stand parameters 39 RESULTS 41 PHEROMONE RELEASE RATES 41 PHEROMONE-MEDIATED BEHAVIOR 43 Electroantennograms 43 Wind tunnel bioassays ...51 A. Response vs ALD concentration 51 Percentage response 51 Temporal response 56 B. The roles of minor components .64 Percentage response 64 Temporal response 74 F i e l d bioassays 78 A. Trap catch vs ALD concentration 78 B. Comparison of blends 83 MONITORING WITH PHEROMONE TRAPS 87 Factors a f f e c t i n g catches 87 A. Age of lures 87 B. Trap height and proximity to foliage 90 C. Trap design 90 Comparisons of designs 90 E f f i c i e n c y 93 Design, pheromone concentration and maintenance ....99 Correlating catch with l a r v a l density 104 A. Estimating l a r v a l densities 104 v i i B. Trap catch vs l a r v a l density in the same generation 105 C. Trap catch vs l a r v a l density in the following generation 107 DISCUSSION 115 PHEROMONE-MEDIATED BEHAVIOR 115 Electrophysiological responses 115 Behavioral response vs ALD concentration 116 The roles of minor components 118 Variation in response 120 F i e l d bioassays 123 MONITORING WITH PHEROMONE TRAPS 125 Factors a f f e c t i n g trap catches 125 A. Height and proximity to foliage 125 B. Interference . 128 C. E f f i c i e n c y 129 Predicting population trends 132 CONCLUSIONS 142 FUTURE RESEARCH 145 REFERENCES 147 APPENDIX I. Age of the v i r g i n female vs trap catch 164 APPENDIX I I . Pheromone-mediated behavior -additional tables 166 APPENDIX I I I . Diurnal p e r i o d i c i t y of male moth response to sex pheromone 177 APPENDIX IV. Monitoring with pheromone traps -additional tables and figures 180 APPENDIX V. Mark-release-recapture study 195 v i i i LIST OF TABLES Page Table 1 Table 2 Table 3, Table 4 Table 5, The response of western spruce budworm male moths (laboratory) to a range of concentrations of ALD, compared with response to two v i r g i n females. A l l concentrations were formulated in 5 X 3 mm pvc rods , 52 The response of western spruce budworm male moths (wild) to a range of concentrations of ALD, compared with response to two v i r g i n females. A l l concentrations were formulated in 5 X 3 mm pvc rods , 53 The response of western spruce budworm male moths (lab-wild) to a range of concentrations of ALD, compared with response to two v i r g i n females. A l l concentrations were formulated in 5 X 3 mm pvc rods 54 The temporal responses of western spruce budworm adult males (laboratory) to a range of concentrations of ALD in a wind tunnel. Responses were compared with those to a v i r g i n female and a blank control. Due to the low number of responders, data from the CONTROL, and ALD concentrations less than 0.005% were not included in the ANOVA or means tests, except for the variable of R-TO. A l l concentrations were formulated in 5 X 3 mm pvc rods , 57 The temporal responses of western spruce budworm adult males (wild) to a range of concentrations of ALD in a wind tunnel. Responses were compared with those to a v i r g i n female and a blank cont r o l . Due to the low number of responders, data from the CONTROL, and ALD concentrations less than 0.005% were not included in the ANOVA or means tests, except for the variable of R-TO. A l l concentrations were formulated in 5 X 3 mm pvc rods 58 ix Table 6. The temporal responses of western spruce budworm adult males (lab-wild) to a range of concentrations of ALD in a wind tunnel. Responses were compared with those to a v i r g i n female and a blank control. Due to the low number of responders, data from the CONTROL, and ALD concentrations less than 0.005% were not included in the ANOVA or means tests, except for the variable of R-TO. A l l concentrations were formulated in 5 X 3 mm pvc rods 59 Table 7. The net ground speed of f l i g h t of adult male western spruce budworm (laboratory) in response to a range of concentrations of ALD in a wind tunnel. Speed was measured in three sections of the tunnel and was averaged from the s t a r t of stationary zig-zag (LO-T) and the st a r t of upwind f l i g h t (UF-T). Due to the low number of responders, data from ALD concentrations less than 0.005% were not used in the ANOVA or means tes t s . A l l concentrations were formulated in 5 X 3 mm pvc rods 60 Table 8. The net ground speed of f l i g h t of adult male western spruce budworm (wild) in response to a range of concentrations of ALD in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the start of stationary zig-zag (LO-T) and the start of upwind f l i g h t (UF-T). Due to the low number of responders, data from ALD concentrations less than 0.005% were not used in the ANOVA or means tests. A l l concentrations were formulated in 5 X 3 mm pvc rods 61 Table 9. The net ground speed of f l i g h t of adult male western spruce budworm (lab-wild) in response to a range of concentrations of ALD in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the start of stationary zig-zag (LO-T) and the start of upwind f l i g h t (UF-T). Due to the low number of responders, data from ALD concentrations less than 0.005% were not used in the ANOVA or means tes t s . A l l concentrations were formulated in 5 X 3 mm pvc rods 62 X Table 10. Table 11. Table 12. Table 13. Table 14. Preliminary observations showing the effect of ALD concentration on net upwind ground speed of f l y i n g western spruce budworm male moths (laboratory) in a wind tunnel. Pheromone was diluted in n-heptane and added in s p e c i f i c amounts to a 2 cm2 disc of f i l t e r paper The ef f e c t on the response of western spruce budworm male moths (laboratory) in a wind tunnel, of adding 0.5% AC, or 0.5% OH, or both, to 0.05% ALD . A l l components were formulated in 5 X 3 mm pvc rods The ef f e c t on the response of western spruce budworm male moths (wild) in a wind tunnel, of adding 0.5% AC, or 0.5% OH, or both, to 0.05% ALD. A l l components were formulated in 5 X 3 mm pvc rods The ef f e c t on the response of western spruce budworm male moths (lab-wild) in a wind tunnel, of adding 0.5% AC, 0.5% OH, or both, to 0.05% ALD. A l l components were formulated in 5 X 3 mm pvc rods 64 67 68 69 The ef f e c t on the response of western spruce budworm male moths (lab-wild) in a wind tunnel, of adding 0.05% AC (two pvc rods, each 6.5 X 3 mm), or 0.05% OH (7 X 3 mm pvc rod), or both, to 0.05% ALD (5 X 3 mm pvc rod). Due to impurities of OH and ALD in the AC lures, the ALD+AC combination was estimated to release the components at about the same rate as a v i r g i n female 72 Table 15, Table 16, The ef f e c t on the response of western spruce budworm male moths (lab-wild) in a wind tunnel, of adding 0.005% AC, or 0.005% OH, or both, to 0.05% ALD. A l l components were formulated in 5 X 3 mm pvc rods The temporal responses of western spruce budworm male moths (lab-wild) to various blends of 0.05% ALD, 0.5% AC and 0.5% OH in a wind tunnel. Responses were compared with those to a v i r g i n female and a blank control lure. Due to the small number of responders, data from AC, OH and the CONTROL were not included in the ANOVA or means tes t s , except for the variable of R-TO. A l l components were formulated in 5 X 3 mm pvc rods 73 ,75 xi Table 17. The temporal responses of western spruce budworm male moths (lab-wild) to various blends of 0.05% ALD (5 X 3 mm pvc rod), 0.05% AC (two pvc rods, each 6.5 X 3 mm), and 0.05% OH (7 X 3 mm pvc rod) in a wind tunnel. Due to impurities of OH and ALD in the AC lures, the ALD+AC combination was estimated to release the components at about the same rate as a v i r g i n female. Responses were compared with those to a v i r g i n female and a blank control lure. Due to the small number of responders, data from AC, OH and the CONTROL were not included in the ANOVA or means tes t s , except for the variable of R-TO 76 Table 18. The temporal responses of western spruce budworm male moths (lab-wild) to various blends of 0.05% ALD, 0.005% AC and 0.005% OH in a wind tunnel. Responses were compared with those to a v i r g i n female and a blank control lure. Due to the small number of responders, data from AC, OH and the CONTROL were not included in the ANOVA or means tests, except for the variable of R-TO. A l l components were formulated in 5 X 3 mm pvc rods 77 Table 19. The net ground speed of f l i g h t of adult male western spruce budworm (lab-wild) in response to blends of 0.05% ALD, 0.5% AC, and 0.5% OH in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the star t of stationary zig-zag (LO-T) and the start of upwind f l i g h t (UF-T). A l l components were formulated in 5 X 3 mm pvc rods 79 Table 20. The net ground speed of f l i g h t of adult male western spruce budworm (lab-wild) in response to blends of 0.05% ALD (5 X 3 mm pvc rod), 0.05% AC (two pvc rods, each 6.5 X 3 mm), and 0.05% OH (7 X 3 mm pvc rod) in a wind tunnel. Due to impurities of OH and ALD in the AC lures, the ALD+AC combination was estimated to release the components at about the same rate as a v i r g i n female. Speed was measured in three sections of the tunnel and averaged from the star t of stationary zig-zag (LO-T) and the start of upwind f l i g h t (UF-T) 80 x i i Table 21. The net ground speed of f l i g h t of adult male western spruce budworm (lab-wild) in response to blends of 0.05% ALD, 0.005% AC, and 0.005% OH in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the start of stationary zig-zag (LO-T) and the star t of upwind f l i g h t (UF-T). A l l components were formulated in 5 X 3 mm pvc rods 81 Table 22. Table 23. Table 24. Table 25. The effect of adding 0 . 0 0 5 - 0 . 5 % AC to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time replicated l a t i n square design (8 X 8) (24-27 July 1984) The effect of adding 0.005-0.5% OH to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time replicated l a t i n square design (8 x 8) (26-30 July 1984) The a c t i v i t y of the minor components, AC, OH, 14:ALD, and 14:AC, of the western spruce budworm pheromone as measured by trap catch in the f i e l d . The components were rated as follows: + = s i g n i f i c a n t l y positive e f f e c t , -s i g n i f i c a n t l y negative e f f e c t , (+) and (-) denote possible but not s i g n i f i c a n t p o s i t i v e and negative e f f e c t s respectively, and 0 = no effect 84 ,85 The effect of adding 0.005% OH, or 0.005% AC, or both, to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time replicated l a t i n square design (7 x 7) (28 July - 3 August 1984) 86 ,88 Table 26. Comparison of high-capacity pheromone traps for western spruce budworm male moths. Five designs were compared in two experiments (A and B) set out in l a t i n squares (4 X 4). Traps were baited with a crude blend of E/Z-11-tetradecenal. The lure was suspended between the fourth and f i f t h funnel of the funnel and half-funnel traps in experiment A; but was suspended just above the c o l l e c t i n g jar in experiment B 91 x i i i Table 27. Table 28. Table 29. Table 30. Table 31. Table 32. Table 33 The e f f i c i e n c y of three high-capacity traps for trapping western spruce budworm male moths in the f i e l d . Each percentage i s a mean of fiv e replicates of ten males approaching within 1 m of the trap The e f f e c t of ALD concentration on e f f i c i e n c y of the Uni-trap for trapping western spruce budworm male moths. Twelve males were released to each treatment in the wind tunnel , The mean catch (n = 8) of western spruce budworm male moths in eight d i f f e r e n t trap systems in each of f i f t e e n p l o t s . The trap systems were a combination of two trap designs (Uni-trap vs Triangular sticky trap), two concentrations of ALD (0.05% vs 0.0005%) in pvc),and two maintenance regimes (traps cleaned every two days (M) vs moths accumulated in trap a l l season (NM)) , Summary of the f a c t o r i a l experiment comparing d i f f e r e n t pheromone trapping systems for the capture of western spruce budworm male moths. The experiment was set out in a l a t i n square and replicated in 15 p l o t s . The s i g n i f i c a n t factors and interactions are marked (*) in each pl o t . Three-way ANOVA on transformed data, (log(y+ D ) , P 4 0.05 , The e f f e c t of estimated basal area/ha and foliage biomass/ha on the relationship between t o t a l seasons catch in Uni-traps, baited with 0.05% ALD, (n = 1 trap/plot) and the mean number of larvae/three branches/ plot in the same generation (beat 1984). Analysis excluded plot 12 (n = 14) The effect of estimated basal area/ha and foliage biomass/ha on the relationship between t o t a l seasons catch in Uni-traps, baited with 0.05% ALD, (n = 1 trap/plot) and the mean number of larvae/three branches/ plot the following year (beat 1985). The analysis excluded plot 12 (n = 14) The r e l a t i v e v a r i a b i l i t y of laboratory, wild, and lab-wild populations of western spruce budworm adult males in response to a range of concentrations of ALD and a v i r g i n female. ... 96 98 100 102 108 1 1 4 167 xiv Table 34 Table 35, Table 36, The temporal responses of western spruce budworm adult males (laboratory) to various blends of 0.05% ALD, 0.5% AC, and 0.5% OH in a wind tunnel. The responses were compared with those to a v i r g i n female and a blank control lure. Due to the small number of responders, data from AC, OH and the CONTROL were not included in the ANOVA or means tests, except for the variable of R-TO. A l l components were formulated in 5 X 3 mm pvc rods , The temporal responses of western spruce budworm adult males (wild) to various blends of 0.05% ALD, 0.5% AC, and 0.5% OH in a wind tunnel. Responses were compared with those to a v i r g i n female and a blank control lure. Due to the small number of responders, data from AC, OH and the CONTROL were not included in the ANOVA or means tests, except for the variable of R-TO. A l l components were formulated in 5 X 3 mm pvc rods , 168 169 The net ground speed of f l i g h t of adult male western spruce budworm (laboratory) in response to blends of 0.05% ALD, 0.5% AC, and 0.5% OH in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the start of stationary zig-zag (LO-T) and the start of upwind f l i g h t (UF-T). A l l components were formulated in 5 X 3 mm pvc rods 170 Table 37. The net ground speed of f l i g h t of adult male western spruce budworm (wild) in response to blends of 0.05% ALD, 0.5% AC, and 0.5% OH in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the start of stationary zig-zag (LO-T) and the start of upwind f l i g h t (UF-T). A l l components were formulated in 5 X 3 mm pvc rods 171 Table 38. The ef f e c t of adding 0.0005-0.005% 14:ALD to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (7 X 7M24-26 July 1984) 172 Table 39. The effect of adding 0.005% 14:AC to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (6 X 6)(24-27 July 1984) 173 XV Table 40. Table 41 Table 42, Table 43. The effect of adding 0.0005% 14:ALD, 0.005% AC, or both, to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (8 X 8) (27-31 July 1984) , 174 The effect of adding 0.005% AC, 0.005% 14:AC, or both, to 0.05% ALD on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (6 X 6M27-30 July 1984) , 175 The effect of adding 0.005% AC, 0.005%OH, 0.005% 14:AC, and 0.0005% 14:ALD, to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l concentrations were formulated an 5 X 3 mm pvc rods. The traps were set out in a time replicated l a t i n square design (11 X 11) (30 July - 13 August 1984) Correlation c o e f f i c i e n t s between t o t a l season's catch/plot (n = 1 trap/plot) in various pheromone trap systems in 1984 and l a r v a l density/plot in 1984. A l l traps were baited with ALD 176 183 Table 44, Table 45, Correlation c o e f f i c i e n t s between the mean t o t a l season's catch/plot (n = 5 traps/plot) in 1984 and l a r v a l density/plot in 1984. Traps were baited with 0.05% ALD Correlation c o e f f i c i e n t s between t o t a l season's catch/plot (n = 1 trap/plot) in various pheromone trap systems in 1984 and l a r v a l density/plot in 1985. A l l traps were baited with ALD , 184 185 Table 46. Correlation c o e f f i c i e n t s between the mean t o t a l season's catch/plot (n = 5 traps/plot) in 1984 and l a r v a l density/plot in 1985. Traps were baited with 0.05% ALD 186 xvi Table 47. Summary of mark-release-recapture experiments with the western spruce budworm in the Oregon Jack Creek v a l l e y . Design 1 used ten Uni-traps; design 2 used a grid of 12 Uni-traps and 12 sticky traps; designs 3 used a grid of 24 sticky traps; and design 4 used four l i n e s of five sticky traps each. A l l traps were baited with 0.05% ALD 198 Table 48. The effect of fluorescent powder (dusted) with or without previous capture in a pheromone-baited Uni-trap, on response of western spruce budworm male moths to 0.05% ALD in a wind tunnel 200 Table 49. Effe c t of fluorescent powder (dusted) on the antennal amplitude of western spruce budworm in response to ALD, as measured by the electroantennogram technique .201 xvi i LIST OF FIGURES Page F i g . 1. Chemical structures of the pheromone components of the western spruce budworm. The v i r g i n female emits an average blend of 92/8 (E/Z) 11-tetradecenal (ALD), 89/11 (E/Z) 11-tetra-decenyl acetate and 85/15 (E/zT 11-tetradecenol in a r e l a t i v e r a t i o of about 10:3:6 respectively, plus tetradecanal and tetradecanyl acetate at about 1-2% of the ALD ( S i l k et a l . 1982) 5 F i g . 2. Triangular sticky trap made from a 2 L milk carton and coated on the inside with "Stikem Special" 25 F i g . 3. The high-capacity Uni-trap ...28 F i g . 4. High-capacity pheromone trap designs. The funnel traps were modified from a Lindgren funnel trap (F)(Lindgren 1983). MF = Mini-funnel, HMF = Half-mini-funnel, HF = Half-funnel, K = Kendall trap, L = lure 30 F i g . 5. The high-capacity Multi-Pher trap 33 F i g . 6. Map showing the location-of the f i e l d studies. Eight sample plots were located in the Oregon Jack Creek valley (plots 1,3,4,11,12,13,14, and 15), and seven along Barnes Lake road (plots 2,5,6,7,8,9, and 10). A l l f i e l d bioassays comparing pheromone blends were conducted in the Oregon Jack Creek v a l l e y 36 F i g . 7. Mean peak amplitude (±S.E.) of western spruce budworm adult male EAG response to a range of concentrations of ALD, AC, and OH. A. Laboratory males (n = 19). B. Wild males (n = 20). Each male was tested with a l l components and concentrations 44 F i g . 8. Regressions of peak amplitude of EAG response ( /y~) of western spruce budworm adult males vs ALD concentration (Log x (10^)). A. Labora-tory males (n = 19/concentration). B. Wild males (n = 20/concentration). The regressions are each s i g n i f i c a n t (P ^ 0.001) but are not s i g n i f i c a n t l y d i f f e r e n t from each other (P ^ 0.05) 45 xvi i i F i g . 9. Mean lag (± S.E.) following response (EAG) of western spruce budworm adult males to a range of concentrations of ALD, AC, and OH. A. Labor-atory males (n = 19). B. Wild males (n = 20). Each male was tested to a l l components and concentrations 46 Fi g . 10. Regressions of lag ( 7y~ ) y_s ALD concentration (Log x (10^)) following antennal response (EAG) of western spruce budworm adult males. A. Laboratory males (n = 19/concentration). B. Wild males (n =•20/concentration). The regressions are each s i g n i f i c a n t (P ^. 0.001) 48 Fig . 11. Percentage of western spruce budworm adult male antennae responding to a range of concentrations of ALD, AC and OH on the EAG. A. Laboratory males (n = 19). B. Wild males (n = 20). Each male was tested to a l l compon-ents and concentrations ' 49 Fi g . 12. Mean EAG response of western spruce budworm male antennae (lab-wild; n = 19) to blends of 0.05% ALD, 0.5% AC, and 0.5% OH. A. = amplitude vs blend. B. = lag vs blend. Each antennae was exposed to a l l treatments; d i f f e r e n t l e t t e r s indicate s i g n i f i c a n t differences (ANOVA for repeated measures and Newman-Keuls, <* = 0.05) 50 Fig . 13. Typical zig-zag upwind f l i g h t path of a male western spruce budworm moth in response to pheromone (0.05% ALD) in the wind tunnel. The f l i g h t was videotaped, played back frame by frame, and the f l i g h t path traced on a piece of acetate placed over the t e l e v i s i o n monitor. Each "x" represents a 1 s i n t e r v a l . Windspeed = 0.40 cm/s. Note the much f l a t t e r zig-zags within 10-20 cm of the lure 66 Fi g . 14. Mean catch/trap (+.S.E.) of western spruce budworm moths in sticky traps baited with ALD at concentrations from 0.0005% to 0.5%, or two v i r g i n female budworm/trap. The regression of catch/trap vs ALD concentration (log(x * 10 4)) was s i g n i f i c a n t (P ^  0.01; r 2- = 0.37). Different l e t t e r s adjacent to the means denote s i g n i f i c a n t l y d i f f e r e n t trap catch (ANOVA & Newman-Keuls, <* = 0.05) 82 X I X F i g . 15 . T h e e f f e c t o f age o f ALD l u r e s ( i n p v c ) on mean c a t c h i n s t i c k y t r a p s ( n = 7 ) . L u r e s were a g e d i n a fume h o o d . A . 0.05% A L D . B . 0.0005% A L D . D i f f e r e n t l e t t e r s a d j a c e n t t o t h e means d e n o t e s i g n i f i c a n t l y d i f f e r e n t t r a p c a t c h (ANOVA & N e w m a n - K e u l s , oi = 0 . 0 5 ) 89 F i g . 16 . E f f e c t o f c u m u l a t i v e c a t c h o f w e s t e r n s p r u c e budworm m a l e m o t h s on t h e e f f i c i e n c y o f t h e s t i c k y t r a p b a i t e d w i t h 0.05% ALD 94 F i g . 17 . G r a p h s s h o w i n g t h e i n t e r a c t i o n b e t w e e n t r a p d e s i g n , p h e r o m o n e r e l e a s e r a t e , a n d m a i n t e n a n c e r e g i m e , f o r t r a p p i n g t h e w e s t e r n s p r u c e budworm. P l o t 6 i s u s e d a s an e x a m p l e . E a c h g r a p h shows mean c a t c h / t r a p (n = 8 ) ( l o g y ) o f t h e d i f f e r e n t t r e a t m e n t s . A . S t i c k y t r a p s , B . U n i - t r a p s , C . T r a p s m a i n t a i n e d , D . T r a p s n o t m a i n t a i n e d . W i t h i n e a c h p l o t , d i f f e r e n t l e t t e r s a d j a c e n t t o means i n d i c a t e s s i g n i f i c a n t d i f f e r e n c e s (ANOVA a n d N e w m a n - K e u l s , oc = 0 . 0 5 ) . M = M a i n t a i n e d , NM = N o n m a i n t a i n e d 103 F i g . 18 . T h e mean t o t a l s e a s o n ' s c a t c h / p l o t i n n o n -m a i n t a i n e d (NM) U n i - t r a p s (n = 5 t r a p s / p l o t ) v s t h e number o f l a r v a e / m 2 f o l i a g e / p l o t i n t h e same g e n e r a t i o n . R e g r e s s i o n was c a l c u l a t e d by e x c l u d i n g p l o t 12, d e s i g n a t e d by t h e s o l i d s q u a r e 106 F i g . 19 . T h e mean number o f l a r v a e / t h r e e b r a n c h e s / p l o t i n 1985 v s t h e t o t a l 1984 s e a s o n ' s c a t c h / p l o t i n m a i n t a i n e d (M) s t i c k y t r a p s , b a i t e d w i t h 0.05% ALD 1 09 F i g . 2 0 . T h e mean number o f l a r v a e / t h r e e b r a n c h e s / p l o t i n 1985 v s t h e t o t a l 1984 s e a s o n ' s c a t c h / p l o t i n m a i n t a i n e d U n i - t r a p s , b a i t e d w i t h 0.05% A L D . R e g r e s s i o n was c a l c u l a t e d e x c l u d i n g p l o t 12 , d e s i g n a t e d by t h e s o l i d s q u a r e 111 F i g . 2 1 . T h e mean number o f l a r v a e / 1 0 0 new s h o o t s / p l o t i n 1985 v s t h e t o t a l s e a s o n ' s c a t c h i n m a i n t a i n e d s t i c k y t r a p s ( M ) , b a i t e d w i t h 0.05% A L D 112 F i g . 2 2 . P l o t s h o w i n g t h e e f f e c t o f c u m u l a t i v e c a t c h on t h e e f f i c i e n c y o f t h e U n i - t r a p . C u m u l a t i v e c a t c h i n t h e n o n - m a i n t a i n e d U n i - t r a p d r o p p e d o f f r e l a t i v e t o t h e m a i n t a i n e d U n i - t r a p . A c u r v i l i n e a r m o d e l ( r 2 = 0 . 7 3 ) f i t s t h e d a t a b e t t e r t h a n t h e l i n e a r m o d e l ( r 2 = 0 . 6 6 ) 131 XX F i g . 23. Plot showing cumulative catch in maintained and non-maintained sticky traps, r e l a t i v e to cumulative catch in the maintained Uni-trap. A l l traps were baited with 0.05% ALD. Even when maintained, catch in the sticky trap dropped off r e l a t i v e to the Uni-trap at higher cumulative catches 133 F i g . 24. The v a r i a t ion between plots in the r a t i o of trap catch/larval density (log y). A. The t o t a l 1984 season's catch/plot in maintained Uni-traps over the mean number of larvae/three branches/plot in 1984. B. The t o t a l 1984 season's catch in maintained Uni-traps over the number of larvae/ three branches/plot in 1985. Plots 11, 12 were located in the lower end of the Oregon Jack Creek valley while plots 14 and 15 were located in the upper end 136 F i g . 25. The effect of age (days from eclosion) on the attractiveness of v i r g i n female western spruce budworm moths to conspecific male moths, as measured by trap catch in double funnel traps. Catch in traps baited with ALD (50 ug/d in a bubblecap lure) were included as a covariate 165 F i g . 26. Diurnal p e r i o d i c i t y of adult male western spruce budworm response to v i r g i n females (4-6 days from eclosion) and to synthetic pheromone (three 1 ul micropipettes of a crude blend of E/Z 11-tetradecenal in a 2 ml glass v i a l ) as measured in hourly catches in triangular sticky traps. Mean trap catch/hour i s the t o t a l of three traps/treatment/hour, averaged over three nights (18-21 July, 1983). The arrow designates sunset (PST) 178 F i g . 27. The relationship between the mean number of larvae/three branches/plot in the lower crown (n = 50 trees/plot) and the number of larvae/m^ fo l i a g e / p l o t in the mid-crown (n = 25 t r e e s / p l o t ) . A. 1984, B. 1985 . 181 F i g . 28. The r e l a t i o n s h i p between the mean number of larvae/three branches/plot in the lower crown (n = 50 trees/plot) and the number of larvae/100 new shoots/plot in the mid-crown (n = 25 t r e e s / p l o t ) . A. 1984, B. 1985 182 F i g . 29. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 1; B. Plot 2 187 xxi F i g . 30. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 3; B. Plot 4 188 Fi g . 31. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 5; B. Plot 6 189 Fi g . 32. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 7; B. Plot 8 190 Fi g . 33. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 9; B. Plot 10 191 Fi g . 34. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 11; B. Plot 12 192 Fi g . 35. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 13; B. Plot 14 193 Fi g . 36. A. Seasonal p r o f i l e of trap catch of the western spruce budworm in plot 15. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. B. Seasonal tempera-ture p r o f i l e in 1984; the temperature was monitored with a hygrothermograph inside a Stevenson screen located at about 850 m elevation in the Oregon Jack Creek valley 194 xxi i ACKNOWLEDGEMENTS I thank Dr. J.A. McLean, for advice, d i r e c t i o n , and support throughout the development of thi s research; Dr. H. R. MacCarthy, for kindly o f f e r i n g to read and edit the thesis, for improving my writing s t y l e , and for teaching me the value of an outline; Dr. R.F. Shepherd, for providing the 1985 trap catch data, and advice and correspondence on several occasions; Dr. B. van der Kamp, for advice and for allowing me to use his freezer for pheromone storage; Dr. W. Wellington, for suggesting that I p r o f i t from a problem by looking more clos e l y at the effect of Nosema on the budworm, and other advice; Dr. J. Worrall, for his advice and sense of humor; Ms. L. F r i s k i e , for t i r e l e s s rearing of the budworm, f l y i n g moths in the wind tunnel on several occasions, and for general and e f f i c i e n t technical assistance; Mr. D. MacCarthy, for advice on a l l things technical and computer-related, on occasions too numerous to mention; Mr. B. Wong and Mr. J. Emmanuel for assistance in computerized data analysis; Dr. L. Weiler and Dr. B. Morgan of U.B.Cs Department of Chemistry, for providing the pheromones; Dr. J . Robertson and Dr. D. Grisdale, for providing budworms for rearing; Mr. J . Northrop, Ms. L. El-Kassaby, Ms. M. Bapte, Mr. M. Putland, Mr. R. Grieve, Ms. R. Penty, Ms. J . Holman, Ms. J. Landels, Mr. G. Bohnenkamp and Mr. E. Burke, Mr. C. L a i , and Mr. E. Lee, for technical assistance in the laboratory and the f i e l d ; Dr. A. Kozak, Dr. S. Chiyenda, Mr. W. Smith, and Dr. Y. El-Kassaby for s t a t i s t i c a l advice; Dr. P. Marshall, for advice on stand c r u i s i n g data; Dr. xxi i i S. Lindgren for advice and assistance; Dr. D. T a i t , and Mr. R. Wiart, for kindly allowing me to use their HP-plotters; Ms. M. Landels and Mr. P. McCrae for kindly allowing me to work on their property; Dr. L. Gass, for inducing me to think of things from d i f f e r e n t perspectives; Dr. G.G. Wilson for i d e n t i f y i n g a disease in a laboratory colony as being caused by a Nosema sp.; Dr. H. Teh and Ms. P. Kwong, for the use of their hemocytometer; my fellow graduate students for often i n s p i r i n g , research-related discussions and for moral support; the P a c i f i c Forestry Centre for loaning me a Stevenson screen; Mr. P. Putland, Mr. J.P. LaFontaine, and Ms. M. Lemke of Pherotech, for providing assistance and f a c i l i t i e s for the determination of pheromone release rates; and, the B.C. Forest Service d i s t r i c t o f f i c e in Ashcroft, for providing indoor space during the f i e l d season. I also thank the Natural Sciences and Engineering Research Council of Canada, the University of B r i t i s h Columbia, and the Canadian Forestry Service Block grant to Forestry schools, for f i n a n c i a l support. F i n a l l y , I thank my fiancee, Lindsey, and my family and friends for much appreciated moral support. 1 INTRODUCTION The western spruce budworm, Choristoneura occidentalis Freeman (Lepidoptera:Tortricidae), i s a defol i a t o r of Douglas-f i r (Pseudostuga menziesii (Mirb.) Franco) and true f i r s (Abies L.) in western North America (Furniss and Carolin 1977). Local outbreaks may collapse in two years or may last ten years or longer and do not appear to be c y c l i c ; the current infestation in B r i t i s h Columbia started in 1967 (Harris et al. 1985). In B r i t i s h Columbia, the Vancouver and Kamloops forest regions are the most severely affected (Unger 1983). The damages from budworm-caused d e f o l i a t i o n are mainly the loss of height and diameter growth, and t o p - k i l l , but some suppressed trees may be k i l l e d (Alfaro 1986; Alfaro et a l . 1982; C o l l i s and Van Sickle 1978; Shepherd et a l . 1977; Van Sickle e t . a l . 1983). Direct feeding on cones and seeds and on understory regeneration i s often severely damaging (Van Sickle 1987). Alfaro et a l . (1985) estimated a cumulative volume loss of 44% in an 80-year-old stand of Douglas-fir which had been infested by budworm four times. Damage i s usually greater on grand f i r (A. grandis (Dougl.) Lindl.) than on Douglas-fir (Brubaker and Greene 1979; Carolin and Coulter 1975; Williams 1967). To avoid volume losses in high-value stands, i t may be necessary to control the budworm d i r e c t l y . This requires r e l i a b l e methods of population monitoring, and i d e a l l y , a method for predicting the pr o b a b i l i t y of an outbreak occurring one or 2 two years hence to allow time for decisions and planning of control operations (Daterman 1979). Detection and monitoring of budworm with conventional methods of larvae and egg sampling are impractical at low densities, but may be possible with the use of sensitive sex pheromone-baited traps (Sanders 1981a). For example, the use of pheromone-baited traps has extended the known range of the Douglas-fir tussock moth, Orgyia  pseudotsugata (McDunnough) to areas in B r i t i s h Columbia and the western U.S. where i t had not previously been recorded (Livingston and Daterman 1977). Since the i s o l a t i o n and i d e n t i f i c a t i o n of the sex pheromone of the silkworm moth, Bombyx mori (L.)(Butenandt et a l . 1959) 1, there has been extensive research into the i d e n t i f i c a t i o n , synthesis, and application of pheromones in pest management (Birch 1974; Kydonieus and Beroza 1982; Mi t c h e l l 1981; Shorey and McKelvey 1977; and references therein). U n t i l recently, however, there has been r e l a t i v e l y l i t t l e research on the behavior of insects in response to their pheromones. Such studies are necessary i f pheromones are to be used most e f f e c t i v e l y in the control of insect pests (Carde 1979). I n i t i a l l y thought to consist of a single compound s p e c i f i c for a given species, most moth pheromones have since been shown to be sp e c i e s - s p e c i f i c , multicomponent blends of long-chain, unsaturated, c i s (Z) and trans (E) isomers of acetates, alcohols or aldehydes (Roelofs and Carde 1977; Roelofs and Brown 1982; Abstract seen only. 3 S i l v e r s t e i n 1981). In recent y e a r s , there have been many s t u d i e s concerned with understanding the behavior of male moths i n response to s p e c i f i c sex pheromone components and m u l t i -component blends; some examples i n c l u d e the spruce budworm, Ch o r i s t o n e u r a fumiferana ( C l e m e n s ) ( A l f o r d et a l . 1983; Sanders 1984a; S i l k and Kuenen 1986), the Egyptian c o t t o n leafworm, Spodoptera l i t t o r a l i s ( B o i s d . ) ( H a i n e s 1983), the D o u g l a s - f i r tussock moth (Daterman e_t a l . 1976), the O r i e n t a l f r u i t moth, G r a p h o l i t h a molesta (Busck) (Baker and Carde 1979; Baker e_t a l . 1980), the red banded l e a f r o l l e r , A r g y r o t a e n i a v e l u t i n a n a (Walker)(Baker et a l . 1976), the corn earworm, H e l i o t h i s zea (Boddie)(Carpenter and Sparks 1981), the tobacco budworm moth, H. v i r e s c e n s ( F . M V e t t e r and Baker 1983), the redbacked cutworm, Euxoa ochrogaster (Guenee) (Palaniswamy et a_l. 1983), and the cabbage looper, T r i c h o p l u s i a n i (Hiibner) (Linn and Gaston 1981a, 1981b; Linn et a l . 1986). Roelofs and Carde (1977) proposed that multicomponent pheromones c o n s i s t e d of primary components, r e s p o n s i b l e f o r e l i c i t i n g long range (^1m) upwind o r i e n t a t i o n , and secondary components, which i n combination with the primary components s t i m u l a t e c l o s e range behaviors such as l a n d i n g and c o p u l a t i o n . Support f o r t h i s paradigm was found i n the O r i e n t a l f r u i t moth (Carde e_t a l . 1975), the redbanded l e a f r o l l e r (Baker et a l . 1976), the cabbage looper (Linn and Gaston 1981a; 1 9 8 l b ) , and the pine beauty moth, P a n o l i s f lammea ( S c h i f f.) (Bradshaw e_t a l . 1983). However, subsequent s t u d i e s (Baker and Carde" 1979; Baker and R o e l o f s 1981; L i n n et a l . 1986) have suggested, i n s t e a d , 4 that the entire blend of components acts as a unit to e l i c i t both long range (early) and close range (late) behaviors. Linn et a l . (1986) state that the minor components act as an ensemble to enhance the male's response to the major pheromone component(s) and that studies which had e a r l i e r suggested s p e c i f i c roles for individual components or p a r t i a l blends were flawed because they used exaggerated blend ra t i o s or incomplete blends. The sex pheromone of the western spruce budworm i s a blend of 92/8 (E/Z) 11-tetradecenal (ALD); 89/11 (E/Z) 11-tetradecenyl acetate (AC); and 85/15 (E/Z) 11-tetradecenol (OH), in a r e l a t i v e r a t i o of about 10:3:6 respectively, plus tetradecanal (14:ALD) and tetradecanyl acetate (14:AC) at about 1-2% of the ALD (Silk et a l . 1982; Cory et a l . l982)(Fig. 1). Weatherston et a_l. (1971) demonstrated that male western spruce budworm moths were attracted to E 11-tetradecenal in the f i e l d . Cory et a l . (1982) found that their trap catch was increased by adding 3-8% of the Z isomer to E 11-tetradecenal but was not affected by adding AC or OH, alone or together. S i m i l a r l y , in sympatric populations of C. occidentalis and C. retiniana (Walsingham), Liebhold and Volney (1985) found the percentage of C. occidentalis caught in ALD-baited sticky traps was not affected by the addition of low concentrations of AC and OH. Cory et a l . (1982) suggested that AC and OH were unnecessary for long range a t t r a c t i o n of males but could possibly have close range behavioral roles not detectable by trapping bioassays. However, in wind tunnel experiments using release rates 5 E - l l - t e t r a d e c e n a l Z - l l - t e t r a d e c e n a l . E - l l - t e t r a d e c e n y l a c e t a t e Z ^ - l l - t e t r a d e c e n y l a c e t a t e CH- OH E - l l - t e t r a d e c e n o l CH 9OH Z - l l - t e t r a d e c e n o l t e t r a d e c a n a l t e t r a d e c a n y l a c e t a t e Fig. 1. Chemical structures of the pheromone components of the western spruce budworm. The virgin female emits an average blend of 92/8 (E/Z) 11-tetradecenal (ALD), 89/11 (E/Z) 11-tetra-decenyl acetate and 85/15 (E/Z) 11-tetradecenol in a relative ratio of about 10:3:6 respectively, plus tetradecanal and tetradecanyl acetate at about 1-2% of the ALD (Silk et a l . 1982). 6 approximating those of a v i r g i n female, Alford and S i l k (1984) found that percentage upwind f l i g h t to the ALD lure was s i g n i f i c a n t l y increased by adding AC, OH, or both; neither AC nor OH were a t t r a c t i v e by themselves. The blend of ALD:AC:OH (10:10:50 ng on f i l t e r paper) induced as much upwind f l i g h t as a v i r g i n female but s i g n i f i c a n t l y fewer landing and copulatory attempts at the lure (Alford and S i l k 1984). It was apparent that AC and OH enhanced the orientation response of male western spruce budworm to ALD but no blend induced so complete a behavioral sequence as a v i r g i n female. Alford and S i l k (1984) suggested that their ALD:AC:OH blend ratios were d i f f e r e n t from those emitted from a v i r g i n female because of unequal release rates of the components from f i l t e r paper. Male moths detect sex pheromone with specialized olfactory neurons located inside sensory hairs c a l l e d the s e n s i l l a e trichodea which are on the antennae (Chapman 1982). Adult male spruce budworm have about 2300 s e n s i l l a e trichodea/antenna and each contains f i v e olfactory neurons (Albert and Seabrook 1973). Much of the pheromone transduction process and decoding of the stimuli by the insect's central nervous system (CNS) remains unknown. It is thought that pheromone molecules d i f f u s e through tiny pores in the sensory hairs and bind with accepter proteins on the dendritic membrane. This binding causes a conformational change in the membrane and the opening of ion channels which in turn causes a depolarization of the c e l l membrane and the f i r i n g of a receptor p o t e n t i a l . If the receptor potential i s s u f f i c i e n t l y intense, action potentials are generated in the 7 axon of the olfactory neurons which run d i r e c t l y , without synapses, to the deutocerebrum of the brain (Masson 1984). The pheromone qual i t y and quantity i s then probably decoded by the CNS according to the s p a t i a l and temporal array of action potentials from the responding olfactory neurons (Kaissling 1971; Mustaparta 1984; O'Connell 1986; Payne 1974; Preisner 1986; Seabrook 1978). The electroantennogram technique (EAG) records the summed potentials of a l l the olfactory neurons which respond to a given stimulus and can be used to determine the r e l a t i v e s e n s i t i v i t y of an insect to various pheromone components (Roelofs 1977). It does not reveal how a moth w i l l behave in response to a given compound but i t i s a useful step in screening pheromone components for their possible a c t i v i t y . In the f i r s t part of t h i s thesis, the behavioral roles of ALD, AC, OH, and blends thereof were studied using EAGs, wind tunnel bioassays, and f i e l d trapping bioassays, at release rates bracketing those from a v i r g i n female. Two of the hypotheses tested were: the orientation and pre-mating behavior of the male western spruce budworm moth in response to ALD i s enhanced by the addition of the minor components, AC or OH, alone or together; and that the minor components modify the pre-copulatory behavior of males in response to ALD at close range but do not enhance behavior at long range i.e. at distances greater than 0.5 m from the lure. I hypothesized that the net upwind ground speed of f l i g h t i s inversely related to the 8 concentration of ALD and I also tested Roelofs' (1978) hypothesis that stimulation of f l i g h t upwind to the lure requires pheromone concentrations that are above an activation threshold but below a d i s o r i e n t a t i o n threshold. I was also concerned about the possible differences in behavior between the laboratory colony and wild budworm and therefore compared the pheromone-mediated behavior of laboratory colony males, wild males and males of laboratory-wild crosses. The second part of the thesis focuses on population monitoring using pheromone-baited traps and the various factors that influence trap catch. There are several possible strategies for the use of pheromone traps in population monitoring (Sanders 1986a; Shepherd et a l . 1985). Pheromone traps can be used simply to detect the pest's presence and i t s • d i s t r i b u t i o n , thereby indicating where further sampling may be required. This has been used for the forest tent c a t e r p i l l a r , Malacosoma d i s s t r i a Hubner, and the jack pine budworm, Choristoneura pinus pinus Freeman, (Pendrel 1985a; 1985b). More useful than mere detection would be to estimate a threshold catch that predicted an impending outbreak e a r l i e r than would be possible by egg or l a r v a l sampling and which allowed for more time in the planning of control operations. For example, Daterman et a_l. (1979a) estimated that a catch of 25 Douglas-fir tussock moths/trap indicated a potential outbreak in 1 or 2 years and the need for more precise follow-up sampling of egg masses and larvae. Pheromone-baited traps have been used for several years to determine the need and timing of pesticide 9 applications for control of the codling moth, Cydia pomonella (L.) (Madsen and Vakenti 1973; Riedl and Croft 1974; Vakenti and Madsen 1976) and the pink bollworm, Pectinophora qossypiella (Saunders) (Toscano et a_l. 1974). P o t e n t i a l l y damaging leve l s of the Bertha armyworm, Mamestra configurata Wlk., are also predicted by threshold catches in sex-pheromone baited traps (Turnock 1987). Allen et a l . (1986) found that a threshold catch of ten spruce budworm moths/covered funnel trap was correct 71-83% of the time in predicting a l a r v a l density of greater than one larva/branch t i p in the following generation. Trap catches could also be monitored year after year in s p e c i f i c locations that have been shown h i s t o r i c a l l y to be frequently infested, so that increasing trends in catch could be used to indicate incipient outbreaks. Shepherd et. a l . ( 1 985) recommend the use of 2 or 3 years of increasing catches of Douglas-fir tussock moths to indicate an impending outbreak and the need for egg-mass surveys. If trap catch was well correlated with the following year's l a r v a l density or host damage, then pheromone traps could possibly replace conventional sampling techniques. But t h i s i s not so simple as i t sounds because many factors influence trap catch besides population density. These include trap design and e f f i c i e n c y , trap location, pheromone blend and release rate, age of the pheromone lure, male moth a c t i v i t y as a function of weather and time of day, d i s p e r s a l , and competition from v i r g i n females (Riedl and Croft 1974; Minks 1977; Sanders 1981a; Shepherd 1979). However, s i g n i f i c a n t correlations have been 10 found between the mean catch of spruce budworm moths/plot (n = 5 traps) and the number of larvae/branch t i p in the same generation, using both sticky and high capacity traps ( r 2 , s from 0.56-0.93) (Sanders 1984b; Ramaswamy et a l . 1983). Allen et a l . (1986) obtained s i g n i f i c a n t c o r relations between trap catch of spruce budworm and l a r v a l density in the following generation ( r 2 = 0.46-0.84); correlations were improved by s t r a t i f y i n g the data by region and by omitting plots with extremely low l a r v a l populations. These results are encouraging but pheromone traps are s t i l l not used operationally in predicting l a r v a l densities of either C. fumiferana or C. o c c i d e n t a l i s . The most suitable trap design depends on the objectives of the monitoring strategy. Sticky traps may t h e o r e t i c a l l y be adequate for detecting increases in low density populations (Sanders 1978) but they begin to saturate after catches of about 50 moths/trap (Houseweart e_t a l . 1981; Sanders 1981a; Shepherd 1979). Saturation may be circumvented by bait i n g traps with very low pheromone concentrations. Sartwell et al. (1985) found s i g n i f i c a n t c o r relations ( r 2 = 0.76-0.98) between the catch of western spruce budworm males in triangular sticky traps baited with 0.0001% ALD, and the severity of d e f o l i a t i o n the subsequent year. However, sticky traps are not as suitable as high capacity traps for monitoring moth catches over a large range of l a r v a l densities (Sanders 1986a). Besides being nonsaturating, a trap should also be durable, cheap, easy to handle, sensitive enough to detect low population 11 de n s i t i e s , and consistent in trapping e f f i c i e n c y from place to place and from year to year (Sanders 1978; Carde" 1 979). There are numerous studies comparing the designs of pheromone traps (AliNiazee 1983; Beroza et a l . 1973; Bode et a l . 1973; Butt et a l . 1974; Coudriet and Henneberry 1976; Culver and Barnes 1977; Houseweart et a l . 1981; Howell 1972; Kennedy 1975; Lindgren et a l . 1984; Ramaswamy and Carde" 1982; Sanders 1978; Shepherd 1985a; Struble 1983; Tingle and M i t c h e l l 1975; T r o t t i e r et a l . 1975; Vick et a l . 1979; Wyman 1979) but few have d i r e c t l y measured trap e f f i c i e n c y ( A n g e r i l l i and McLean 1984; Elkinton and Childs 1983; Lewis and McCauley 1976; Mankin et a l . 1983; Sanders 1986a). E f f i c i e n c y can be defined in various ways and here I define two variables: (1) the percentage of moths caught that approach within 1 m of a trap; and (2) the percentage caught that land on the trap. An e f f i c i e n t trap i s obviously desirable for mass-trapping programs such as those used to suppress ambrosia beetles around sawmills and dryland sorts (Borden and McLean 1981; McLean and Borden 1979) but for population monitoring, trapping e f f i c i e n c y i s less important than low v a r i a t i o n in trap catch and consistency throughout the f l i g h t season. However, Sanders (1986a) suggested that very e f f i c i e n t traps should also have low c o e f f i c i e n t s of v a r i a t i o n . Catch in traps may also be affected by the trap's height above ground or i t s proximity to host f o l i a g e . Using sticky-board traps baited with caged v i r g i n females, M i l l e r and McDougall (1973) found that trap catch of male spruce budworm moths was much higher and less variable in traps in the mid- and 12 upper-crown leve l s than in traps near the ground. Liebhold and Volney (1984a) found that trap catch of western spruce budworm increased with trap height but only when traps were hung from trees; catches in traps suspended in mid-air were s i g n i f i c a n t l y lower than those hung in trees and did not d i f f e r between heights. Increased trap catch in proximity to host plants has also been observed in the omnivorous l e a f r o l l e r , Platynota  stultana Walsingham (AliNiazee and Stafford 1972), the gypsy moth, Lymantr ia di spar (L.) (Elkinton and Carde' 1983; Elkinton and Childs 1983), the larch casebearer, Coleophora l a r i c e l l a (Hubner)(Witzgall and Priesner 1984), the European pine shoot moth, Rhyacionia buoliana (Denis & Schiffermuller)(Daterman and McComb 1970) and the pink bollworm (Kaae and Shorey 1973). I hypothesized that: the catch of western spruce budworm male moths would be higher in traps placed in the upper canopy than in traps in the lower canopy; the catch would be higher in traps near host trees than in traps hung ^ 5 m from trees; and, that the catch would be less variable in traps hung in the open than in traps hung from trees due to reduced v a r i a b i l i t y in plume turbulence or v i s u a l stimuli near the trap. These hypotheses were tested in two simple experiments. In another series of experiments, several combinations of trap designs, pheromone concentrations, and maintenance regimes (trapping systems) were compared for their trapping e f f i c i e n c y and consistency during the f l i g h t season of budworm moths, and were tested for corr e l a t i o n with the density of larvae in the same and the following generations. For each trapping system, I 1 3 tested the hypothesis that mean catch/trap/plot would be correlated with l a r v a l density in the same- and the following-year . 1 4 MATERIALS AND METHODS RESEARCH STRATEGY The roles of the minor components in the male moth's behavior were investigated in three ways: 1) by using the EAG to measure the electrophysiological response of the male antennae to a range of concentrations of ALD, AC, and OH; 2) by observing the behavior of male moths in response to blends of ALD, AC, and OH in a wind tunnel; and 3) by comparing the numbers of moths caught in sticky traps baited with blends of ALD, AC, and OH. The population monitoring studies were done in budworm infestations near Ashcroft, B.C. over three f i e l d seasons. The ef f e c t s of various factors, such as trap design and lure age, on the mean and v a r i a b i l i t y of trap catch were evaluated. Correlations between trap catch and l a r v a l density were tested by sampling 15 plots that represented a range of population d e n s i t i e s . INSECTS Three d i f f e r e n t populations of western spruce budworm were used in the laboratory experiments: a laboratory colony; wild males from f i e l d c o l l e c t i o n s (wild); and laboratory-wild (female-male) crosses (lab-wild). Wild larvae were c o l l e c t e d as f i f t h and sixth instars from a moderate infes t a t i o n in the Oregon Jack Creek valley near Ashcroft, B.C. and were reared on current year's Douglas-fir foliage at 28 ±. 2 C, ambient 15 humidity, and 16L:8D with scotophase s t a r t i n g at 1500 h (PST). The laboratory colony was started from a st r a i n of non-diapausing western spruce budworm which had been bred for about 30 generations at the Forest Pest Management In s t i t u t e (F.P.M.I.) in Sault Ste. Marie, Ontario. The F.P.M.I. colony originated from a cross between males from the U.S.D.A. Berkeley st r a i n (generation 90) and females from a colony maintained at the P a c i f i c Northwest Forest Experimental Station in C o r v a l l i s , Oregon. Nosema sp., a microsporidian parasite which i s passed between generations via the eggs (Hsiao and Hsiao 1973), was present in the laboratory colony at low infection l e v e l s . Sweeney and McLean (1987) showed that heavy sub-lethal infections of Nosema sp. were negatively correlated with the male budworm's response to pheromone. A cross between laboratory males and wild females was made in order to introduce new genes into the colony and also to produce a s t r a i n free of Nosema sp. inf e c t i o n , which i t did successfully. Very few of the lab-wild cross larvae underwent diapause. Laboratory and lab-wild larvae were fed an a r t i f i c i a l diet (Robertson 1985) which contained Benomyl at 145 ppm to control the l e v e l of Nosema sp. and were reared following the methods outlined by Robertson (1979). Rearing conditions were: 25 ± 1 C, 30 to 45% RH and 16L:8D with the scotophase sta r t i n g at 1500 h (PST). The larvae were reared in 180 mL p l a s t i c specimen cups with about 50-100 16 larvae/cup u n t i l the 4th or 5th instar and were then transferred to p l a s t i c p e t r i dishes(15 X 100 mm) at 10-15 larvae/dish. The pupae were sexed and males to be used in behavioral tests were placed in ind i v i d u a l 180 mL p l a s t i c cups and stored at 28 i 2 C, ambient humidity, and 16L:8D with scotophase s t a r t i n g at 1500 h (PST). Adult emergence was checked d a i l y . Adults were flown in the wind tunnel between 2-6 days from eclosion. PHEROMONES The pheromones were synthesized by L.Weiler. 2 Purity was measured on a Hewlett Packard 5890A Gas Chromatograph equipped with an HP 3390A integrator and run on a s p l i t l e s s mode column (DB1701, 30 m X 1.0 u). The program was 70 C for 4.5 min, increased by 30 C/min to 250 C and remained at 250 C for 2.0 min; t o t a l run time was 12.5 min, injection temperature was 225 C, detector temperature was 275 C, and e q u i l i b r a t i o n time was 1.0 min. Each individual isomer was determined to be greater than 99% pure; the E-11-tetradecenyl acetate contained 0.2% E-11-tetradecenal and 0.2% E-11-tetradecenol. Unless otherwise sp e c i f i e d , a l l pheromone components were blended in n-heptane at the same isomer ratios found in the female e f f l u v i a , e.g_.92% E- + 8% Z- 1 1-tetradecenal, and incorporated into polyvinyl chloride (pvc) rods of 3 mm diam (Daterman 1974) at concentrations from 0.00005% to 0.5% (w:w). 2 Department of Chemistry. University of B r i t i s h Columbia. 1 7 The rods (or lures) were then cut into 5 mm lengths. Different pheromone blends were made by impaling more than one pvc rod on a pin, e.g^. a 0.05% ALD rod plus a 0.5% AC rod. Before use in the wind tunnel or in f i e l d tests, a l l pvc lures were aged 7 days in a fume hood (23-25 C) in order to s t a b i l i z e release rates ((Daterman 1982). They were stored at -10 C when not in use. I n i t i a l attempts to measure the release rate from pvc lures by weight-loss f a i l e d ; the lures often gained more weight than they l o s t , presumably through the absorption of water or the c o l l e c t i o n of dust in the fume hood. Instead, release rates of 0.05% and 0.5% ALD, 0.5% AC and 0.5% OH were estimated by capturing v o l a t i l e s on Porapak-Q and analyzing by gas-liquid chromatography (GLC). The ALD formulation was from a commercial supplier and was in a 97/3 (E/Z) isomer r a t i o ; the AC and OH lures were the same as those used in laboratory and f i e l d experiments. For each component-concentration, a 10-15 cm length of pvc was aged in the fume hood at 25 ± 1 C and ambient humidity for 7 days, and was then placed in a glass aeration chamber fed by compressed a i r (24-26 C; 20 SCFH). The compressed a i r ran through a water bath to control i t s temperature and was f i l t e r e d through activated charcoal prior to reaching the lures. V o l a t i l e s were trapped on Porapak-Q for 67 h. Two columns of Porapak-Q were connected in series in each aeration device in order to trap any v o l a t i l e s that might leak through the f i r s t column. The Porapak-Q was eluted with four 18 rinses of 5 mL ether and any rinses which contained pheromone were later combined. Trapped v o l a t i l e s were analyzed by GLC in the manner described for the determinations of pheromone purity. Tetradecane was used as the internal standard for a l l pheromone components and the r e l a t i v e weight r a t i o (RWR) of standard to pheromone was determined from the average of four standard solutions. The quantity of pheromone released from each lure was estimated using the following equation: Wt. pheromone = RWR x Wt. Standard x Area of Pheromone Area Standard where the area of pheromones and standard were provided by the GLC integrator. Release rates were then calculated per unit surface area of pvc and expressed on a per hour basis for a 5 x 3 mm lure. WIND TUNNEL The wind tunnel has a plywood flo o r and back, and a clear a c r y l i c p l a s t i c front and top. It i s 1.2 m in cross section and is described by A n g e r i l l i and McLean (1984) except for the following modifications: the length of the tunnel was reduced to 3.7 m, the baff l e s were removed from the intake end, and charcoal f i l t e r s plus a dust f i l t e r were f i t t e d to the upwind screen. Activated charcoal was held inside a g r i d consisting of 19 four p l a s t i c f i l t e r s , each measuring 61 X 56 X 2.5 cm. Air was pulled through the tunnel and expelled to the outside of the building. A guard was b u i l t around the a i r - e x i t window in order to minimize disturbance of the plume by outside winds. The windspeed in the tunnel was 40 cm/sec and the temperature was between 20 and 25 C for a l l experiments. Light intensity was 35 l x . PHEROMONE-MEDIATED BEHAVIOR Electroantennograms Antennal responses to pheromone (EAGs) were recorded using materials and methods similar to those described by Roelofs (1977). Modifications included a Faraday cage to reduce e l e c t r i c a l noise and a power supply which automatically reset the baseline signal after each EAG recording. The power supply was b u i l t by Michael Hui^ using a modified design of Perez and Rozas (1984). A stream of medical a i r (8-9 SCFH) was bubbled through a flask of water and passed continuously over the antenna. A pheromone lure was wedged cross-wise into the large end of a Pasteur pipet which was then f i t t e d onto a large syringe. Air was then puffed through the pipet and into the airstream in 5 cc quantities. Different pipets were used for each pheromone treatment. Dept. of E l e c t r i c a l Engineering, University of B r i t i s h Columbia, Vancouver, B.C. V6T 1W5. 20 Two variables were recorded from the EAG: the peak amplitude of depolarization, and the time required for the signal to return to the baseline (lag). For each EAG, a control stimulus (pvc without pheromone) was puffed three times over the antenna before and after each treatment stimulus, and the mean amplitude and lag subtracted from the means of those in response to fiv e treatment puffs. Treatments were applied in order of increasing concentration or blend complexity. Moths were tested between 2 and 7 d from eclosion. In an experiment, each antenna was exposed to a l l treatments. The r e l a t i v e response to ALD, AC, and OH was recorded from laboratory and wild moths. The responses to blends of ALD, AC and OH were recorded for lab-wild moths only. The data were analyzed by ANOVA for repeated measures (Winer 1971) on transformed data (log(x)). Laboratory and wild western spruce budworm moths were compared for amplitude and lag at each component concentration by ANOVA, or by Mann-Whitney U tests when variances were not homogeneous. Regressions were computed between the square root of amplitude and ALD concentration (log(conc x 10^)), and between the square root of lag and ALD concentration, for both wild and laboratory moths. The assumption of homogeneity of variance of the dependent variable was not met for the lag data despite many attempts at transformation (Box test P = 0.05). This did not affect the f i t of the regression l i n e but i t did af f e c t the significance test in regression analysis. Thus, the lag vs ALD concentration relationships in laboratory and wild western spruce budworm are discussed only q u a l i t a t i v e l y . The 21 regressions of amplitude vs ALD concentration were compared between wild and laboratory western spruce budworm using a slope test (Zar 1984). A precaution to note concerning these regressions i s that the assumption of independence of observations was not s t r i c t l y met because the same sample of budworm moths were used for a l l treatments. Thus, for example, the EAG responses to 0.005 % ALD were not independent of those to 0.5% ALD because the same individual budworm moths were exposed to both treatments. Wind tunnel bioassays The behavior of the laboratory, wild, and lab-wild male moths was observed in response to a range of ALD concentrations, and to various blends of 0.05% ALD, 0.5% AC, and 0.5% OH, in a series of experiments in a laboratory wind tunnel. The ef f e c t on the male moth's behavior of adding 0.05 and 0.005% of either AC, OH, or both, to 0.05% ALD was observed in the lab-wild moths only. A l l bioassays included a v i r g i n female treatment, which consisted of two v i r g i n female moths, aged 2-6 days, inside a fiberglass screen cage; and a control treatment, which consisted of a piece of pvc to which only heptane had been added. Male moths were flown from 2 h before to 3 h after the start of scotophase (1300 - 1700 h PST) in order to coincide with the male's pheromone response period (Shepherd 1979; Liebhold and Volney 1984b). The pheromone lure was stuck on a 22 pin, placed inside a small fibreglass screen cage, and the cage was suspended by a paperclip from an aluminum rod held 40 cm above the tunnel floor on a ringstand in the center of the wind tunnel. The males were acclimatized to room conditions for at least 30 min and then released i n d i v i d u a l l y from a p l a s t i c cup onto a glass platform located 40 cm above the wind tunnel floor and 2 m downwind from the lure. Each male was given 3 min in which to respond and was observed for the following behavior: wing-fanning, taking o f f , f l y i n g a stationary zig-zag in the pheromone plume (locking-on), f l y i n g a zig-zag pattern upwind towards the lure (upwind f l i g h t ) , reaching points 1 m and 1.5 m upwind from the take-off platform, touching and landing on the cage containing the pheromone, and displaying p o s t - f l i g h t pre-copulatory behavior (wing-fanning while c u r l i n g the abdomen to the side and displaying hair p e n c i l s ) . A male was considered to have landed on the cage i f i t remained there for longer than 5 s. A l l moths that f a i l e d to take off or flew to the floor were subsequently tested for their a b i l i t y to f l y in the wind tunnel. Each moth was gently launched into the a i r about 0.5 m above the wind tunnel floor and those which f a i l e d to f l y after three launches were scored as non-fliers and discarded. The i n i t i a t i o n of each behavioral variable was timed with a stop watch. Mean ground speed of upwind f l i g h t was calculated in three sections of the wind tunnel (2-1 m-, 1-0.5 m-, and 0.5 m from the lure) and was averaged over the entire wind tunnel from the points of locking-on and from the beginning of upwind f l i g h t . The following temporal variables were also calculated: 23 the i n t e r v a l s between release of the moth and the onset of wing-fanning, take-off, and landing at the lure; the inte r v a l s between taking-off and subsequently locking-on and touching the cage holding the lure; the duration of stationary zig-zag f l i g h t ( i n t e r v a l between locking-on and subsequently f l y i n g upwind or f l y i n g out of the plume); and f i n a l l y the i n t e r v a l between f i r s t touching the cage and then landing on i t . Treatment order was randomized each day, and f i v e males were flown consecutively to each treatment on each test day. For percentage response, each re p l i c a t e consisted of f i v e males; for temporal response, each responding male was considered a r e p l i c a t e . Males were flown only once per day but were sometimes used on subsequent days; t h i s was done in the bioassays comparing responses to ALD concentration in a l l three populations, and in the bioassays comparing blends of 0.05% ALD, 0.5% AC and 0.5% OH in the laboratory and wild males. S t r i c t l y speaking, the re-use of males vio l a t e d the assumption of independence in analysis of variance. These data should therefore be interpreted with f u l l knowledge that the assumptions of ANOVA are not completely met. However, e a r l i e r observations of the male moths' behavior indicated i t was not s i g n i f i c a n t l y affected by exposure to pheromone in the wind tunnel a day previous; and the d a i l y randomization of treatments and i n d i v i d u a l males made i t highly improbable that the same group of f i v e males would be flown consecutively to any given treatment. The bioassays comparing responses to blends of ALD, AC and OH in the lab-wild males used d i f f e r e n t moths each day. 24 Percent response data were transformed by arcsin( Jy~ ) and analyzed i n i t i a l l y as a randomized complete block design (blocks = days) by ANOVA and Newman-Keuls multiple range test (<* = 0.05). If the block effect was not s i g n i f i c a n t the variances were pooled and the experiment analyzed as a 1-way ANOVA. The time i n t e r v a l and ground speed data were transformed by log(y + 1) and compared between treatments within budworm populations and between populations for s p e c i f i c treatments by 1-way ANOVA and Newman-Keuls multiple range test (<*= 0.05). The mean net ground speeds in the three wind tunnel sections were compared using paired t-tests (P ^ 0.05). The variances of transformed data were homogeneous or very near to homogeneity in a l l cases (Box test; <* = 0.05)(Box 1949). F i e l d bioassays Trapping bioassays and a l l other f i e l d work, unless mentioned otherwise, took place in l i g h t to moderate budworm infestations in the Oregon Jack Creek valley, near Ashcroft, B.C. A l l blend comparisons were made using 2 L milk cartons, folded into t r i a n g l e s and coated with "Stikem S p e c i a l " 4 on the inside (Cory et a l . 1982)(sticky t r a p ) ( F i g . 2). Each trap was hung 1.5-2 m above the ground on l i v e branches and aligned with i t s long axis p a r a l l e l to the p r e v a i l i n g , evening, down-valley winds. The traps were spaced 25 m apart in a l i n e perpendicular to the p r e v a i l i n g winds (i..e. across valley) in order to Michel & Pelton Co., Emeryville, C a l i f o r n i a , U.S.A. 25 F i g . 2. Triangular sticky trap made from a 2 L milk carton and coated on the inside with "Stikem Special". 26 minimize trap and plume interference. Treatments were set up in a l a t i n square design in which treatment position was re-randomized amongst time intervals (rows=position, column=time i n t e r v a l ) . This experimental design was intended to remove the vari a t i o n in catch due to trap p o s i t i o n . A l l blend comparisons but one included a v i r g i n female treatment. The female, 2-6 d from eclosion, was inside a fibreglass mesh cage which was pinned to the inside roof of the sticky trap. An e a r l i e r study (Appendix I) showed that the v i r g i n female remained a t t r a c t i v e from 2-6 d from eclosion. The sticky traps were used because they were less expensive and more readily available than most high-capacity traps. To minimize the effects of saturation, the traps were replaced and the treatments re-randomized p r i o r to catches of 50 males whenever possible. Numbers caught were transformed by log(y + 1) and analyzed by three-way ANOVA and Newman-Keuls multiple range test (« = 0.05). The "time-replicated" l a t i n square design and the methods of trap placement and spacing described above were used in a l l f i e l d experiments, including those of monitoring studies, unless otherwise noted. 27 MONITORING WITH PHEROMONE TRAPS Factors a f f e c t i n g catches A. Age of lures As well as being sensitive enough to detect low populations of the budworm, the attr a c t i o n of the pheromone lure should remain r e l a t i v e l y constant over the duration of the budworm's f l i g h t season. The objective of these experiments was to determine the eff e c t of lure age on trap catch of western spruce budworm moths. Two concentrations of ALD, 0.05% and 0.0005%, were aged in a fume hood (24-26 C, ambient RH) for periods ranging from one to eight weeks. Once the lures were aged they were placed in glass v i a l s and stored at -10 C u n t i l used in the f i e l d bioassays. The lures were pinned inside triangular sticky traps and seven ages were compared for each concentration. Treatments were re-randomized amongst the seven positions prior to catches of 50 moths/trap whenever possible. B. Trap height and proximity to foliage In each of fi v e Douglas-fir trees, one high-capacity Uni-trap^ (Fig. 3) was hung from a l i v e branch 2 m from the ground and another in the upper canopy, about 12-15 m from the ground. The Uni-traps were baited with 0.05% ALD and contained a piece 5 International Pheromone Systems, P.O. Box 75, Broadway, Bebington, Wirral, Merseyside, England L635RQ. 28 511 F i g . 3. The high-capacity Uni-trap. 29 of Shell No Pest S t r i p ( d i c h l o r v o s ) i n the c o l l e c t i n g bucket. The traps were retrieved and the moths counted after two days. Catches in the upper and lower traps were compared using a paired t-test (P = 0.05). Covered double funnel traps, modified from a Lindgren multiple funnel trap (Lindgren 1983) by removing six of the eight funnels, were baited with "bubblecaps" which released ALD at about 50 ug/day. The bubblecap lures consisted of a p l a s t i c receptacle which contained the pheromone, covered with a p l a s t i c •7 membrane. Soapy water was added to the c o l l e c t i n g ]ars to reduce the chance of the moths escaping. Four traps were hung from tripods at least 5 m from the nearest tree (open) and another four were hung from l i v e branches of Douglas-fir ( f o l i a g e ) . Trap position (open vs foliage) was alternated across v a l l e y . The traps were re-randomized among the fixed positions three times during the nine-day trapping period. The mean catches/trap for the entire trapping period were compared between open and foliage positions using Student's t-test (P = 0.05). C. Trap design Comparisons of designs Five high-capacity trap designs were tested in two experiments in 1982 (Fig. 4). The designs 6 Shell Chemical Co. ^ The bubblecaps and the i r release rates (determined by weight loss) were provided by A. Meisen of The Department of Chemical Engineering, University of B r i t i s h Columbia. F F i g . 4. High-capacity pheromone t r a p d e s i g n s . The fu n n e l t r a p s were modified from a Lindgren funnel t r a p ( F ) ( L i n d g r e n ) . MF • M i n i - f u n n e l , HMF - H a l f - m i n i - f u n n e l , HF = H a l f - f u n n e l , K = K e n d a l l t r a p , L = l u r e . o 31 included the Kendall trap, K (Kendall et a l . 1982), the Lindgren multiple funnel trap, F (Lindgren 1983), and three modifications of the l a t t e r : with the inter-funnel distance reduced by half, HF (half-funnel); with the bottom seven funnels collapsed to simulate a double funnel trap, MF (mini-funnel); and with the bottom seven funnels collapsed and the inter-funnel distance between the bottom two funnels reduced by half, HMF (half-mini-funnel). In the f i r s t experiment the pheromone lures were suspended just above the c o l l e c t i n g jar whereas in the second experiment they were suspended between the fourth and f i f t h funnels of the funnel and half-funnel traps. The lures consisted of a crude blend of E/Z11-tetradecenal in three 1 /*1 disposable pipettes inside a 2 mL glass v i a l . Soapy water was added to the c o l l e c t i n g jar of each trap to reduce the chance of the moth's escaping. In each experiment, the traps were spaced 25 m apart and set out in a l a t i n square design (4 X 4) with rows oriented p a r a l l e l to the p r e v a i l i n g up and down-valley winds; traps were set out in the afternoon and c o l l e c t e d the following afternoon. In the f i r s t experiment, the number of moths caught between 1200 and 1430 PST was also recorded to measure the midday response of males to pheromone. E f f i c i e n c y The objectives here were to observe and compare the e f f i c i e n c y of various trap designs and to see i f efficiency-was affected by pheromone concentration. Observations were made in the f i e l d and the wind tunnel. Three types of traps were compared in the f i e l d : the sticky trap, the Uni-trap, and the 32 Multi-Pher t r a p 8 (Jobin 1985)(Fig. 5 ) . 9 The Uni-trap was tested in two va r i a t i o n s : with one piece of dichlorvos near the pheromone lure and another in the bottom of the c o l l e c t i n g bucket; and with dichlorvos in the c o l l e c t i n g bucket only. Observations of moth behavior were made near the sticky trap in 1984, and near the Uni-trap and Multi-Pher trap in 1985. The traps were observed between 18:30 and 20:30 PST. Moths f l y i n g an upwind zigzag f l i g h t towards a trap were counted when they approached within 1 m of the trap, touched or entered the trap, or were caught. Care was taken not to count a moth more than once. The sticky trap was baited with 0.05% ALD and was observed on eight d i f f e r e n t nights u n t i l a t o t a l of 80 moths had been caught. Its e f f i c i e n c y (the number caught/the number entering the trap) was calculated for each successive capture of ten moths, and for the t o t a l catch of 80 moths. The trap was rotated 180° afte r cumulative catches of 30 and 70 moths and was taken down and stored inside the equipment van between observation periods. The Uni-trap and the Multi-Pher trap were baited with 0.03% ALD, in 3 X 10 mm pvc rods, and were observed in a randomized complete block design with time periods as blocks. The traps 8 Extermination Sevigny, 2949 Chemin Ste-Foy, PQ, Canada G1X 1P3. 9 The Uni-trap and Multi-Pher traps were provided courtesy of an experiment already in progress set out by R.F. Shepherd and T.G. Gray of P a c i f i c Forestry Centre, 506 West Burnside Road, V i c t o r i a , B.C., V8Z 1M5. 33 The high-capacity Multi-Pher trap. 34 were o b s e r v e d i n random o r d e r i n e a c h t i m e p e r i o d , f o r a t o t a l o f f i v e r e p l i c a t e s / t r a p . A r e p l i c a t e c o n s i s t e d o f o b s e r v i n g a t r a p u n t i l t e n moths h a d a p p r o a c h e d w i t h i n 1 m and h a d e i t h e r l a n d e d f o r more t h a n 2 m i n , were c a u g h t , o r h a d f l o w n o u t o f s i g h t . One r e p l i c a t e / t r a p was r e c o r d e d on e a c h o f t h r e e e v e n i n g s a n d two r e p l i c a t e s / t r a p were r e c o r d e d on t h e f o u r t h e v e n i n g . The number o f moths t h a t t o u c h e d t h e t r a p o f t h o s e t h a t a p p r o a c h e d i t was r e c o r d e d , i n a d d i t i o n t o t h e two e f f i c i e n c y v a r i a b l e s d e s c r i b e d i n t h e i n t r o d u c t i o n . The d a t a were t r a n s f o r m e d ( l o g ( y + 1)) a n d t e s t e d by ANOVA a n d Newman-K e u l s m u l t i p l e r a n g e t e s t (ot = 0 . 0 5 ) . I n w i n d t u n n e l e x p e r i m e n t s , m a l e moths f r o m t h e l a b o r a t o r y c o l o n y were r e l e a s e d i n d i v i d u a l l y 2 m downwind f r o m a pheromone-b a i t e d U n i - t r a p w i t h no d i c h l o r v o s a n d t h e same v a r i a b l e s r e c o r d e d a s i n f i e l d o b s e r v a t i o n s . M o t h s were g i v e n 2 m i n t o r e s p o n d a n d were o b s e r v e d f o r 3 m i n a f t e r l a n d i n g a t t h e t r a p . F o u r c o n c e n t r a t i o n s o f ALD (0 .0005% t o 0.5%) a n d two c a g e d v i r g i n f e m a l e budworm moths were c o m p a r e d f o r t h e i r e f f e c t s on t r a p e f f i c i e n c y ; 12 m a l e s were r e l e a s e d p e r t r e a t m e n t . D e s i g n , pheromone c o n c e n t r a t i o n a n d m a i n t e n a n c e Two t r a p d e s i g n s , two pheromone c o n c e n t r a t i o n s , a n d two m a i n t e n a n c e r e g i m e s were c o m b i n e d i n a 2 X 2 X 2 f a c t o r i a l e x p e r i m e n t t o y i e l d e i g h t d i f f e r e n t t r a p p i n g s y s t e m s . The s t i c k y t r a p a n d t h e U n i - t r a p were b a i t e d w i t h 0.05% o r 0.0005% ALD. The moths were c o u n t e d e v e r y two d a y s . I n m a i n t a i n e d t r a p s , t h e moths were removed a n d t h e s t i c k y t r a p s e i t h e r c l e a n e d o r r e p l a c e d 35 e n t i r e l y . In non-maintained traps the moths were l e f t in the traps for the entire f l i g h t season to simulate operational monitoring; to avoid re-counting, moths captured in the Uni-traps were wrapped in a piece of cheesecloth. The experiment was replicated in 15 plots of varying budworm density and run for the entire f l i g h t season; eight plots were located in the Oregon Jack Creek valley and seven plots were located along the Barnes Lake road (Fig. 6). In each plot, the eight d i f f e r e n t trap systems were l a i d out in a time-replicated l a t i n square where the time period (row) varied from 2-8 d depending on the number of moths caught in the less sensitive traps. This experimental design appears unnecessarily complicated but i t was used for the following reasons: 1) to test for interactions between trap design, pheromone concentration, and maintenance regime; 2) to compare the r e l a t i v e e f f i c i e n c y and consistency of the trap systems over the entire f l i g h t season; and 3) to test and compare each trap system for c o r r e l a t i o n between catch and l a r v a l density, and the l a t i n square design allowed me to sample eight positions within each plot using only one of each trap system/plot. The data were transformed (log(y + 1)) and checked for homogeneity (Box te s t , o< = 0.05)(Box 1949). The treatment variances were homogeneous (P ^  0.05) except in plots 3, 7, and 15. However, analysis of variance was performed on the data from each plot because deviations from homogeneity do not 36 A - OREGON J A C K C R E E K B - B A R N E S L A K E ROAD F i g . 6. Map showing the location of the f i e l d studies. Eight sample plots were located in the Oregon Jack Creek valley (plots 1,3,4,11,12,13,14, and 15), and seven along Barnes Lake road (plots 2,5,6,7,8,9, and 10). A l l f i e l d bioassays comparing pheromone blends were conducted in the Oregon Jack Creek v a l l e y . 37 greatly a l t e r the p r o b a b i l i t y of making a type I error when the number of re p l i c a t e s of each treatment are equal, as they are in these experiments (Zar 1984). Mean trap catches in each plot were compared using Newman-Keuls multiple range test (ot = 0.05). The cumulative season's catches in some of the trap systems were compared using paired t-tests on transformed data (I6g(y+1)). Correlating catch with l a r v a l density A. Larval densities Larvae were sampled in the same 15 plots in which the f a c t o r i a l experiments were set up, which compared trap design, concentration, and maintenance. These plots had been selected on the basis of: 1) a wide range of l a r v a l densities between plots, as estimated from bud inspections in mid-June 1984; 2) a v a i l a b i l i t y of host trees 10-15 m t a l l with mid-crowns accessible to pole-pruners and with branches low enough to sample by branch beating; and 3) easy access from roads, because the plots were to be v i s i t e d every two days. Larval densities were estimated from mid-crown branch samples, in 9 of 15 plots in 1984 and 10 of 15 plots in 1985, and from lower branch beating in a l l 15 plots in both years. Some pupae were found during sampling but the majority by far were fourth to sixth instar larvae. Two branch t i p s , each about 45 cm long, were sampled from the mid-crown of each of 25 trees di s t r i b u t e d throughout each p l o t . The sample trees were marked and numbered so that the same trees could be sampled the 38 following year. Branch t i p s were removed using a pole-pruner with an attached nylon bag which caught the branch and reduced the chance of losing larvae. The larvae were dislodged from the cut t i p s onto a canvas ground sheet by h i t t i n g the branch several times with a yard-stick, and were counted. Each branch was then inspected for remaining budworm and also to count the number of new shoots. The length and maximum width of each branch t i p was measured and i t s foliage area was estimated as half the product of length and width (Campbell et a l . 1984). The number of larvae/100 new shoots and the number of larvae/m 2 of foliage were estimated from the combined data of the two branch samples from each tree. Lower branch samples were taken from 50 trees in each plot including the 25 trees which had been sampled by pole-pruning. Three lower branch tip s (45 cm) were sampled per tree. A beating tray, consisting of a square piece of clo t h (54 cm by 54 cm) stretched taut by a c o l l a p s i b l e metal frame, was held under a branch t i p and the branch was beaten five times with a s t i c k . Dislodged larvae were counted from a l l three branches to provide one estimate of the number of larvae/three branches for each tree. The mean number of larvae/three branches was then estimated for each plot based on 50 trees/plot. The three estimates of l a r v a l density/plot were tested for cor r e l a t i o n with each other. 39 B. Trap catches Pheromone-baited traps were set out prior to seasonal budworm f l i g h t in most plots and were not removed u n t i l the budworm f l i g h t season was completed. The t o t a l season's catch was estimated in two ways: 1) the eight trap systems described e a r l i e r in the f a c t o r i a l experiment provided eight estimates of t o t a l season's catch/plot in a l l 15 plots (based on one trap/plot); and, 2) five sticky traps and five Uni-traps, both baited with 0.05% ALD, and not maintained, were set out in completely randomized order in each of five plots (No.'s 1,2,5,7, and 12) to provide two estimates of mean t o t a l season's catch/plot. Estimates of t o t a l season's catch/plot in 1984 were then tested for c o r r e l a t i o n with estimates of l a r v a l density in 1984 and 1985. Estimates of l a r v a l density in 1985 were also tested for c orrelation with the average t o t a l season's catch in 1985 in non-maintained Uni-traps baited with 0.03% ALD. The 1985 trap catch data were provided by R.F. Shepherd of the Canadian Forestry Service at the P a c i f i c Forestry Centre in V i c t o r i a , B.C. C. Stand parameters The basal area/ha (BA), and foliage biomass/ha (FOL), were estimated in each plot and later tested as addit i o n a l independent variables in regressions of l a r v a l density vs trap catch. Two to four prism plots were made in each of the f i f t e e n 40 plots using a prism with a BAF (basal area factor) of four. Centers of the prism plots were located every 50 m along a transect running through the p l o t . The height and diameter of every tree within each prism plot was measured using a Suunto clinometer and a DBH (diameter at breast height) tape. The BA and number of stems/ha were calculated using standard formulas (Husch et a l . 1972; Watts 1983). The volume (V, in m3) of each tree included in a prism plot was estimated using an equation for i n t e r i o r Douglas-fir (Watts 1983): log V = -4.38310 + 1.74294(log D) + 1.1564l(log H) where D = dbh (cm), and H = height (m) , Oven dry foliage biomass (F, in kg) was then estimated for each sample tree using the equation for i n t e r i o r Douglas-fir developed by Standish et a l . (1985): F (kg) = -3.4 - 79.5(V) + 860.0(D 2) - 0.6(D2HV) where D = dbh (m), and t h i s was multiplied by the number of stems/ha, represented by the same tree, to give the foliage biomass/ha represented by that tree. The estimates of foliage biomass/ha for each tree were t o t a l l e d in each prism plot and these t o t a l s were averaged to give one estimate of foliage biomass/ha (FOL) for each pl o t . 41 RESULTS PHEROMONE RELEASE RATES No pheromone was detected in the second column of Porapak-Q, indicating that the f i r s t column was s u f f i c i e n t to trap the v o l a t i l e s . The fourth rinse of 5 mL ether from a l l three components, at 0.5% concentration, contained no pheromone so the f i r s t three rinses were combined for each component. Only the f i r s t two rinses of 0.05% ALD contained any pheromone and these were also combined. The release rates of 0.5% ALD, 0.5% AC and 0.5% OH, expressed per 5 X 3 mm lure, were 64.6 ng/h, 7.8 ng/h, and 32.2 ng/h respectively. This converts to a r e l a t i v e r a t i o of 10:1.2:5 (ALD:AC:OH) which i s comparable to the r a t i o of 10:3:6 found in the v i r g i n female western spruce budworm by S i l k et. a l . (1982), and to the r a t i o of 10:5:7.5 found in pvc lures by Daterman et a l . (1979b), except that the r e l a t i v e release rates of the minor components were lower. Alford et al.(1983) suggested that the release rate of AC from pvc would be 2-3 times the release rate of ALD. The release rate of 0.05% ALD/5 X 3 mm lure was 4.4 ng/h as compared with 1.5 ng/h (Silk et a l . 1982) and 2-5 ng/h (Cory et a l . 1982) from v i r g i n female C. occidentalis, and with 4 ng/h (Morse et a l . 1982) and 10.6 ng/h (Ramaswamy and Carde 1984) from v i r g i n female C. fumiferana. It also compares with ALD release rates of 8 ng/h from 0.01% ( 5 X 3 mm) pvc lures (Cory et 42 a l . 1982) and 4-40 ng/h (aged 15-50 days) from 0.03% (10 X 4 mm) pvc lures (Sanders 1981b). Because i t s release rate approximated that of a v i r g i n female, the 0.05% ALD lure was used in blend tests which assayed the effect of adding minor components. The analyses of v o l a t i l e s indicated that in addition to releasing 7.8 ng/h of AC, the 0.5% AC lure was releasing contaminants of ALD and OH at respective rates of 2.0 ng/h and 10.1 ng/h. This was surprising because the o r i g i n a l E-11-tetradecenyl acetate contained only 0.2% of the aldehyde and 0.2% of the alcohol. Also, the 0.5% ALD lure was estimated to be releasing 20.7 ng/h of OH in addition to 64.6 ng/h ALD. It is possible that the pheromones deteriorated or reacted with chemicals in the pvc. Unfortunately, the actual breakdown and contamination of the ALD lures i s unknown because the release rates were determined using a 97/3 (E/Z)-11-tetradecenal formulation purchased from a commercial supplier (Orsynex), instead of the formulation used in the wind tunnel and f i e l d experiments. However, the commercial formulation was assumed to represent the release rate and possible deterioration of the o r i g i n a l ALD formulation adequately, because both formulations were o r i g i n a l l y greater than 99% pure according to the GLC analysis. The evidence of contamination makes i t d i f f i c u l t to interpret the roles of the minor components in the male moth's behavior. The effects of either AC, ALD, or the ALD+AC blend, 43 cannot be determined precisely because of the OH contamination apparent in both lures. However, by taking the contamination into account and by making some assumptions, I used the release rate data to make up a lure combination that approximated that released from a v i r g i n female. The 0.05% ALD lure released pheromone at about 6.7% the rate of 0.5% ALD. I assumed a similar r e l a t i o n s h i p for AC and OH and calculated that 0.05% AC and 0.05% OH would release about 0.53 ng/h and 2.17 ng/h respectively. I also assumed that release rates were uniform per unit surface area of pvc and calculated that a 10:3:6 r a t i o of ALD:AC:OH would be approximated by a combination of 0.05% ALD ( 5 x 3 mm) plus two 0.05% AC lures, each measuring 6.5 X 3 mm. This combination was tested in the wind tunnel with the lab-wild males. PHEROMONE-MEDIATED BEHAVIOR Electroantennograms Mean amplitude of antennal response increased with greater concentrations of ALD (Fig. 7A and B). The simple linear regressions of amplitude vs ALD concentration (log(X x 10^)) were s i g n i f i c a n t for both laboratory ( r 2 = 0.77)(Fig. 8A) and wild western spruce budworm ( r 2 = 0.73) (Fig. 8B). The two regressions were not s i g n i f i c a n t l y d i f f e r e n t (test for slope and elevation ; P = 0.05, Zar 1984). Lag also increased with greater concentrations of ALD in both laboratory and wild males but the mean lag at each concentration from 0.005-0.5% was greater in the laboratory males (Fig. 9A) than in the wild males 4 4 0.00005 0.0005 0.005 0.05 0.5 2 - i 0.00005 0.0005 0.005 0.05 0.5 CONCENTRATION (X In DVC) IZZ1 ALD AC VZZL\ OH Fig. 7. Mean peak amplitude (± S.E.) of western spruce budworm adult male EAG response to a range of concentrations of ALD, AC, and OH. A. Laboratory males (n = 19). B. Wild males (n = 20). Each male was tested with a l l components and concentrations. 45 > E III a a. > E \* u Q Q. 1.8 -1.6 -a. WILD 0.5 1.9 § • • • • -I— 2.5 i 3.5 4.5 CONCENTRATION OF AID (Log x ( 1 0 d ) F i g . 8. Regressions of peak amplitude of EAG response ( Sy) of western spruce budworm a d u l t males y_s ALD c o n c e n t r a t i o n (Log x ( 1 0 5 ) ) . A. Laboratory males (n = 19 / c o n c e n t r a t i o n ) . B. W i l d males (n = 2 0 / c o n c e n t r a t i o n ) . The r e g r e s s i o n s are each s i g n i f i c a n t ( P ^ 0.001) but are not s i g n i f i c a n t l y d i f f e r e n t from each other (P ^  0.05). 46 3 0.00005 0.0005 0.005 8 -7 -6 -5 -4 3 2 -1 -B. WILD —I 0.00005 T (A T 0.05 I 0.05 0.0005 0.005 CONCENTRATION (X In mc\ rzzi ALD rxs AC &Z2 OH i 0.5 F i g . 9 . Mean lag (±S.E.) following response (EAG) of western spruce budworm adult males to a range of concentrations of ALD, AC, and OH. A. Laboratory males (n 1 9 ) . B. Wild males (n = 2 0 ) . Each male was tested to a l l components and concentrations. 47 (Mann Whitney U test; P = 0.05) (Fig. 9B). The regressions of lag vs ALD concentration (log(X x 10^)) were c u r v i l i n e a r for both laboratory and wild males (Fig. 10A and B). Both laboratory and wild western spruce budworm responded to AC and OH but only at concentrations ^ 0.005% and with smaller amplitude and lag r e l a t i v e to ALD (Figs. 7,9). At each concentration > 0.005% , mean amplitude and lag were s i g n i f i c a n t l y greater in response to ALD than in response to AC or OH (ANOVA, Newman-Keuls multiple range test; P = 0.05%). At 0.05%, mean amplitude i s greater in response to AC than to OH in both laboratory and wild western spruce budworm. The percentage of males responding with ^.0.1 mv amplitude increased with increasing concentration of each component (Fig. 11A and B). A s i g n i f i c a n t l y larger proportion of wild western spruce budworm responded to 0.05% AC than did laboratory western spruce budworm ( 2 X 2 chi square test; P = 0.05). The mean amplitude of wild males in response to 0.05% AC was s i g n i f i c a n t l y greater than that found in the lab males (Mann Whitney U test; P = 0.02). Binary and ternary blends of 0.05% ALD, 0.5% AC and 0.5% OH did not e l i c i t s i g n i f i c a n t l y d i f f e r e n t amplitude or lag than did 0.05% ALD by i t s e l f (Fig. 12A and B). 48 4.5 4 -3.5 -3 2.5 -B. WILD y - -1.14x + 0.65x2 - 0.07x3 + 0.62 r 2 - 0.81 B CONCENTRATION OF ALD (Log x (10 ) F i g . 10. Regressions of lag (>/y~) vs ALD concentration (Log x (10^)) following antennal response (EAG) of western spruce budworm adult males. A. Laboratory males (n = 19/concentration). B. Wild males (n = 20/concentration). The regressions are each s i g n i f i c a n t (P^- 0.001). 4 9 (9 Z 5 z o 0. 13 o u 8 o Q. 100 80 -60 -40 -20 -A. LAB 2 CA 0.00005 T 0.0005 1 1 i 0.005 23 0.05 0.5 a z o a. 13 o u o 100 -80 -60 -40 -20 -B. WILD 7~ CA CA 7, T I 0.00005 0.0005 0.005 0.05 COMPONENT CONCENTRATION {% In^pyc) 1771 ALD AC £22 OH 0.5 F i g . 11. Percentage of western spruce budworm adult male antennae responding to a range of concentrations of ALD, AC and OH on the EAG. A. Laboratory males (n = 19). B. Wild males (n = 20). Each male was tested to a l l components and concentrations. 5 0 u Q 0. 1 AID r * * — r ALO/AC ALO/OH ALO/AC/OH r AC OH i a ALD/AC ALO/OH ALD/AC/OH PHEROMONE BLEND F i g . 12. Mean EAG response of western spruce budworm male antennae ( l a b - w i l d ; n = 19) to blends of 0.05% ALD, 0.5% AC, and 0.5% OH. A. = amplitude vs blend. B. = l a g vs ble n d . Each antennae was exposed t o a l l treatments; d i f f e r e n t l e t t e r s i n d i c a t e s i g n i f i c a n t d i f f e r e n c e s (ANOVA f o r repeated measures and Newman-Keuls,c* = 0.05). 51 Wind tunnel bioassays A. Response vs ALD concentration Percentage response The v i r g i n female stimulated the greatest percentage response in a l l behavioral variables except wing-fanning in a l l three populations, take-off in wild moths, and reaching the lure in lab-wild moths. Percentage response to the v i r g i n female was s i g n i f i c a n t l y greater than that to 0.05% ALD in only a few cases, e.c[. locking-on, upwind f l i g h t , reaching 1 m, and copulatory attempts in the wild moths; and copulatory attempts in the lab-wild moths. The results s t i l l suggest, however, that the males were responding to something more than simply the ALD (Tables 1-3). The mean threshold concentration for upwind, zig-zag f l i g h t towards the lure appeared to l i e between 0.0005% and 0.005% ALD. However, t h i s depends on how one defines "threshold". A small proportion of males (6-10%) flew upwind to reach the 0.00005% ALD lur e . Obviously, the threshold concentration varied with individual moths. The percentage of males taking o f f , f l y i n g a zig-zag f l i g h t upwind and landing at the lure dropped off above and below 0.05% ALD whereas percentage wing-fanning reached a peak in response to 0.5% ALD. There are no s i g n i f i c a n t differences in percentage response for most behaviors between 0.005 and 0.5% ALD in a l l three populations (Tables 1-3). When the data from a l l three populations were combined and analyzed in one large one-way ANOVA a few differences were noted Table 1. Response of western spruce budworm male moths (laboratory) to a range concentrations of ALD, compared with response to two v i r g i n females. A l l concentrations were formulated 1n 5 X 3 mm rods. TREATMENT MEAN PERCENT BEHAVIORAL RESPONSE (n = 8) 1 , 2 3,4 W1ng Take Lock Upwind 1m 1.5m Touch Land Cop/n Cop/ fan o f f on f l i g h t land FEMALE 69 a 89 a 59 a 54 a 52 a 47 a 47 a 44 a 21 44 0.5 % 93 a 80 ab 38 ab 25 ab 20 be 20 ab 20 abc 20 abc 10 33 0.05 % 80 a 85 a 55 a 48 a 35 ab 33 ab 33 ab 33 ab 13 31 0.005 % 70 a 73 ab 33 ab 30 ab 28 abc 28 ab 25 abc 25 abc 13 56 0.0005 % 18 b 48 b 10 be 10 b 10 be 8 ab 5 be 5 be 3 50 0.00005 % 8 b 48 b 10 be 10 b 10 be 10 ab 10 be 10 be 0 0 CONTROL 3 b 15 c 0 c 0 b 0 c 0 b 0 c 0 c 0 Means followed by same l e t t e r ( s ) are not s i g n i f i c a n t l y d i f f e r e n t 1-way ANOVA & Newman-Keuls « = 0.05 on transformed data ( a r c s i n / y " ). n = number of r e p l i c a t e s of 5 males each; i e . when n=8, 40 males were flown per treatment. Cop = copulatory behavior. S i g n i f i c a n t treatment e f f e c t (ANOVA «• = 0.05) but means not separable by Newman-Keuls. Table 2. The response of western spruce budworm male moths (wild) to a range of concentrations of ALD, compared with response to two v i r g i n females. A l l concentrations were formulated 1n 5 X 3 mm pvc rods. TREATMENT MEAN PERCENT BEHAVIORAL RESPONSE (n = 7 ) 1 . 2 Wing Take Lock Upwind 1m 1.5m Touch Land Cop/n Cop/ fan off on f l i g h t land FEMALE 51 a 85 G5 a 56 a 47 a 41 a 39 a 39 a 13 a 33 0.5 % 51 a 83 46 ab 29 b 17 be 14 ab 14 ab 14 ab 0 b 0 0.05 % 20 b 89 34 b 26 b 23 be 23 ab 23 ab 23 ab 0 b 0 0.005 % 6 b 80 31 b 29 b 26 ab 23 ab 23 ab 23 ab 0 b 0 0.0005 % 6 b 4G 3 c 3 c 3 c 3 b 3 b 3 b 0 b 0 0.00005 % 3 b G9 11 c 9 be 6 be 6 b 6 b 6 b 3 b 50 CONTROL 0 b 57 2 c 2 c 2 c 2 b 2 b 2 b 0 b 0 1 Means followed by same l e t t e r ( s ) are not s i g n i f i c a n t l y d i f f e r e n t 1-way ANOVA & Newman-Keuls <* = 0.05 on transformed data ( a r c s i n / y ~ ) . n = number of r e p l i c a t e s of 5 males each; l e . when n=7, 35 males were flown per treatment. Cop = copulatory behavior. S i g n i f i c a n t treatment e f f e c t (ANOVA oc = 0.05) but means not separable by Newman-Keuls. Table 3 The response of western spruce budworm male moths ( l a b - w i l d ) to a range of c o n c e n t r a t i o n s of ALD, compared w i t h response to two v i r g i n females. A l l c o n c e n t r a t i o n s were formulated i n 5 X 3 mm pvc rods. TREATMENT MEAN PERCENT BEHAVIORAL RESPONSE (n = 8) 3 W1ng Take Lock Upwind 1 m 1.5m Touch Land Cop/n Cop/ f a n o f f on f l i g h t land FEMALE 39 be 88 a 70 a 63 a 60 a 58 a 51 a 46 a 24 a 43 a 0.5 % 68 a 78 ab 58 ab 38 ab 38 a 33 ab 33 ab 30 ab 8 b 40 ab 0.05 % 58 ab 83 ab 68 a 63 a 60 a 53 a 53 a 53 a 3 b 5 b 0.005 % 20 cd 63 ab 38 b 33 b 33 a 33 ab 30 ab 30 ab 3 b 7 b 0.0005 % 8 de 65 ab 15 c 15 be 10 b 10 be 8 be 8 be 3 b 33 b 0.00005 % 3 de 48 be 10 c 10 c 10 b 10 be 10 be 10 be 0 b 0 b CONTROL 0 e 30 c 0 c 0 d 0 b 0 c 0 c 0 c 0 b Means f o l l o w e d by same l e t t e r ( s ) are not s i g n i f i c a n t l y d i f f e r e n t 1-way ANOVA & Newman-Keuls e* = 0.05 on transformed data ( a r c s i n / y " ) . n = number of r e p l i c a t e s of 5 males each; i e . when n = 8, 40 males were flown per treatment. 'Cop = c o p u l a t o r y behavior. U l 55 between populations. The laboratory colony displayed s i g n i f i c a n t l y more wing-fanning and copulatory attempts than did the wild population, especially at lower concentrations of ALD. In the presence of a blank pvc con t r o l , a large percentage of wild males (57%) took off and flew to the c e i l i n g of the wind tunnel (Table 2). In contrast, only 15% of the laboratory males took off to the control stimulus; the rest remained motionless on the platform (Table 1). An intermediate percentage (30%) of lab-wild males took off in the presence of the control stimulus (Table 3). There was much v a r i a b i l i t y in the data. Some males f a i l e d to respond to 0.05% ALD whereas the occassional one responded to 0.00005% ALD. The standard deviations of mean percent response were not included in the tables in order to save space, but i t is apparent from the lack of s i g n i f i c a n t differences in the means tests that the variances were quite large. The c o e f f i c i e n t s of variation of percentage response, averaged for the three populations, show that v a r i a t i o n was lowest in response to v i r g i n females and increased at concentrations above and below 0.05% ALD (Table 33, Appendix I I ) . Despite the large v a r i a b i l i t y in response there appeared to be a po s i t i v e r e l a t i o n s h i p between ALD concentration up to 0.05% and percentage response of a l l behaviors except p o s t - f l i g h t copulatory attempts in a l l three populations. 56 Temporal response As ALD concentration decreased, the time in t e r v a l between release of a moth in the wind tunnel and the onset of wing-fanning increased s i g n i f i c a n t l y in the laboratory males. Time to take-off was s i g n i f i c a n t l y delayed at low concentrations in a l l three populations (Tables 4-6). The duration of stationary zig-zag f l i g h t of wild and lab-wild males was s i g n i f i c a n t l y longer in response to 0.5% ALD than to the v i r g i n female, suggesting that excessive ALD concentration may i n h i b i t upwind f l i g h t (Tables 5,6). The time i n t e r v a l from i n i t i a l release, or from take-off, to landing at the lure appeared to be not related to ALD concentration but was shortest in response to the v i r g i n female. Males from the laboratory, wild and lab-wild populations did not d i f f e r s i g n i f i c a n t l y in any temporal variable in response to 0.5% ALD (ANOVA, c* = 0.05) but there were a few differences in response to the other treatments (Tables 4-9). In response to the v i r g i n female, the mean time from release on the platform to landing at the lure was s i g n i f i c a n t l y longer (62 s) in the laboratory males than in the wild (36 s) and lab-wild males (35 s)(Tables 4,5 and 6 respectively). In response to 0.005% ALD, the mean time from take-off to lock-on was s i g n i f i c a n t l y longer in the lab-wild males (8.3 s) than in wild (2.9 s) or laboratory males (2.2 s ) . Net upwind ground speed in response to 0.05% ALD was s i g n i f i c a n t l y slower in laboratory males (Table 7) than in wild (Table 8) or lab-wild males (Table 9), at 2-1 m and 1-0.5 m from the lure, and averaged over the Table 4. The temporal responses of western spruce budworm adult males ( laboratory) to a range of of concentrat ions ALD in a wind tunnel . Responses were compared with those to a v i r g i n female and a blank c o n t r o l . Due to the low number of responders, data from the CONTROL, and ALD concentrat ions less than 0.0005% were not included in the ANOVA or means t e s t s , except for the v a r i a b l e of R-TO. A l l concentrat ions were formulated In 5 X 3 mm pvc rods. TREATMENT MEAN TIME INTERVAL (s) n R-WF n R-TO n TO-LO n STAT ZZ n T--L n R--L n TO--L FEMALE 26 7.5 b 34 28.3 be 22 13.5 21 4 .6 16 7 .8 16 62 .3 16 37 .O 0 .5 % ALD 37 6.7 b 30 24.0 abc 15 7.7 12 5 8 8 2 .0 8 72 .3 8 62 .9 0.05 % ALD 30 6.2 b 34 24.4 c 22 4.5 22 9 .9 13 1 .8 13 69 .4 13 52 .9 0.005 % ALD 28 27.8 a 29 37.7 ab 13 2.2 13 5 .8 10 2 .6 10 75 .8 10 36 .7 0.0005 % ALD 8 41.9 a 19 46.5 ab 4 7.8 4 8 .5 2 8 .0 2 117 .5 2 30 .5 0.00005 % ALD 3 38.3 19 52.2 a 4 3.3 4 1 . .5 4 3 .0 4 104 .8 4 22 . 3 CONTROL 1 7.0 7 59.6 abc Means with in columns fol lowed by d i f f e r e n t l e t te r ( s ) are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, ot = 0 . 0 5 . R * Release on p lat form; WF >» I n i t i a t i o n of wlng-fannlng; TO » Take o f f ; LO • Lock-on ( I n i t i a t i o n of z l g - z f l i g h t ) ; STAT.ZZ » Duration of s tat ionary z ig - zag f l i g h t ; T • Touching lure cage; L » landing at lure cage Table 5. The temporal responses of western spruce budworm adult males (wild) to a range of concentrat ions of ALD in a wind tunnel . Responses were compared with those to a v i r g i n female and a blank c o n t r o l . Due to the low number of responders, data from the CONTROL and ALD concentrat ions less than 0.005% were not included In the ANOVA or means t e s t s , except for the va r iab le of R-TO. A l l concentrat ions were formulated in 5 X 3 mm pvc rods. TREATMENT 1 3 MEAN TIME INTERVAL (s) ' n R-WF n R-TO n TO-LO n STAT.ZZ n T-L n R-L n TO-L FEMALE 15 10. .7 30 12 .9 21 3 .3 21 2 .7 b 13 4 .7 13 36 .2 12 24 .9 0 . 5 % ALD 17 4, . 1 29 31 .2 15 4 . 1 12 11 .  1 a 4 2 .5 5 76 0 5 55 .2 0 .05 % ALD 6 10 . 1 31 18 .9 11 5 .0 10 2 .8 b 9 4 .6 9 47 . 8 9 34 .3 0.005 % ALD 2 31 . 0 28 31 .8 11 2 .9 11 3. .5 b 9 0 . 1 8 74 . 4 8 28 . 1 0.0005 % ALD 2 16 0 17 28 .2 0.00005 % ALD 1 15. 0 25 21 . 1 2 1 . .5 2 2. .5 1 0 .0 1 30. .0 1 28 .0 CONTROL 18 30.9 Means within columns fol lowed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls at. • 0 .05 . S i g n i f i c a n t treatment e f f e c t (ANOVA « » 0.05) but means not separable by Newman-Keuls. R » Release on p la t form; WF » I n i t i a t i o n of wing-fanning; TO » Take o f f ; LO • Lock-on ( I n i t i a t i o n of z l g - z f l i g h t ) ; STAT.ZZ « Duration of s tat ionary z ig - zag f l i g h t ; T » Touching lure cage; L = landing at lure cage Table 6. The temporal response of western spruce budworm adult mates ( l a b - w i l d ) in response to a range of concentrat ions ALD In a wind tunnel . Responses were compared with those to a v i r g i n female and a blank c o n t r o l . Due to the low number of responders, data from the CONTROL, and ALD concentrat ions less than 0.005% were not Included 1n the ANOVA or means t e s t s , except for the v a r i a b l e of R-TO. A l l concentrat ions were formulated In 5 X 3 mm pvc rods. TREATMENT MEAN TIME INTERVAL (s) 1,2 n R-WF n R-TO n TO-LO n STAT. ZZ n T--L n R -L n TO -L FEMALE 16 5.9 33 16.4 b 25 3.9 23 3. 8 b 17 6 .4 17 34 .9 17 25 .6 0 .5 % ALD 26 9.2 29 25.2 ab 23 5.9 21 8. 0 a 12 2 . 1 12 61 .9 12 46 .4 0.05 % ALD 22 11.4 33 20.8 b 26 5.4 26 6. 6 ab 21 4 .0 21 53 .6 21 35 .8 0.0O5 % ALD 6 22.2 26 26.5 ab 16 8.3 16 2. 0 ab 14 1 .6 14 47 .6 14 38 . 1 0.0005 % ALD 3 30.0 26 21.3 ab 6 6.3 6 0. .8 3 0 .0 3 47 .O 3 27 .3 0.00005 % ALD 1 47.0 19 38.3 a 4 3.3 4 0. 5 4 1 .3 4 71 .8 4 34 .8 CONTROL 10 39.8 ab Means wi th in columns fol lowed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, «* » 0 . 0 5 . R » Release on p lat form; WF = I n i t i a t i o n of wing-fanning; TO = Take o f f ; LO = Lock-on ( I n i t i a t i o n of z i g - z a g f l i g h t ) ; STAT.ZZ » Duration of s tat ionary z ig - zag f l i g h t : T = Touching lure cage; L « landing at lure cage. Table 7. The net ground speed of f l i g h t of adult male western spruce budworms (laboratory) 1n response to a range of concentrations of ALD In a wind tunnel. Speed was measured 1n three sections of the tunnel and averaged from the s t a r t of stat i o n a r y zig-zag (LO-T) and the s t a r t of upwind f1ight(UF-T). Due to the low number of responders, data from ALD concentrations less than 0.005% were not used 1n the ANOVA or means t e s t s . A l l concentrations were formulated in 5 X 3 mm pvc rods. TREATMENT MEAN NET GROUND SPEED OF FLIGHT (cm/s) n 2m- 1m 2 n 1m-0. . 5m n 0. , 5m -T n UF -T n LO -T FEMALE 18 17 .8 ab 17 15 . 4 a 17 12 .8 17 13 .5 17 12 . 2 0.5 % ALD 9 7 .3 b 8 8 . 1 ab 8 8 .3 8 7 . 3 8 6 .8 0.05 % ALD 18 1 1 .8 b 14 5. .7 b 13 6 .9 13 7 .7 13 7 . 1 0.005 % ALD 10 19 .6 a 10 13. .5 a 10 7 .8 10 12 .0 10 9 .8 0.0005 % ALD 4 23 . 3 3 9. .0 1 1 .3 2 6 . 2 2 5 . 5 0.00005 % ALD 3 32 .5 4 17. , 1 4 8 .7 4 14 .5 4 14 .0 Means within columns followed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls ( «* = 0.05). Distance from the pheromone source. T a b l e 8. The net gr o u n d speed o f f l i g h t o f a d u l t male w e s t e r n s p r u c e budworm ( w i l d ) i n r e s p o n s e t o a range o f c o n c e n t r a t i o n s o f ALD i n a wind t u n n e l . Speed was measured i n t h r e e s e c t i o n s of t h e t u n n e l and a v e r a g e d from t h e s t a r t o f s t a t i o n a r y z i g - z a g (LO-T) and t h e s t a r t of. upwind -f 1 i g h t ' (UF-T) . Due t o t h e low number o f r e s p o n d e r s , d a t a from ALD c o n c e n t r a t i o n s l e s s t h a n 0.005% were not used i n t h e ANOVA o r means t e s t s . A l l c o n c e n t r a t i o n s were f o r m u l a t e d i n 5 X 3 mm pvc r o d s . TREATMENT MEAN NET GROUND SPEED OF FLIGHT (cm/s) n 2m-1m2 n 1m-0.5m n 0. 5m -T n UF-T n LO-T FEMALE 18 22 . 1 14 21.5 a 14 9 . 3 14 15.0 13 1 4 . 4 a 0.5 % ALD 8 10. 1 5 7.9 b 4 5 .4 5 9.0 5 7.4 b 0.05 % ALD 8 27 . 3 9 20.1 ab 7 6 . 7 9 13.4 8 9 . 5 ab 0.005 % ALD 9 18.0 8 17.2 ab 8 6 . 1 8 10.9 8 8.3 b 0.0005 % ALD 0.00005 % ALD 1 20.0 1 5.0 1 Means w i t h i n columns f o l l o w e d by d i f f e r e n t l e t t e r ( s ) a r e s i g n i f i c a n t l y d i f f e r e n t ANOVA and Newman-Keuls ( <* = 0.05). D i s t a n c e from t h e pheromone s o u r c e . Table 9. The net ground speed of f l i g h t of adult male western spruce budworms (lab-wild) in response to a range of concentrations of ALD in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the s t a r t of stationary zig-zag (LO-T) and the s t a r t of upwind f l i g h t (UF-T). Due to the low number of responders, data from ALD concentrations less than 0 . 0 0 5 % were not used in the ANOVA or means t e s t s . A l l concentrations were formulated in 5 X 3 mm pvc rods. TREATMENT MEAN NET GROUND SPEED OF FLIGHT (cm/s) 1 n 2m- 1m 2 n 1m-0. . 5m n 0.5m-T n UF -T n LO -T FEMALE 21 31 .0 a 21 18 . 6 19 11.7 18 16 .9 18 15 .9 a 0.5 % ALD 15 21 . 1 b 13 12. . 1 13 7. 1 13 10 .4 13 9 .2 b 0.05 % ALD 24 21 .2 ab 22 1 1 . ,4 20 6.5 21 1 1 .0 21 10 .2 ab 0.005 % ALD 15 27 .9 ab 15 10. , 3 14 8 . 3 14 10 .6 14 9 .9 ab 0.0005 % ALD 4 17 .0 4 16. .7 4 3.5 3 9 .3 3 9 .0 0.00005 % ALD 4 12 .0 4 9 . 5 4 4 . 5 4 6 .9 4 6 .9 Means within columns followed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls, ( <* = 0.05). Distance from the pheromone source. 63 entire f l i g h t from the onset of upwind f l i g h t u n t i l touching the lure. Preliminary tests using from 10 to 10^ ng of ALD dropped onto f i l t e r paper disks indicated that the male moth's net upwind ground speed decreased as the pheromone concentration increased (Table 10). Using pvc lures, there was an inverse trend in upwind ground speed associated with ALD concentration in the laboratory males at 2-1 m from the lure . Net upwind ground speed was s i g n i f i c a n t l y higher in response to 0.005% ALD than to 0.5% ALD (Table 7). This trend was less evident in the laboratory males at distances near the lure and was absent in the wild and lab-wild males at a l l distances (Tables 8, 9). Mean ground speed, averaged from the onset of locking-on u n t i l touching the lure (LO-T), was s i g n i f i c a n t l y greater in response to the v i r g i n female than to 0.5% ALD, in the wild and lab-wild males but not in the laboratory males. Ground speed of laboratory males at 1-0.5 m from the lure was s i g n i f i c a n t l y greater in response to the v i r g i n female (15.4 cm/s) than to 0.05% ALD (5.7 cm/s); a similar trend was observed in the wild and lab-wild males but the differences were not s i g n i f i c a n t . The mean ground speed usually decreased as the budworm approached within 30-40 cm of the lure . In a l l three populations, the net ground speed from 0.5 m to the lure was s i g n i f i c a n t l y lower than that 1-0.5 m from the lure, which in turn was s i g n i f i c a n t l y lower than that 2-1 m from the lure (paired t - t e s t s , treatments within populations combined, P 64 T a b l e 10. P r e l i m i n a r y o b s e r v a t i o n s showing the e f f e c t of ALD c o n c e n t r a t i o n on net upwind ground speed of f l y i n g w e stern spruce budworm male moths i n a wind t u n n e l . Pheromone was d i l u t e d i n n-heptane and added i n s p e c i f i c amounts t o a 2 cm 2 d i s c of f i l t e r p aper. C o n c e n t r a t i o n n 1 F l i g h t speed (cm/s)  of ALD 3 m t o 0.5m 0.5 m t o t o u c h i n g (ng) from l u r e the l u r e 10 2 29 4 1 0 2 6 24 4 1 0 3 1 0 1 5 4 1 0 4 6 10 5 10 5 6 7 4 n = number o f male moths which l ocked -on and f l e w upwind. 65 0.05). The angles of the zig-zag f l i g h t appeared to increase r e l a t i v e to the wind l i n e when the moth was 10-20 cm from the lure (Fig. 13). B. The roles of minor components Percentage response By themselves, neither 0.5% OH nor 0.5% AC were s i g n i f i c a n t l y a t t r a c t i v e to males from any of the three populations (Tables 11-13). The 0.5% AC lure was expected to a t t r a c t some males because, according to the GLC analysis of trapped v o l a t i l e s , i t was releasing ALD at almost half the rate of that from a 0.05% ALD lure. The fact that response to 0.5% AC (actually a ternary blend of ALD:AC:OH at r e l a t i v e release rates of 2:8:10) was rare and not s i g n i f i c a n t l y d i f f e r e n t from a blank pvc control suggests that the blend of components i s as important as the release rate in stimulating normal behavioral response. The addition of 0.5% AC to 0.05% ALD increased percentage upwind f l i g h t of wild males (Table 12) but had no s i g n i f i c a n t e f f e c t on percentage response in laboratory or lab-wild males (Tables 11, 13). Again i t should be noted that according to the GLC analysis of trapped v o l a t i l e s , the combined lure of 0.05% ALD and 0.5% AC actually represented a ternary blend of ALD:AC:OH at a r a t i o of about 6:8:10. Adding 0.5% OH to 0.05% ALD decreased the response of males from a l l three populations but the ef f e c t was most pronounced in ^ r • a ? l u r e . 1 •*— 10 cm - — -F i g . 13. Typical zig-zag upwind f l i g h t path of a male western spruce budworm moth in response to pheromone (0.05% ALD) in the wind tunnel. The f l i g h t was videotaped, played back frame by frame, and the f l i g h t path traced on a piece of acetate placed over the te l e v i s i o n monitor. Each "x" represents a 1 s i n t e r v a l . Windspeed = 0.40 cm/s. Note the much f l a t t e r zig-zags within 10-20 cm of the lure. Table 11. The e f f e c t on the response of western spruce budworm male moths (laboratory) In a wind tunnel, of adding 0.5% AC, 0.5% OH, or both, to 0.05% ALD. A l l components were formulated in 5 X 3 mm pvc rods. TREATMENT MEAN PERCENTAGE BEHAVIORAL RESPONSE (n = 7) Wing Take Lock Upwind 1m 1.5m Touch Land Cop./n Cop./ fan o f f on f l i g h t tt land FEMALE 57 a 74 a 49 a 46 a 43 a 40 a 40 a 40 a 17 ab 43 ALD+AC+OH 60 a 69 a 43 a 43 a 40 a 40 a 40 a 40 a 17 ab 43 ALD+AC 69 a 80 a 60 a 57 a 54 a 54 a 54 a 54 a 14 ab 26 ALD+OH 54 a 66 a 49 a 37 a 34 a 31 a 31 a 31 a 17 ab 55 ALD 51 a 83 a 57 a 49 a 49 a 46 a 46 a 46 a 26 a 57 AC 6 b 31 b 3 b 3 b 3 b 3 b 3 b 3 b 3 b 100 OH 3 b 31 b 3 b 3 b 3 b 3 b 3 b 3 b 3 b 100 CONTROL 0 b 3 c 0 b 0 b 0 b 0 b 0 b 0 b 0 b Means within columns followed by same l e t t e r ( s ) are not s i g n i f i c a n t l y d i f f e r e n t , 1-way ANOVA & Newman-Keuls, ot = 0.05 on transformed data ( a r c s i n /y" ). n = number of r e p l i c a t e s of 5 males each; ie. when n = 7, 35 males were flown. Cop. = copulatory behavior. GLC a n a l y s i s of v o l a t l l e s c o l l e c t e d from pvc indicated that the ALD contained some OH and the AC lure contained both ALD and OH contaminants. Table 12. The e f f e c t on the response of western spruce budworm male moths ( w i l d ) i n a wind t u n n e l , of adding 0.5% AC, 0.5% OH, or both, to 0.05% ALD. A l l components were formulated i n 5 X 3 mm pvc rods. TREATMENT 4 MEAN PERCENTAGE BEHAVIORAL RESPONSE (n = 7) W1ng Take Lock Upwind 1m 1.5 m Touch Land Cop./n Cop./ fan o f f on f l i g h t ff land FEMALE 57 a 83 a 54 a 54 a 46 a 43 a 43 a 43 a 14 a 33 a ALD+AC+0H 49 a 74 ab 43 a 34 a 31 ab 29 ab 29 ab 29 ab 0 b 0 b ALD+AC 20 be 77 ab 49 a 40 a 34 ab 31 ab 31 ab 31 ab 0 b 0 b ALD+OH 9 be 57 ab 14 b 11 be 6 cd 6 c 6 c 6 c 0 b 0 b ALD 29 b 74 ab 40 a 20 b 20 be 17 be 17 be 14 be 0 b 0 b AC 0 c 43 b 3 c 3 c 3 d 3 c 3 c 3 c 0 b 0 b OH 3 c 49 b 0 c 0 c 0 d 0 c 0 c 0 c 0 b CONTROL 0 c 37 b 0 c 0 c 0 d 0 c 0 c 0 c 0 b Means w i t h i n columns f o l l o w e d by same l e t t e r ( s ) are not s i g n i f i c a n t l y d i f f e r e n t 1-way ANOVA & Newman-Keuls, <* = 0.05 on transformed data ( a r c s l n ). 1 n = number of r e p l i c a t e s of 5 males each; 1e. when n = 7, 35 males were flown. 3 Cop. = c o p u l a t o r y behavior. 4 GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc i n d i c a t e d t h a t the ALD c o n t a i n e d some OH and the AC l u r e contained both ALD and OH contaminants. Table 13. The e f f e c t on the response of western spruce budworm male moths (lab-wild) in a wind tunnel, of adding 0.5% AC, 0.5% OH, or both, to 0.05% ALD. A l l components were formulated in 5 X 3 mm pvc rods. TREATMENT * MEAN PERCENTAGE BEHAVIORAL RESPONSE (n = 8) 1 , 2 Wing Take Lock Upwind 1m 1.5 m Touch Land Cop./n Cop./ 3 fan o f f on f l i g h t H land FEMALE 80 a 88 a 60 a 60 a 60 a 60 a 60 a 60 a 18 abc 32 ALD+AC+OH 70 ab 85 a 55 a 48 a 45 a 45 a 45 a 45 a 15 abc 35 ALD+AC 63 ab 90 a 58 a 58 a 58 a 58 a 58 a 55 a 33 a 30 ALD+OH 48 b 90 a 60 a 53 a 45 a 45 a 45 a 43 a 8 be 25 ALD 83 a 98 a 65 a 58 a 58 a 58 a 53 a 53 a 25 ab 49 AC 8 c 55 b 13 b 10 b 10 b 10 b 10 b 10 b 3 c 13 OH 3 c 40 b 8 b 8 b 8 b 8 b 5 b 5 b 0 c 0 CONTROL 3 c 20 c 0 b 0 b 0 b 0 b 0 b 0 b 0 c 0 Means within columns followed by same- l e t t e r ( s ) are not- s igni f i cant 1 y d i f f e r e n t , 1-way ANOVA & Newman-Keuls ot = 0.05 on transformed data ( a r c s i n / y ) • n = number of r e p l i c a t e s of 5 males each; 1e. when n = 8, 40 males were flown per treatment. Cop. = copulatory behavior. GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc lures i n d i c a t e d that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. 70 the wild moths where ALD+OH induced s i g n i f i c a n t l y less percentage locking-on than ALD alone (Table 12). Percentage wingfanning was also s i g n i f i c a n t l y reduced in the lab-wild moths with the same blend (Table 13). In the wild males, the ternary blend of 0.05% ALD + 0.5% AC + 0.5% OH s i g n i f i c a n t l y increased percentage wingfanning and upwind f l i g h t compared to the ALD alone (Table 12). Conversely, in the laboratory and lab-wild moths, the percentage response to the ternary blend was lower than that to ALD, but not s i g n i f i c a n t l y so (Tables 11,13). Response of the laboratory males was about the same to 0.05% ALD as i t was to a v i r g i n female (Table 11). This was not so with the wild males where percentage response to the v i r g i n female was s i g n i f i c a n t l y greater than to 0.05% ALD, in terms of wing-fanning, upwind f l i g h t , reaching the lure, and attempting copulation (Table 12). Addition of 0.5% AC or 0.5% AC + 0.5% OH to 0.05% ALD increased the percentage response of wild males to a l e v e l not s i g n i f i c a n t l y d i f f e r e n t from that to the v i r g i n female (Table 12). Responses of the lab-wild males were inconsistent; in some experiments (Tables 3, 13), the 0.05% ALD lure was about equal in attractiveness to the v i r g i n female, but in others (see below), the percentage response was s i g n i f i c a n t l y higher to the v i r g i n female. The e f f e c t of adding 0.005% or 0.05% of AC or OH, or both, was examined in the lab-wild males only. The v i r g i n female stimulated the greatest response in a l l behaviors except 71 copulatory behavior (Tables 14, 15). Percentage response to the v i r g i n female was s i g n i f i c a n t l y greater than that to 0.05% ALD for wing-fanning, upwind f l i g h t , and reaching the lure (Tables 14, 15). This i s further evidence that male moths may use other components in addition to the ALD when searching for a female. Adding 0.005% OH to 0.05% ALD s i g n i f i c a n t l y decreased percentage locking-on and upwind f l i g h t but s i g n i f i c a n t l y increased percentage attempted copulation (Table 15). The addition of 0.05% OH ( 7 X 3 mm pvc rod) to 0.05% ALD increased the percentage response of most behaviors s l i g h t l y , but not s i g n i f i c a n t l y (Table 14). Adding 0.005% AC to 0.05% ALD s i g n i f i c a n t l y increased percentage attempted copulation but otherwise had l i t t l e effect (Table 15). The addition of 0.05% AC (two 6.5 X 3 mm pvc rods) s i g n i f i c a n t l y increased the percentage of upwind f l i g h t and percentage of males reaching a 0.05% ALD lure (Table 14); because of contamination, th i s treatment was estimated to release ALD:AC:OH in a 10:3:6 r a t i o , which approximates that of a v i r g i n female. Addition of AC+OH, at concentrations from 0.005-0.5%, to 0.05% ALD brought the percentage response for a l l behavioral variables, except wing-fanning, very close to that to the v i r g i n female. The ternary blends, composed of 0.05% ALD plus either 0.05% AC + 0.05% OH or 0.005% AC + 0.005% OH, were s i g n i f i c a n t l y better than 0.05% ALD alone for stimulating upwind f l i g h t , landing at the lure and copulatory attempts (Tables 14, 15). T a b l e 14. The e f f e c t on t h e r e s p o n s e o f w e s t e r n s p r u c e budworm male moths ( l a b - w i l d ) i n a w i n d t u n n e l , o f a d d i n g 0.05% AC (two pvc r o d s , each 6.5 X 3 mm), o r 0.05% OH (7 X 3 mm pvc r o d s o r b o t h , t o 0.05% ALD (5 X 3 mm pvc r o d ) . Due t o i m p u r i t i e s o f OH and ALD i n t h e AC l u r e s , t h e ALD+AC c o m b i n a t i o n was e s t i m a t e d t o r e l e a s e t h e components a t about t h e same r a t e as a v i r g i n f e m a l e . TREATMENT 1 MEAN PERCENTAGE BEHAVIORAL RESPONSE (n = 8 ) 2 ' 3 Wing Take Lock Upwind 1 m 1.5 m Touch Land Cop./n Cop./ f a n o f f on f l i g h t tt l a n d FEMALE 55 a 95 a 80 a 78 a 75 a 75 a 75 a 73 a 20 ab 30 ab ALD+AC+OH 45 ab 93 a 80 a 78 a 73 a 70 a 70 ab 70 a 43 a 63 a ALD+AC 48 ab 93 a 85 a 75 a 73 a 68 a 65 ab 65 ab 38 ab 61 a ALD+OH 28 b 90 a 73 a 65 ab 58 ab 50 ab 50 be 45 be 25 ab 56 a ALD 35 b 90 a 63 a 48 b 45 b 40 b 35 c 35 c 20 be 54 a AC 3 c 45 be 10 b 10 c 10 c 10 c 8 d 8 d 0 c 0 b OH 0 c 58 b 15 b 15 c 13 c 13 c 8 d 8 d 0 c 0 b CONTROL 0 c 30 c 0 b 0 c 0 c 0 c 0 d 0 d 0 c GLC a n a l y s e s of c o l l e c t e d v o l a t i l e s f rom pvc l u r e s i n d i c a t e d t h a t t h e ALD l u r e c o n t a i n e d an OH c o n t a m i n a n t and t h a t t h e AC l u r e c o n t a i n e d b o t h ALD and OH c o n t a m i n a n t s . Means w i t h i n columns f o l l o w e d by same l e t t e r ( s ) a r e n o t s i g n i f i c a n t l y d i f f e r e n t , 1-way ANOVA & Newman-Keuls, « = 0.05 on t r a n s f o r m e d d a t a ( a r c s i n ,/y~ ) n = number o f r e p l i c a t e s o f 5 males each; i e . when N = 8, 40 males were f l o w n . Cop. = c o p u l a t o r y b e h a v i o r . Table 15. The e f f e c t on the response of western spruce budworm male moths (lab-wild) in a wind tunnel, of adding 0.005% AC, 0.005% OH, or both, to 0.05% ALD. A l l components were formulated in 5 X 3 mm pvc rods. TREATMENT * MEAN PERCENTAGE BEHAVIORAL RESPONSE (n = 8) Wing Take Lock Upwind 1m 1.5 m Touch Land Cop./n Cop./ fan o f f on f l i g h t H land FEMALE 85 a 95 a 85 a 85 a 85 a 85 a 85 a 85 a 50 a 59 a ALD+AC+OH 68 b 100 a 88 a 85 a 85 a 80 a 80 a 80 a 48 a 56 a ALD+AC 68 b 98 a 63 be 58 be 58 b 58 b 58 b 58 b 33 a 52 a ALD+OH 55 b 83 a 55 c 48 c 48 b 48 b 48 b 48 b 35 a 62 a ALD 53 b 90 a 75 ab 73 ab 60 b 55 b 55 b 55 b 10 b 15 b AC 3 c 40 b 0 d 0 d 0 c 0 c 0 c 0 c 0 b OH 0 c 35 b 0 d 0 d 0 c O c 0 c 0 c 0 b CONTROL 0 c 60 b 5 d 5 d 5 c 3 c 3 c 3 c 0 b 0 b Means within columns followed by same l e t t e r ( s ) are not s i g n i f i c a n t l y d i f f e r e n t , 1-way ANOVA & Newman-Keuls <* = 0.05 on transformed data ( a r c s i n •/y" ) n = number of r e p l i c a t e s of 5 males each; 1e. when N = 8, 40 males were flown. Cop. « copulatory behavior GLC analyses of c o l l e c t e d v o l a t l l e s from pvc lures Indicated that the ALD lure contained an OH contaminant and that the AC lure contained both ALD and OH contaminants. 74 Temporal response In the lab-wild males, the interval between release on the platform and taking-off was s i g n i f i c a n t l y longer in response to 0.5% AC or 0.5% OH than to any blend containing 0.05% ALD, or the v i r g i n females (Table 16). A similar trend was observed in the laboratory and wild males but with fewer s i g n i f i c a n t differences (Tables 34,35, Appendix I I ) . When 0.5% OH was added to 0.05% ALD, the duration of stationary zig-zag f l i g h t and the time from release of the moth to landing at the lure were both s i g n i f i c a n t l y increased in the wild males (Table 35, Appendix I I ) , but response to the same blend was not s i g n i f i c a n t l y d i f f e r e n t from 0.05% ALD in either the laboratory or lab-wild males. The addition of 0.5% AC to 0.05% ALD s i g n i f i c a n t l y increased the i n t e r v a l between f i r s t touching the lure and subsequently landing on i t but only in the lab-wild males (Table 16). The lab-wild males took s i g n i f i c a n t l y longer to begin wing-fanning in response to 0.05% ALD + 0.05% AC than to the v i r g i n females (Table 17). This was surprising because the combination of 0.05% ALD + 0.05% AC was estimated to resemble the blend and release rate of a v i r g i n female, and had e l i c i t e d similar percentage responses. This suggests that other components, such as 14:ALD or 14:AC, or perhaps some not previously detected in the female e f f l u v i a , may affect the male moths orientation and pre-mating behavior. The addition of 0.005% AC or 0.005% OH to 0.05% ALD had l i t t l e e f fect on temporal variables (Table 18). The mean net ground speed near the lure (0.5m-T) was s i g n i f i c a n t l y increased in lab-wild males when either 0.5% AC or Table 16. The temporal responses of western spruce budworm male moths ( lab -w i ld ) to various blends of 0.05% ALD, 0.5% AC, and 0.5% OH In a wind tunnel . Responses were compared with those to a v i r g i n female and a blank control lu re . Due to the small number of responders, data from AC, OH and CONTROL were not Included In ANOVA or means tes ts , except for the var iab le of R-TO. A l l components were formulated in 5 X 3 mm pvc rods. TREATMENT MEAN TIME INTERVAL (s) 2 , 3 n R-WF n R-TO n TO-LO n STAT.ZZ n T-L R-L n TO-L FEMALE 32 7 . 1 33 20 .5 b 23 ALD+AC+OH 28 6 . 1 34 12 .5 b 22 ALD+AC 24 4 .8 37 14 .8 b 22 ALD+OH 19 3 .6 36 18. . 1 b 24 ALD 33 7 .9 38 21 . 1 b 27 AC 3 1 3 22 51 .2 a 4 OH 1 0. .0 17 42. .7 a 3 CONTROL 1 0 .0 10 36. .6 ab 4 .3 23 1 .9 23 5 .6 ab 23 40 .9 23 26 .8 6 . 2 19 4 .5 18 8 2 ab 18 38 .9 18 30 .6 6 . 1 22 4 .9 20 11 . 1 a 20 48 .0 20 38 .5 4 . 2 22 4 .0 16 4. .9 ab 16 62 .3 16 48 .8 4 .4 24 6 .6 21 2. .6 b 21 49 .5 21 35 .0 4 .0 3 2 .3 3 0 0 3 91 .7 3 28 .7 8. 0 2 2. .0 1 0. 0 1 71 .0 1 21 . 0 GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc lures Indicated that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. Means wi th in columns fol lowed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, m • 0 . 0 5 . Data transformed by log(y + 1). R • Release on p lat form; WF » I n i t i a t i o n of wing-fanning; TO = Take o f f ; LO = Lock-on ( I n i t i a t i o n of 2lg - z a f l i g h t ) ; STAT.ZZ • Duration of s tat ionary z i g - z a g f l i g h t ; T • Touching lure cage; L = landing at lure cage. Table 17. The temporal responses of western spruce budworm male moths ( lab -w i ld ) to var ious blends of 0.05% ALD (5 X 3 mm pvc rod) , 0.05% AC (two pvc rods, each 6.5 X 3 mm), and 0.05% OH (7 X 3 mm pvc rod) 1n a wind tunnel . Due to Impurities of OH and ALD In the AC lures , the A10+AC combination was estimated to re lease the components at about the same rate of a v i r g i n female. Responses were compared with those to a v i r g i n female and a blank control lu re . Due to the small number of responders. data from AC, OH and the CONTROL were not Included In the ANOVA or means t e s t s , except for the var iab le of R-TO. TREATMENT MEAN TIME INTERVAL (s) 1 » 2 3 R-WF n R-TO n TO-LO n STAT.ZZ n T-L n R-L n TO-L FEMALE 23 5. .5 b 38 14 .9 31 3 .9 31 1 .7 28 4 . 1 28 34 .6 28 21 . 2 b ALD+AC+OH 18 a ,3 ab 37 16 .6 31 3 .2 31 2 .6 27 6 9 27 41 . 7 27 31 .0 b ALD+AC 19 18. .7 a 37 22. .4 33 5 . 1 33 2. .7 25 3 .0 25 50. .4 25 25 ,4 b ALD+OH 10 5 6 ab 36 19 .6 29 3. .3 28 3 .3 18 6 .6 18 54 .7 18 38 .7 a ALD 15 6 .8 ab 36 17 .7 25 4 .0 24 7 .3 14 4 .6 14 55 .5 14 48 .9 a AC 2 4. .0 18 22 .3 4 2 .5 4 1 .5 3 8 .7 3 89 .7 3 45 .7 OH 23 27 .8 6 3. . 5 5 0. 0 3 9. .3 3 68. .3 3 35 .0 CONTROL 13 37. .4 1 Means with in columns fol lowed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, ot • 0 . 0 5 . Data transformed by log(y + 1). R = Release on p lat form; WF « I n i t i a t i o n of wing-fanning; TO • Take o f f ; LO • Lock-on ( I n i t i a t i o n of z i g - z a g f l i g h t ) ; STAT.ZZ » Duration of stat ionary z i g - z a g f l i g h t ; T = Touching lure cage; L » landing at lure cage. S i g n i f i c a n t treatment e f f e c t (ANOVA) but means not separable by Newman-Keuls. Table 18. The temporal responses of western spruce budworm male moths ( lab -w i ld ) to various blends of 0.05% ALD. 0.005% AC. and 0.005% OH In a wind tunnel . Responses were compared with those to a v i r g i n female and a blank control lure . Due to the small number of responders. data from AC. OH and CONTROL were not Included In ANOVA or means t e s t s , except for the var iab le of R-TO. Al t components were formulated in 5 X 3 mm pvc rods. TREATMENT MEAN TIME INTERVAL ( s ) 2 » 3 n R-WF n fi- •TO n TO--LO n STAT.ZZ n T--L n R--L n TO-L FEMALE 32 2.0 37 l l .9 b 33 7 .2 33 2.3 33 4 .2 33 39 .8 33 27 .8 ALD+AC+OH 28 2.5 41 8 .4 b 36 7 .6 36 1.3 33 4 .8 33 39 . 1 33 29.6 ALD+AC 27 4 .O 39 10 .7 ab 25 3 .7 24 4.0 23 5 .6 23 38 .6 23 29.6 ALD+OH 21 4.3 31 9 .8 b 21 5 .8 21 4. 1 18 2 .4 18 44 .9 18 32.4 ALD 22 7.0 36 12 .7 b 30 5 . 1 30 2.2 22 5 .0 22 43 .0 22 35.3 AC 1 2 .0 16 19. . 1 ab OH 13 18. .4 ab CONTROL 24 22. 8 a 1 3 .0 1 0 .0 1 GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc lures indicated that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. Means with in columns fol lowed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, « = 0 . 0 5 . Data transformed by log (y + 1). 3 R = Release on p lat form; WF » I n i t i a t i o n of w1ng-fannlng; TO = Take o f f ; LO •= Lock-on ( I n i t i a t i o n of ztg -2ag f l i g h t ) ; STAT.ZZ • Duration of s tat ionary z i g - z a g f l i g h t ; T = Touching lure cage; L = landing at lure cage. 78 0.5% AC + 0.5% OH were added to 0.05% ALD, whereas the addition of 0.5% OH did not have the same effect (Table 19). The same effects were not observed in the laboratory or wild males (Tables 36,37, Appendix I I ) . The mean net ground speed of lab-wild males, at a l l three recorded distances from the lure, was s i g n i f i c a n t l y increased by the addition of either 0.05% AC or 0.05% AC + 0.05% OH to 0.05% ALD; ground speeds in response to these blends were not s i g n i f i c a n t l y d i f f e r e n t from those to the v i r g i n females (Table 20). However, adding 0.05% OH to 0.05% ALD did not increase net ground speed (Table 20). The net ground speed from 0.5 m to the lure was not s i g n i f i c a n t l y increased by adding 0.005% AC or 0.005% OH, or both, to 0.05% ALD, but speed in response to the 0.05% ALD + 0.005% AC blend was not s i g n i f i c a n t l y d i f f e r e n t from that in response to the v i r g i n females (Table 21). F i e l d bioassays A. Trap catch vs ALD concentration There was a positive linear relationship between catch/trap and ALD concentration (log(x*10 4))(r = 0.61) but mean trap catch was not s i g n i f i c a n t l y d i f f e r e n t between 0.005% and 0.5% ALD concentrations (Fig. 14). Larger differences in catch between concentrations might have been found using high-capacity traps because the sticky traps were probably affected by saturation. The number of moths caught in the trap baited with the v i r g i n female was intermediate between those caught with 0.0005% and 0.005% ALD. This was lower than would be predicted from the Table 19. The net ground speed of f l i g h t of adult male western spruce budworms (lab-wild) in response to blends of 0.05% ALD, 0.5% AC, and 0.5% OH in a wind tunnel Speed was measured 1n three sections of the tunnel and averaged from the s t a r t of sta t i o n a r y zig-zag (LO-T) and the s t a r t of upwind f l i g h t (UF-T). A l l components were formulated in 5 X 3 mm pvc rods. TREATMENT1 MEAN NET GROUND SPEED OF FLIGHT (cm/s) 2 4 3 n 2m-1m n 1m-0.5m n 0.5m-T n UF-T n LO-T FEMALE 23 33, .6 23 19, .0 23 1 1 .0 ab 23 16, .7 23 14 . 7 ALD+AC+OH 17 26, . 1 18 18 .8 18 15 . 3 a 16 17 , 2 16 15. .7 ALD+AC 22 27, .9 22 17, .4 22 15 .9 a 22 18 , .3 22 14 . 9 ALD+OH 17 32, .9 16 13 .6 16 7 . 3 c 16 12, .4 16 10, .5 ALD 23 21 , . 2 23 14 .6 22 8, .5 be 22 12, .6 22 10. .5 AC 3 46, . 7 3 9. .6 3 4, .5 3 9, . 3 3 8 . 7 OH 2 36. , 1 2 8 . 3 1 8 . , 3 1 14 , .3 1 1 1 . 8 GLC a n a l y s i s of vol at 11es col 1ected from pvc lures indicated that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. Means within columns followed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls, <* = 0.05. S i g n i f i c a n t treatment e f f e c t (ANOVA o< = 0.05) but means not separable by Newman-Keuls. Distance from the pheromone source. Table 20. The net ground speed of f l i g h t of a d u l t male western spruce budworms ( l a b - w i l d ) 1n response to blends of 0.05% ALD (5 X 3 mm pvc r o d ) , 0.05% AC (two pvc rods, each 6.5 X 3 mm), and 0.05% 0H (7 X 3 mm pvc rod) i n a wind tu n n e l . Due to i m p u r i t i e s of 0H and ALD i n the AC l u r e s , the ALD+AC combination was estimated to r e l e a s e the components at about the same r a t e as th a t of a v i r g i n female. Speed was measured i n three s e c t i o n s of the tunnel and averaged from the s t a r t of s t a t i o n a r y z i g - z a g f l i g h t (LO-T) and the s t a r t of upwind f l i g h t (UF-T). , 2 TREATMENT 1 MEAN NET GROUND 5PEED OF FLIGHT (cm/s) 3 n 2m-1m n 1m-0.5m n 0.5m-T n UF-T n LO-T FEMALE ALD+AC+OH ALD+AC ALD+OH ALD AC OH 25 27.3 a 27 24.4 ab 28 24.3 ab 23 15.9 be 18 12.3 c 3 14.1 4 13.8 27 23. 1 a 27 18.6 a 26 17.6 a 20 10.7 b 15 9.6 b 4 9.7 4 12.2 27 16.5 a 27 12.8 a 25 12.2 ab 20 8.0 be 15 6.8 c 3 3.2 2 7.4 27 1 8 . 1 a 27 16.3 a 25 14.7 a 20 9.6 b 13 8.7 b 3 6.2 2 6.9 27 17.6 a 27 15.3 a 25 13.3 a 20 8.9 b 13 7.8 b 3 6.1 2 6.9 I GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc l u r e s I n d i c a t e d that the ALD l u r e s c o n t a i n e d some OH and the AC l u r e s c o n t a i n e d both ALD and OH contaminants. 2 Means w i t h i n columns f o l l o w e d by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls, <* = 0.05. 3 Distance from the pheromone source. Table 21. The net ground speed of f l i g h t of adult male western spruce (lab-wild) in response to blends of 0.05% ALD, 0.005% AC, and 0.005% OH in a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the s t a r t of stationary zig-zag (LO-T) and the s t a r t of upwind f l i g h t (UF-T). A l l components were formulated in 5 X 3 mm pvc rods. TREATMENT1 MEAN NET GROUND SPEED OF FLIGHT (cm/s) 2 n 2m--1m 4 n 1m-0. 5m n 0. 5m--T n UF--T 3 n LO--T FEMALE 30 27. .6 34 21 .0 34 17 .8 a 31 18 , .0 31 15, .4 ALD+AC+OH 32 23. .0 32 16 .5 32 12 . 1 b 31 14 . 9 31 14 , . 2 ALD+AC 33 23. .6 23 18 .8 23 15 .0 ab 23 17. .5 23 14, .9 ALD+OH 18 22 . ,0 18 16 .0 18 1 1 .7 b 18 13 . , 2 18 12 , .0 ALD 23 28. ,4 22 16 .2 22 8 . 1 b 22 13, , 1 22 12, .2 GLC a n a l y s i s of v o l a t l l e s c o l l e c t e d from pvc lures Indicated that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. Means within columns followed by d i f f e r e n t l e t t e r ( s ) are s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls, ot = 0.05. S i g n i f i c a n t treatment e f f e c t (ANOVA <x = 0.05) but means not separable by Newman-Keuls. Distance from the pheromone source. 90 I c ' i I O !c o z 2 80 -70 -60 -50 40 30 20 10 -• ab FEMALE I ab I • 1 1 0.0005 T T 0.005 0.05 CONCENTRATION OF AID (% IN PVC) ~~\— 0.5 Fig. 14. Mean catch/trap (±S.E.) of western spruce budworm moths in sticky traps baited with ALD at concentrations from 0.0005% to 0.5%, or two virgin female budworm/trap. The regression of catch/trap vs ALD concentration (log(x(10000))) was significant (P ^  0.01; r 2 = 0.37). Different letters adjacent to the means denote s i g n i f i c a n t l y different trap catch (ANOVA £. Newman-Keuls, <x = 0.05). oo 83 wind tunnel bioassays which showed that the v i r g i n female e l i c i t e d greater upwind f l i g h t and landing than a l l concentrations of ALD tested. In similar f i e l d studies with C. fumiferana, Sanders (1981b) found that the v i r g i n female was about equal in attr a c t i o n to a 0.03% ALD lure (10 x 3 mm pvc o rod). B. Comparisons of blends The trap catch was s i g n i f i c a n t l y reduced by adding 0.5% AC to 0.05% ALD (Table 22). Addition of 0.005-0.5% OH to 0.05% ALD also reduced the trap catch but not s i g n i f i c a n t l y (Table 23). The ternary blend of 0.05% ALD + 0.005% AC + 0.005% OH caught 49% more moths than 0.05% ALD in one test (Table 24) but only 6% more in another (see below); the differences were not si g n i f i c a n t in either t e s t . Adding saturated aldehyde (14:ALD) or acetate (14:AC) to 0.05% ALD had l i t t l e e f fect on trap catch but 14:ALD alone caught s i g n i f i c a n t l y more males than did a blank control (Tables 38, 39, Appendix I I ) . The addition of 0.005% AC + 0.0005% 14:ALD to 0.05% ALD improved trap catch by about 30% in one test (Table 40, Appendix II) but not in another (Table 42, Appendix II) and in neither case were the differences s i g n i f i c a n t . S i m i l a r l y , trap catch was improved 50% by adding 0.005% AC + 0.0005% 14:AC to 0.05% ALD in one test (Table 41, Appendix II) but was s l i g h t l y decreased in another (Table 42, Appendix I I ) . At the concentrations tested, the catch in traps baited with 0.05% ALD was not s i g n i f i c a n t l y changed by adding AC+OH+14:ALD, AC+OH+14:AC or AC+OH+14:ALD+14:AC (Table 42, 84 Table 22. The effect of adding 0.005-0.5% AC to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (8 X 8)(24-27 July 1984). Treatment Trap catch (n=8) Mean 1 S.E. ALD(0.05%) + ALD(0.05%) 54.9 7.1 a ALD(0.05%) 50. 1 6.4 a ALD(0.05%) + AC(0.005%) 48.4 5.3 a ALD(0.05%) + AC(0.05%) 38.9. 5.3 a ALD(0.05%) + AC(0.5%) 24.3 4.2 b Vir g i n Female ' 20.1 1.8 b AC(0.005%) 2.6 1.8 c Control 0.5 0.2 d Means followed by the same l e t t e r are not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (<* = 0.05). Analysis performed on transformed data (log(y+1)) 85 Table 23. The e f f e c t of a d d i n g 0.005-0.5% OH t o 0.05% ALD, on the c a t c h of w i l d w e s t e r n spruce budworm male moths i n t r i a n g u l a r s t i c k y t r a p s . A l l components were f o r m u l a t e d i n 5 X 3 mm pvc r o d s . The t r a p s were s e t out i n a t i m e - r e p l i c a t e d l a t i n square d e s i g n (8 X 8)(26-30 J u l y 1984). Treatment Trap c a t c h (n=8) Mean 1 S.E. ALD(0.05%) + ALD(0.05%) 32.6 4.2 a ALD(0.05%) 30.4 2.1 a ALD(0.05%) + OH(0.005%) 24.8 5.7 a ALD(0.05%) + OH(0.05%) 22.9 3.9 a ALD(0.05%) + OH(0.5%) 17.3 2.8 a V i r g i n female 12.5 3.5 b OH(0.05%) 0.6 0.3 c C o n t r o l 0.2 0.1 c Means f o l l o w e d by the same l e t t e r a r e not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (c* = 0.05). A n a l y s i s p erformed on t r a n s f o r m e d d a t a (log.(y+l)) 86 Table 24. The e f f e c t of adding 0.005% OH, 0.005% AC, or both, to 0.05% ALD, on the c a t c h of w i l d western spruce budworm male moths i n t r i a n g u l a r s t i c k y t r a p s . A l l components were formulated i n 5 X 3 mm pvc rods. The t r a p s were set out i n a t i m e - r e p l i c a t e d l a t i n square design (7 X 7)(28 J u l y - 3 August 1984). Treatment Trap c a t c h (n=7) Mean S . E . ALD(0.05%) + AC(0.005%) + OH(0.005%) ALD(0.05%) 47.6 32.0 1 1 . 0 a 3.8 ab ALD(0.05%) + ALD(0.05%) ALD(0.05%) + OH(0.005%) ALD(0.05%) + AC(0.005%) V i r g i n female 22.6 30.4 29.4 30. 1 7.6 ab 6.4 ab 7.9 b 7.2 ab AC(0.005%) + OH(0.005%) 0.6 0.4 c Means followed by the same l e t t e r are not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (o< = 0.05). A n a l y s i s performed on transformed data ( l o g ( y + l ) ) 87 Appendix I I ) . In almost a l l the f i e l d experiments, traps baited with v i r g i n females caught fewer moths than those baited with 0.05% ALD or combinations of ALD with other components. Table 25 summarizes the effects of the various minor components on trap catch of male moths. MONITORING WITH PHEROMONE TRAPS Factors a f f e c t i n g catches A. Age of lures The catch was not s i g n i f i c a n t l y d i f f e r e n t in traps baited with 0.05% ALD lures aged from 1-5 weeks (Fig. 15a) but in the traps baited with 0.0005% ALD i t decreased s i g n i f i c a n t l y after three weeks (Fig. 15b}. The western spruce budworm's f l i g h t season t y p i c a l l y l a s t s about four weeks. Therefore, the 0.05% ALD lure i s adequate for monitoring the entire f l i g h t season but the 0.0005% lure i s not. In similar experiments, Sanders (1981b) found no s i g n i f i c a n t difference in catches of C. fumiferana in Pherocon 1 CP sticky traps baited with 96/4 E/Z ALD lures (0.03%) aged from one to seven weeks. However, in a subsequent study, Sanders and Meighen (1987) reported a si g n i f i c a n t decline in release rate and trap catch using 0.03% 95/5 E/Z ALD lures aged up to six weeks. It i s possible that the attractiveness of the 0.05% ALD lures also decreased with age, but that s i g n i f i c a n t differences were obscured by trap saturation in the traps baited with fresher lures. Mean catch (SD) in the traps baited with 0.05% ALD lures, aged 7 d, was 40 8 8 Table 25. The a c t i v i t y of the minor components, AC, OH, 14:ALD, and 14:AC, of the western spruce budworm pheromone as measured by trap catch in the f i e l d . The components were rated as follows: + = s i g n i f i c a n t l y positive e f f e c t , - = s i g n i f i c a n t l y negative e f f e c t , (+) and (-) denote possible but not s i g n i f i c a n t p o s i t i v e and negative e f f e c t s respectively, and 0 = no e f f e c t . Component (% cone) A c t i v i t y  Alone 1 Added to 0.05% ALD 2 AC(0.5%) -AC(0.05%) 0 AC(0.005%) + 0 OH(0.5%) (-) OH(0.05%) 0 0 OH(0.005%) 0 14:ALD(0.0005,0.005%) + 0 14:AC(0.005%) 0 0 AC(0.005%) & OH(0.005%) (+) AC(0.005%) & 14:ALD(0.0005%) + 0 AC(0.005%) & 14:AC(0.005%) 0 OH(0.005%) & 14:AC(0.005%) 0 AC(0.005%) & OH(0.005%) & 14:ALD(0.005%) 0 AC(0.005%) & OH(0.005%) & 14:AC(0.005%) 0 AC(0.005%) & OH(0.005%) & 14:AC(0.005%) & 14:ALD(0.0005%) 0 Compared to an unbaited trap; ANOVA & Newman-Keuls (<x = 0.05). Compared to 0.05% ALD; ANOVA & Newman-Keuls (<* = 0.05). 89 I c X z s 60 50 -40 -30 -20 -10 -T B. 0.0005X ALD L L / 1 1 1 a A 1 Tb +*~^ . i i 20 40 60 AGE OF LURE (DAYS) F i g . 15. The e f f e c t of age of ALD l u r e s ( i n p v c ) on mean c a t c h i n s t i c k y t r a p s (n=7). L u r e s were aged i n a fume hood. A. 0.05% ALD. B. 0.0005% ALD. D i f f e r e n t l e t t e r s a d j a c e n t t o t h e means d e n o t e s i g n i f i c a n t l y d i f f e r e n t t r a p c a t c h (ANOVA & Newman-Keuls, <* = 0.05). 90 (25), which suggests that trap saturation probably occurred. Also, these lures were aged in a fume hood but aging i s probably faster in the f i e l d due to higher daytime temperatures and a greater chance of exposure to u l t r a v i o l e t l i g h t . These experiments should be repeated using a high-capacity trap, such as the Uni-trap. B. Trap height and proximity to foliage Mean catch/trap (± SD) was s i g n i f i c a n t l y greater in upper traps (70 ± 41) than in lower traps (29 ± 17) but the c o e f f i c i e n t of variation was the same (59%) at both heights. The mean catch/trap was also s i g n i f i c a n t l y greater in traps hung from host trees (222 + 49) than in traps hung in the open (80 ± 72). Unexpectedly, the c o e f f i c i e n t of variation of trap catch was much higher for traps in the open (90%) than for traps in trees (22%). C. Trap design Comparisons of designs There were no s i g n i f i c a n t differences in catch between any of the trap designs but the standard funnel traps caught more moths than did the mini-funnel or half-mini-funnel (Table 26). There was also l i t t l e difference in the c o e f f i c i e n t s of v a r i a t i o n between the traps except in the second experiment where that of the half-mini-funnel was noticeably lower than those of the other traps. 91 Table 26. Comparison of high-capacity pheromone traps for the western spruce budworm. Five designs were compared in two experiments (A and B) set out in l a t i n squares (4 X 4). Traps were baited with a crude blend of E/Z 11-tetradecenal, The lure was suspended between the fourth and f i f t h funnel of the funnel and half-funnel trap in experiment A; but was suspended just above the c o l l e c t i n g jar in experiment B. Expt. Trap Design Mean catch/trap CV. 1 (%) A. Half-funnel 87 23 Funnel 95 33 Kendall 64 27 Mini-funnel 55 31 B. Funnel 303 37 Half-funnel 286 55 Kendall 242 55 Half-mini-funnel 120 24 CV. = Coefficient of v a r i a t i o n . 92 The average c a t c h was much higher i n the second experiment (238 moths/trap) than i n the f i r s t (75 moths/trap) even though both experiments were run f o r about 24 h and on c o n s e c u t i v e days. Temperatures d u r i n g the peak f l i g h t p e r i o d averaged s l i g h t l y higher on the day of the second experiment (26 C) compared with the f i r s t (24 C) but were w e l l above the budworm's f l i g h t t h r e s h o l d of 12-13 C (Shepherd 1979) on both days. The i n c r e a s e i n c a t c h i n the second experiment may have been due to an i n f l u x of d i s p e r s i n g males c a r r i e d on the down-valley winds. An average of 16 moths/trap (22% of t o t a l catch) were caught between 1200 and 1430 PST. T h i s c o n f l i c t s with Shepherd (1979) and L i e b h o l d and Volney (1984b) who found that t r a p s caught western spruce budworm males l a r g e l y between 1800 and 2400 PST. Budworm d e n s i t y was high i n the f i e l d p l o t s and i t i s p o s s i b l e that some or a l l of the midday catches were due to males a c c i d e n t a l l y stumbling i n t o the t r a p s r a t h e r than a c t u a l l y responding to pheromone. Evidence f o r t h i s was a c a t c h of 20 moths i n one night i n an unbaited K e n d a l l t r a p . However, the unbaited t r a p had been b a i t e d i n p r e v i o u s experiments and c o u l d have been contaminated with pheromone. Because f i r m c o n c l u s i o n s c o u l d not be made re g a r d i n g the midday c a t c h e s , a d d i t i o n a l o b s e r v a t i o n s of the male moth d i u r n a l p e r i o d i c i t y of response were made the f o l l o w i n g y e a r . Small numbers of moths were caught from 700 to 1500 PST but peak catches o c c u r r e d between 1800 and 2100 PST; about 2 h before to 2 h a f t e r sunset (about 2000 PST). T h i s was s i m i l a r to 93 Shepherd's (1979) results but the peak was about 1 h e a r l i e r . P e r i o d i c i t y of catch in traps baited with v i r g i n females was the same as that in traps baited with 0.05% ALD (Fig. 26, Appendix I I I ) . Shepherd (1979) also noted the l a t t e r phenomenon and suggested that the time of mating was determined by the male moth rather than the female. If t h i s i s true, i t means that catch in synthetic-baited traps w i l l not be biased by a t t r a c t i n g males at times outside of the natural mating period, and would therefore stand a better chance of being related to the l e v e l of budworm mating. E f f i c i e n c y Trapping e f f i c i e n c y decreased with cumulative catch in the sticky trap (Fig. 16). When fresh, the sticky trap caught 10 of the f i r s t 11 moths that landed on i t (91% e f f i c i e n t ) but e f f i c i e n c y subsequently dropped to about 35%. The decrease in e f f i c i e n c y after only ten males were caught was probably due to the accumulation on the adhesive of wing scales from captured moths (Shepherd 1979). E f f i c i e n c y was noticeably increased when the trap was rotated 180° because the end formerly facing upwind was not covered with moths. The tendency for moths to be trapped mainly in the downwind end of the trap was noted previously in western spruce budworm male moths orienting to pheromone-baited sticky boards, and i s simply a result of the moths f l y i n g upwind in response to pheromone (Shepherd 1979). Although the sticky trap was s t i l l about 35% e f f i c i e n t with a cumulative catch of 70 moths, e f f i c i e n c y would probably have decreased to zero at around 100-150 moths. This 100 20 H 10 -0 _) 1 1 1 1 1 1 1 0 20 40 60 80 CUMULATIVE CATCH F i g . 16. Effect of cumulative catch of western spruce budworm male moths on the e f f i c i e n c y of the sticky trap baited with 0.05% ALD. J S 95 agrees with other studies using sticky traps (Shepherd 1979; Sanders 1981a; Houseweart et a l . 1981). The placement of dichlorvos near the lure instead of in the c o l l e c t i n g bucket of the Uni-trap was hypothesized to make i t more e f f i c i e n t due to quicker knockdown of landed moths. This proved f a l s e . Regardless of the placement of dichlorvos, the Uni-trap caught about 56% of the moths that landed on i t compared with 71% for the Multi-Pher trap but the difference was not s i g n i f i c a n t (Table 27). The s l i g h t l y higher e f f i c i e n c y in the Multi-Pher may be due to i t s shuttlecock-like perch which surrounds the pheromone lure . Budworm males were often observed wingfanning and resting on t h i s perch and could conceivably have had more opportunity to be overcome by dichlorvos than in the Uni-trap. Of moths approaching within 1 m, a s i g n i f i c a n t l y smaller percentage landed on the Multi-Pher trap (59%) than on either Uni-trap (82% and 90%) (Table 27). Moths observed f l y i n g an upwind zig-zag path towards the Multi-Pher trap were often observed to veer off and f l y away. Lewis and McCauley (1976) showed that t o t a l catch of the pea moth, Cydia nigricana (Steph.), in various traps, was p o s i t i v e l y correlated with plume l i n e a r i t y . It i s possible that the structure of the plume near the Uni-trap was more suitable for the budworm's orientation either by virtue of trap design or by the influence of surrounding vegetation. Different v i s u a l cues near the traps may also have affected the orientation and landing behavior of Table 27. E f f i c i e n c y of three high-capacity traps for trapping western spruce budworm In the f i e Each percentage is a mean of f i v e r e p l i c a t e s of 10 males approaching within 1 m of the trap , Trap No. landing X No. within 1 m 100/ No. caught X No. within 1 10O/ m No. caught X No. landed on 100/ trap Mean 1 SD c v . 2 Mean SD CV. Mean SD C V Uni-trap, dichlorvos In c o l l e c t l n g Jar 82 a 8 10 47 a 12 25 56 a 12 21 Uni-trap, dichlorvos near lure and In c o l l e c t l n g Jar 90 a 7 8 52 a 21 40 58 a 25 43 Multi-Pher trap. 59 b 14 25 43 a 21 49 71 a 18 26 dichlorvos 1n c o l l e c t I n g Jar Means within column followed by d i f f e r e n t l e t t e r s are s i g n i f i c a n t l y d i f f e r e n t ; ANOVA and Newman-Keuls a = 0.05. C V . » C o e f f i c i e n t of va r i a t i o n . 97 the moths. The difference in the percentage of locked-on moths reaching the trap may have been due to a position e f f e c t rather than to a design difference. The trap positions should have been re-randomized before each r e p l i c a t e but because the traps were part of R.F. Shepherd's and T.G. Gray's existing experiment t h i s was not possible. In any case, the s l i g h t l y higher catch of moths that landed on the Multi-Pher trap compensated enough so that the percentage of moths caught that approached within 1 m was not s i g n i f i c a n t l y d i f f e r e n t for the three traps (Table 27). The Uni-trap with dichlorvos in the c o l l e c t i n g bucket only had the lowest c o e f f i c i e n t of v a r i a t i o n for a l l variables of trapping e f f i c i e n c y which suggests that i t was the most consistent of the traps and the most suitable for population monitoring (Table 27). Sanders (1986a), however, found that the c o e f f i c i e n t s of variation of trap catch (not trapping e f f i c i e n c y ) were similar for the Uni-trap and the Multi-Pher trap. Only 22% of budworm male moths approaching a Uni-trap baited with 0.5% 92/8 E/Z ALD were caught, compared with 50% for the other concentrations tested (Table 28). Once the moths reached the trap, the number caught was unaffected by pheromone concentration. The percentage of moths caught of those that landed on the Uni-trap was the same (50%) at a l l four pheromone concentrations (Table 28). Reductions in the numbers of moths caught that approach a trap, when pheromone concentration i s 98 Table 28. The e f f e c t of ALD c o n c e n t r a t i o n on e f f i c i e n c y of the U n i - t r a p f o r t r a p p i n g a d u l t male western spruce budworm. Twelve males were r e l e a s e d to each treatment i n the wind t u n n e l . Lure n 1 No. caught/ % No. caught/ 0 . "6> No. w i t h i n 1 m No. l a n d i n g on t r a p V i r g i n female 4 1/4 25 1/4 25 0.5% 9 2/9 22 2/4 50 0.05% 10 5/10 50 5/10 50 0.005% 5 2/4 50 2/4 50 0.0005% 6 1/2 50 1/2 50 n = the number of moths that locked-on. 99 increased, have also been observed in the Indianmeal moth, Plodia interpunctella (Hubner) (Mankin et a_l. 1 983) and the Oriental f r u i t moth (Baker and Roelofs 1981). Surprisingly, the v i r g i n female caught only one of four males that landed on the trap but the significance of t h i s i s questionable, given the low number of observations. A trapping e f f i c i e n c y of 50% agrees well with the mean ef f i c i e n c y of 56% found for the Uni-trap in the f i e l d and lends support to the extrapolation of wind tunnel results to the f i e l d . In other wind tunnel experiments, Sanders (1986a) found that 82% of C. fumiferana males entering a Uni-trap were caught. The lower e f f i c i e n c y which I found could be due to differences in procedure. Sanders (1986a) observed the moths for 5 min once they had landed on the trap, instead of 3 min, he used a lower wind speed (25 cm/s) and he placed dichlorvos in the c o l l e c t i n g . j a r . Design, pheromone concentration and maintenance Analysis of the combined data from a l l 15 plots, as a replicated l a t i n square, revealed a s i g n i f i c a n t interaction between treatments and plots (squares)(P 4 0.05) and the data were therefore analyzed separately in each p l o t . The l a t i n square design was j u s t i f i e d s t a t i s t i c a l l y in only three plots (3, 4, and 10) which had both s i g n i f i c a n t row and column e f f e c t s . A l l plots except 5, 6, 7 and 15 had s i g n i f i c a n t row effects (Table 29). The lack of s i g n i f i c a n t column e f f e c t s in a l l but three plots suggests Table 29. Mean catch (n • 8) of western spruce budworm moths In eight d i f f e r e n t trap systems In each of f i f t e e n p l o t s . The trap systems were a combination of two trap designs (Uni - t rap vs Tr iangular s t i c k y t rap ) , two concentrat ions of ALD (0.05% vs 0.0005%) In pvc, and two maintenance regimes (traps cleaned every two days (M) vs moths accumulated In trap a l l season (NM)). Trap System Plot No. 1 2 3 4 5 6 7 8 9 10 1 1 12 13 14 15 St icky 43 a 86 a 73 a 61 a 116 a 104 a 91 a 86 a 116 a 98 a 74 a 75 a 68 a 75 a 59 a 0.05% M Un i - t rap 34 ab 67 a 20 b 36 b 75 a 38 b 66 ab 117 a 98 a 90 a 41 b 107 a 36 b 31 b 18 b 0.05% M U n i - t r a p 28 ab 38 a 17 be 31 b 37 ab 22 b 38 abc 53 a 51 ab 59 ab 42 b 41 b 38 b 26 b 25 b 0.05% NM St icky 11 cd 10 b 14 cd 13 b 12 c 8 c 13 cde 13 b IO c 12 cd 15 c 8 c 14 c 19 be 23 be 0.05% NM St icky 18 be 29 a 4 de 3 c 23 be 6 c 18 bed 12 b 29 be 24 be 5 d 13 c 5 cd 11 cd 11 bed 0.0005% M St icky 4 de 7 b 2 ef I c 7 c 6 c 11 cde 7 b 8 c 11 cd 3 d 4 c 2 de 6 de 8 bed 0.0005% NM U n i - t r a p 1 e 6 b 1 f g 2 c 10 c I c 3 e 5 b 14 c 16 cd 3 d 6 c O f 3 e 3 d 0.0005% M Un1-trap 3 de 3 b O g 1 c 8 c 2 c 4 de 5 b 13 c 6 d 3 d 5 c 1 ef 6 de 6 cd 0.0005% NM Means with in columns fol lowed by d i f f e r e n t l e t t e r s are s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls on transformed data (1og(y + 1)) , £ $ 0 . 0 5 . t-1 o o 101 that i n most p l o t s there were no t r a p p o s i t i o n s c o n s i s t e n t l y a s s o c i a t e d with h i g h c a t c h e s . R e l a t i v e mean c a t c h i n the d i f f e r e n t t r a p systems v a r i e d between p l o t s (Table 29) as d i d the number of f i r s t - and second-order i n t e r a c t i o n s between t r a p design, pheromone c o n c e n t r a t i o n , and maintenance regime (Table 30). The i n t e r a c t i o n s between the t r a p p i n g system f a c t o r s are shown g r a p h i c a l l y f o r p l o t 6 ( F i g . 17). Maintenance s i g n i f i c a n t l y improved c a t c h i n the s t i c k y t r a p but only when b a i t e d with 0.05% ALD ( F i g . 17.A). Maintenance d i d not a f f e c t mean c a t c h i n the U n i - t r a p at e i t h e r c o n c e n t r a t i o n ( F i g . 17.B) but the cumulative season's c a t c h i n the U n i - t r a p s was a f f e c t e d by maintenance (see below). Looking at the same data from a d i f f e r e n t angle shows that when both t r a p s were b a i t e d with 0.05% ALD and were maintained, the s t i c k y t r a p caught s i g n i f i c a n t l y more moths than the U n i - t r a p ( F i g . 17.C). The r e v e r s e was t r u e when t r a p s were not maintained ( F i g . 17.D). Traps b a i t e d with 0.05% ALD n e a r l y always caught more moths than t r a p s b a i t e d with 0.0005% ALD. The exception was that maintained s t i c k y t r a p s b a i t e d with 0.0005% ALD sometimes caught more moths than non-maintained s t i c k y t r a p s b a i t e d with 0.05% ALD, due to t r a p s a t u r a t i o n i n the l a t t e r ; the t o t a l season's c a t c h was not s i g n i f i c a n t l y d i f f e r e n t between these treatments. The U n i - t r a p b a i t e d with 0.0005% ALD caught very few moths which suggests that i t would not be s e n s i t i v e enough to monitor very low budworm d e n s i t i e s . Table 30. Summary of the f a c t o r i a l experiment comparing d i f f e r e n t pheromone trapping systems for the capture of western spruce budworm male moths. The experiment was set out In a l a t i n square and r e p l i c a t e d In 15 p l o t s . The s i g n i f i c a n t fac tors and Interact ions are marked (*) In each p l o t . Three-way ANOVA on transformed data , (1og(y+1)), P = 0 . 0 5 . P lot No. Trap ALD Trap Trap X Trap X Cone. X Trap X Cone. Row Column Design Cone. Ma in t . Cone Maint. Ma Int. X Ma Int. 1 0 3 A. S t i c k y B" U n i - t r a p , I I 0 0 0 0 0 5 % 0 . 0 5 % 0 . 0 0 0 5 % 0 . 0 5 % CONCENTRATION OF ALD (% i n pvc) F i g . 17. Graphs showing t h e i n t e r a c t i o n between t r a p d e s i g n , pheromone r e l e a s e r a t e , and m a i n t e n a n c e r e g i m e , f o r t r a p p i n g t h e w e s t e r n s p r u c e budworm. P l o t 6 i s u s e d a s an examp l e . Each g r a p h shows mean c a t c h / t r a p (n = 8 ) ( l o g y) o f t h e d i f f e r e n t t r e a t m e n t s . A. S t i c k y t r a p s , B. U n i - t r a p s , C. T r a p s m a i n t a i n e d , D. T r a p s n o t m a i n t a i n e d . W i t h i n e ach p l o t , d i f f e r e n t l e t t e r s a d j a c e n t t o means i n d i c a t e s s i g n i f i c a n t d i f f e r e n c e s (ANOVA and Newman-Keuls = 0.05). M = M a i n t a i n e d , NM = N o n m a i n t a i n e d . 104 Correlating catch with l a r v a l density A. Estimating l a r v a l densities The mean l a r v a l densities/plot estimated from lower branch beating were s i g n i f i c a n t l y correlated with the mean number of larvae/m 2 foliage/plot in the mid-crown in 1984 (r = 0.92; n = 9) and 1985 (r = 0.97; n = 10), and with the mean number of larvae/per 100 new shoots in 1984 (r = 0.85; n = 9) and 1985 (r = 0.93; n = 10)(Figs. 27, 28, Appendix IV). Beckwith (pers. comm.)1^ also found a good correlation between estimates of l a r v a l densities made by lower branch beating and mid-crown branch sampling. The mean number of larvae/three branches/plot were converted to the number of larvae/m 2 foliage/plot by assuming an average branch width of 30 cm and a length of 45 cm. These lower crown estimates were s i g n i f i c a n t l y lower than those in the mid-crown in both years (paired t-te s t s ; P ^ 0.05). Campbell et a_l. (1984) also found that western spruce budworm l a r v a l and pupal densities were lower in the lower crown than in the upper crown, but that average density in any crown stratum could be used to predict the average densities in other s t r a t a . Lower branch beating was therefore considered a r e l i a b l e method of estimating r e l a t i v e budworm populations, at least within the range of population densities sampled. It was also much faster u R.C. Beckwith, P a c i f i c Northwest Forest and Range Experiment Station, U.S.D.A., Forest Service, C o r v a l l i s , Oregon 97331. .105 and easier than pole-pruning, but unfortunately would be limited to r e l a t i v e l y open-grown trees. B. Trap catch vs l a r v a l density in the same generation Correlations between the mean t o t a l season's moth catch in 1984, based on one sample/plot of each trap system, and l a r v a l density in 1984, were not s i g n i f i c a n t for any of the eight trap systems (Table 43, Appendix IV). The common logarithmic (base 10) transformation of trap catch did not improve c o r r e l a t i o n s . Correlations between the mean t o t a l catch (n = 5 traps/plot in 5 plots) in non-maintained sticky traps and Uni-traps, both baited with 0.05% ALD, were much improved from those based on only one sample/plot but were also not s i g n i f i c a n t (Table 44, Appendix IV). However, when plot 12 was excluded from analysis the mean to t a l catch in the non-maintained Uni-traps was s i g n i f i c a n t l y correlated with the number of larvae/m2 foliage (r = 0.97; P ,^ 0.05), the number of larvae/100 new shoots (r = 0.95; P4 0.05), and the number of larvae/three branches (r = 0.94; P ^ 0.05); .i.e. about 90% of the variation in mean t o t a l catch in 1984 in plots 1, 2, 5, and 7 was due to v a r i a t i o n in l a r v a l density in the same generation (Fig. 18). Plot 12 was located at the lower end of the Oregon Jack Creek v a l l e y . I suspected that the very high r a t i o of trap catch to l a r v a l density in plot 12 was due to a large influx of moths which had dispersed from up-valley infestations and were carried into the plot on down-valley winds. Although I did not test t h i s d i r e c t l y , I excluded plot 12 from the plots trapped by 400 380 H 360 340 H 320 300 280 -260 -240 -220 200 UNI-TRAP. 0.05% NM y = 1.29x + 159 r - 0.97 ( - plot 12) • —T-20 40 T X 60 I 80 X X X X 100 120 NO. LARVAE/M 2 FOLIAGE/PLOT 1984 -1 r 140 - 1 — ~ x 160 180 F i g . 18. The mean t o t a l season's catch/plot in non-maintained (NM) Uni-traps (n = 5 traps/plot) vs the number of larvae/nr foliage/plot in the same generation. Regression was calculated by excluding plot 12, designated by the s o l i d square. o 1 07 Shepherd in 1985 and substituted a mid-valley plot instead. However, t o t a l season's catch in non-maintained Uni-traps, baited with 0.03% ALD instead of 0.05% ALD, was not s i g n i f i c a n t l y correlated with the 1985 densities of larvae/three branches (r = -0.19), larvae/m 2 foliage (r = -0.33) or larvae/100 new shoots (r = 0.24). The difference in correlations between 1984 and 1985 was probably not because of the s l i g h t change in pheromone concentration. It may have been due to a change in the r e l a t i v e budworm survival rates in the © d i f f e r e n t p l o t s . Regardless of the reasons for i t , the relat i o n s h i p between trap catch and l a r v a l density in the same generation was not consistent between di f f e r e n t locations or between years. The c o e f f i c i e n t s of determination for the regressions of trap catch (1984) vs l a r v a l density (1984) were s i g n i f i c a n t l y improved by including plot BA and plot FOL as additional independent variables, but only when plot 12 was excluded (Table 31 ) . C. Trap catch vs l a r v a l density in the following  generation Trap catches were better correlated with the following year's l a r v a l densities than with l a r v a l densities in the same generation. Correlations were s i g n i f i c a n t (P ^  0.10) between the number of larvae/three branches and the t o t a l catch in the maintained sticky traps baited with 0.05% ALD (r = 0.44)(Fig. 19) and the maintained Uni-traps baited with 0.05% ALD (r = Table 31. The e f f e c t of estimated p l o t basal area/ha and f o l i a g e biomass/ha on the r e l a t i o n s h i p between to t a l 1984 seasons catch in Uni-traps, b a i t e d with 0.05% ALD, (n = 1 trap/plot) and the mean number of larvae/three branches/plot in the same generation (beat 84). Analysis excluded p l o t 12 (n = 14). REGRESSION COEFFICIENT OF DETERMINATION ( r 2 ) 1 Catch i n maintained Uni-trap vs beat 1984 0. . 18 Catch in maintained Uni-trap vs beat 1984 + BA 0. .49 ** Catch 1n maintained Uni-trap vs beat 1984 + FOL 0. ,37 * Catch in nonma1ntained Uni-trap vs beat 1984 0. .03 Catch in nonmaintained Uni-trap vs beat 1984 + BA 0. ,40 * Catch i n nonmaintained Uni-trap vs beat 1984 + FOL 0. . 23 "'"Regression i s s i g n i f i c a n t , * J/^0.10, ** JP-^.0.05 MEAN NO. LARVAE/3 BRANCHES/PLOT 1985 6 0 1 110 0.44) (Fig. 20), and between the number of larvae/100 new shoots and t o t a l catch in the maintained sticky trap baited with 0.05% ALD (r = 0.55)(Fig. 21). Catch in the non-maintained Unitrap was not s i g n i f i c a n t l y correlated with any estimate of l a r v a l density (Table 45, Appendix IV). The cor r e l a t i o n between catch in the non-maintained Uni-trap, baited with 0.05% ALD, and the number of larvae/three branches was improved by r e p l i c a t i n g the traps f i v e / p l o t (r = 0.52) but was not s t a t i s t i c a l l y s i g n i f i c a n t due to the smaller number of plots sampled (Table 46, Appendix IV). Most correlations were improved when plot 12 was excluded from the analysis; catch in the maintained Uni-trap, baited with 0.05% ALD, was s i g n i f i c a n t l y correlated with the number of larvae/three branches (r = 0.67, P ^  0.05)(Fig. 20), the number of larvae/m 2 foliage (r = 0.58, 0.10), and the number of larvae/100 new shoots (r = 0.75, P ^ 0.05). The co r r e l a t i o n c o e f f i c i e n t s were not improved by the common logarithmic transformation of trap catch. The s i g n i f i c a n t negative c o r r e l a t i o n (r = -0.47) found between catch in the non-maintained sticky trap, baited with 0.05% ALD, and the number of larvae/three branches is puzzling. Zero c o r r e l a t i o n was expected because the sticky traps should have saturated at about 100 moths/trap. When these non-maintained sticky traps were replicated 5 times/plot the mean t o t a l catch was not negatively correlated with l a r v a l density (Table 46, Appendix IV). 22 -20 - UNI-TRAP, 0.05% M 18 - • 16 - y = 1.38 + 0.014x • 14 - r = 0.67 ( - plot 12) 12 -• • 10 -a -• • • 6 - • 4 -2 -n • U i i 1 i I 1 1 1 0.1 0.3 0.5 0.7 0.9 (Thousands) CATCH/PLOT 1984 (n = 1 trap/plot) F i g . 20. The mean number of larvae/three branches/plot in 1985 vs the t o t a l 1984 season's catch/plot in maintained Uni-traps, baited with 0.05% ALD. Regression was calculated excluding plot 12, designated by the s o l i d square. F i g . 21. The mean number of larvae/100 new shoots/plot in 1985 vs the t o t a l season's catch in maintained sticky traps (M), baited with 0.05% ALD. h-1 \ IS3 1 13 The maintained Uni-trap, and the maintained sticky trap, baited with 0.05% ALD, had the closest p o s i t i v e c o r r e l a t i o n of to t a l catch with the following year's l a r v a l density of a l l trap systems tested. The Uni-trap was superior to the sticky trap when plot 12 was excluded (Table 45, Appendix IV). The c o e f f i c i e n t s of determination for the regressions of l a r v a l density in 1985 vs t o t a l catch in 1984 were s i g n i f i c a n t l y , improved by the addition of plot BA and plot FOL as independent variables, but again, only when plot 12 was excluded (Table 32). Table 32. The e f f e c t of estimated p l o t basal area/ha and f o l i a g e biomass/ha on the r e l a t i o n s h i p between total 1984 seasons catch in Uni-traps, b a i t e d with 0.05% ALD, (n = 1 trap/plot) and the mean number of larvae/three branches/plot the following year (beat 85). Analysis excluded p l o t 12 (n = 14). REGRESSION COEFFICIENT OF DETERMINATION ( r 2 ) Beat 1985 vs Catch in maintained Uni -trap 0. .45 * * Beat 1985 vs Catch in maintained Uni -trap + BA 0. 72 * * * Beat 1985 vs Catch in maintained Uni -trap + FOL 0. 71 * * * Beat 1985 vs Catch 1n nonmaintained Uni-trap 0. 11 Beat 1985 vs Catch i n nonmalntained Uni-trap + BA 0. 31 Beat 1985 vs Catch in nonmaintained Uni-trap + FOL 0. 38 * 1 Regression i s s i g n i f i c a n t , * p<0.10, ** p ^0.05, * * * p ^0.01. 115 DISCUSSION PHEROMONE-MEDIATED BEHAVIOR Electrophysiological responses The male moth's antenna responded to AC and OH but the threshold concentration was two orders of magnitude higher than that for ALD. The amplitude and lag in response to binary or ternary blends of 0.05% ALD and 0.5% AC or 0.5% OH were not s i g n i f i c a n t l y greater than those in response to 0.05% ALD alone, which suggests that the three components have common receptor s i t e s on the s e n s i l l a e . Seabrook (1977) conducted cross-adaptation experiments with male spruce budworm moths and concluded that E- and Z- ALD, and E- AC were detected by common receptor s i t e s . An understanding of the way in which the male western spruce budworm moth detects and codes for a s p e c i f i c pheromone blend would require further experimentation using recordings from single s e n s i l l a e . The antennae of wild males recovered sooner following ALD stimulation than did those of laboratory males. The l a t t e r were also less responsive to 0.05% AC. Possible reasons for these differences in s e n s i t i v i t y were a sublethal i n f e c t i o n of Nosema in the laboratory colony, and genetic differences between the populations. These w i l l be discussed further. 1 16 Behavioral response vs ALD concentration The percentage response of male moths in the wind tunnel support R o e l o f s (1978) threshold hypothesis. Percentage upwind f l i g h t to the ALD lure appeared to be activated between concentrations of 0.0005% and 0.005% but i t dropped off above 0.05% (Tables 1-3). I expect that d i s o r i e n t a t i o n of the male moth in the wind tunnel would be even greater in response to concentrations above 0.5% ALD but t h i s was not tested. The onset of wingfanning in laboratory males, and take-off in a l l three populations, was s i g n i f i c a n t l y delayed when the ALD concentration was decreased (Table 4-6). Carde and Hagaman (1979) obtained similar results with the gypsy moth and suggested that the male i n i t i a t e s wing-fanning when i t s CNS can distinguish a neuronal f i r i n g rate from background noise; t h i s integration would require a longer period of stimulation at low than at high dosages. However, Linn and Gaston (1981a), working with the cabbage looper, found no change in the time from release to wing-fanning when they changed the pheromone concentration or blend. An inverse re l a t i o n s h i p between net upwind ground speed and pheromone concentration has been shown in the gypsy moth (Carde and Hagaman 1979), the Oriental f r u i t moth (Kuenen and Baker 1982a), and in the spruce budworm (Sanders et a l . 1981). This trend was evident in the western spruce budworm laboratory males, at 2-1 m from the lure, but was less apparent in the wild males and was lacking in the lab-wild males. Linn and Gaston 1 1 7 (1981a) observed no change in upwind f l i g h t speed of adult male cabbage loopers associated with pheromone concentration. Carde' and Hagaman (1979) suggested that increasing pheromone concentration could be used by the male moth to gauge the proximity of the c a l l i n g female. As the moth nears the lure the plume narrows and mean concentration across the plume increases. The male responds by reducing i t s ground speed and eventually arresting f l i g h t . A decrease in ground speed nearer the lure was observed in a l l three populations of the budworm and i s consistent with wind tunnel studies of the spruce budworm (Sanders 1986b) and the Indianmeal moth (Marsh et a l . 1978), and with f i e l d studies of the Egyptian cotton leafworm (Murlis et a l . 1982). Baker (1986) reviewed the current understanding of how moths orient to distant pheromone sources. The most accepted theory states that detection of pheromone by the moth i n i t i a t e s two behavioral programmes: s e l f - s t e e r i n g counterturning or regular zigzagging f l i g h t , and upwind anemotaxis. The Oriental f r u i t moth gauges i t s upwind progress by optomotor input and regulates i t s speed by maintaining a preferred image vel o c i t y (Kuenen and Baker 1982a). As pheromone concentration increases the optomotor response i s modified and the moth makes narrower and more frequent counterturns and eventually increases the angle of counterturns to 90° r e l a t i v e to a 0° wind axis, which arrests upwind progress (Kuenen and Baker 1982b). Sanders(1986b) suggested that pheromone concentration may be 118 used to regulate upwind ground speed instead of or in addition to optomotor input. It i s not clear why the relationship between f l i g h t speed and pheromone concentration was inconsistent in the d i f f e r e n t budworm populations. It i s possible that a trend was obscured by a l o t of variation in individual male's f l i g h t speed and a r e l a t i v e l y small number of replicates per treatment. A high degree of v a r i a b i l i t y in moth f l i g h t speed has been noted by others (Murlis et a_l. 1982; Marsh et a l . 1978; Carde'and Hagaman 1979). Carde' and Hagaman (1979) suggested that t h i s phenotypic variation evolved because of r e l a t i v e advantages of slow and fast f l i e r s ; under stable plume conditions a fast male would stand a better chance of f i r s t reaching a c a l l i n g female but in an unstable, meandering plume, a slow f l i e r might be more l i k e l y to track the plume and locate the female. The roles of minor components The effect of the minor components, AC and OH, alone or together, on the male moth's behavior appears to depend on the component ra t i o and release rate, the population of budworm observed and the distance of the moth from the lure. Despite variation in response between populations, the data suggest that the minor components in combination with the major component, ALD, s i g n i f i c a n t l y affected the orientation and pre-mating behavior of male moths. As in the case of the major component, there also appeared to be an optimum concentration for the minor 119 components. When added to 0.05% A L D , 0.005% OH s i g n i f i c a n t l y increased percentage copulatory attempts, 0.05% OH had l i t t l e e f f e c t , and 0.5% OH s i g n i f i c a n t l y reduced percentage locking on in wild moths and percentage wingfanning in lab-wild moths. The AC lures had l i t t l e e f fect when added to 0.05% A L D at concentrations of 0.005% but increased the percentage response of males when added at concentrations of 0 . 0 5 to 0.5%. The blend of ALD+AC+OH which was estimated to resemble that released from a v i r g i n female (0.05% A L D + 0.05% A C ) e l i c i t e d similar responses to those of the l a t t e r and s i g n i f i c a n t l y greater upwind f l i g h t , landing at the lure, and copulatory attempts, than did the 0.05% ALD lure. Sanders et a l . (1981) found that the net upwind ground speed of C . fumiferana male moths was s i g n i f i c a n t l y faster in response to two v i r g i n females than to pvc lures releasing 96/4 E/Z11-tetradecenal at about the same rate, and suggested that additional minor components in the female e f f l u v i a were possibly responsible. My data support a similar hypothesis for the western spruce budworm. The ground speed of lab-wild males in response to 0.05% ALD was s i g n i f i c a n t l y lower than that in response to the v i r g i n females, and was s i g n i f i c a n t l y increased by the addition of 0.05% AC or 0.05% AC + 0.05% OH (Table 2 0 ) . Generally speaking, the differences in percentage response between treatments became more pronounced as the distance of the male from the pheromone decreased. In other words, blends were more ea s i l y separated on the basis of close range behavior than 1 20 long range behavior. However, i t was apparent that long range behaviors were also affected by the minor components. The addition of 0.05% AC + 0.05% OH to 0.05% ALD increased the percentage upwind f l i g h t of lab-wild males at distances greater than 1 m from the lure. Variation in response There was much v a r i a b i l i t y in response to the pheromone blends, both within and between the budworm populations tested. Some males were non-responders and f a i l e d even to wing fan when exposed to ALD concentrations as high as 0.05% whereas others completed the entire sequence of behaviors in response to only 0.0005% ALD. This sort of variation was also seen in antennal s e n s i t i v i t y to pheromone as measured on the EAG. Some males produced an EAG response to very low concentrations of ALD while others did not. Considerable v a r i a b i l i t y in pheromone release rates and component ra t i o s has been observed in v i r g i n females of C. fumiferana (Morse et. a_l. 1982), C. occidentalis (Silk et a l . 1982), and other moth species (Barrer et a l . 1 987; Haynes et. a l . 1984; Pope et a l . 1982). This may have been partly responsible for the va r i a t i o n in percentage response to the v i r g i n females in d i f f e r e n t experiments e.£. 85% of lab-wild males locked-on and landed at the v i r g i n female in one of the experiments comparing ALD,AC, and OH (Table 15), but only 4.6% did so in the experiment comparing ALD concentrations (Table 3). 121 The behavior of males from the laboratory colony was less affected by the addition of minor components than that of the wild or lab-wild males. The reasons for this are unclear but i t may have been due to a low l e v e l Nosema in f e c t i o n , or to genetic d r i f t in the r e l a t i v e l y isolated and inbred laboratory colony. A sample of 13 laboratory males which had been flown in the bioassay comparing blends of ALD, AC and OH, were l a t e r found to contain a mean of 7.4 m i l l i o n Nosema spores/mg abdomen tis s u e . It i s possible that the infecti o n affected the a b i l i t y of the males to discriminate between pheromone blends. Sublethal i n f e c t i o n l e v e l s of 2-20 m i l l i o n Nosema spores/mg have been negatively correlated with the percentage of western spruce budworm male moths wing-fanning, taking-off and f l y i n g upwind to a 0.05% ALD lure (Sweeney and McLean 1987). Many generations of inbreeding in laboratory populations may lead to differences in genetic make-up and genetic homozygosity, which in turn could produce differences in vigor, disease resistance and behavior (Boiler 1972; Huettel 1976). The laboratory colony was i n i t i a l l y put through a bottleneck by selecting budworms which did not undergo diapause and i t had been bred for more than 100 generations. Certainly there i s l i t t l e selection pressure for long distance orientation of the adult male budworm to the c a l l i n g female in the laboratory environment since mating takes place inside a small paper bag. Liebhold and Volney (1984b) found that v i r g i n females from a laboratory colony of C. occidentalis no longer r e s t r i c t e d pheromone emission to the circadian rhythm noted in their wild 122 c o u n t e r p a r t s ; t h e y s u g g e s t e d t h a t t h e c i r c a d i a n r h y t h m h a d been l o s t due t o a l a c k o f s e l e c t i o n p r e s s u r e o v e r s e v e r a l g e n e r a t i o n s o f m a t i n g i n t h e d a r k i n t h e l a b o r a t o r y . M i n k s ( 1 9 7 1 ) f o u n d t h a t f e m a l e s o f an i n - b r e d l a b o r a t o r y s t r a i n o f t h e s u m m e r f r u i t t o r t r i x moth, A d o x o p h y e s o r a n a ( F . v . R . ) , p r o d u c e d l e s s pheromone t h a n t h o s e f r o m a more r e c e n t l y e s t a b l i s h e d c o l o n y . F l e t c h e r e t a l . ( 1 9 6 8 ) n o t e d t h a t r e s p o n s e o f f e m a l e screwworm f l i e s , C o c h l i o m y i a h o m i n i v o r a x ( C o c q u e r e l ) , t o m a l e pheromone was g r e a t e r i n an i n - b r e d l a b o r a t o r y s t r a i n t h a n i n a w i l d p o p u l a t i o n a n d a t t r i b u t e d t h i s t o a r t i f i c i a l s e l e c t i o n p r e s s u r e s i n t h e l a b o r a t o r y e n v i r o n m e n t . H owever, Sower e t a l . ( 1 9 7 3 ) f o u n d no d i f f e r e n c e s b e t w e e n l a b o r a t o r y a n d w i l d s t r a i n s o f t h e a l m o n d moth, C a d r a c a u t e l l a ( W a l k e r ) , i n t e r m s o f pheromone p r o d u c t i o n and b e h a v i o r a l r e s p o n s e s t o pheromone. S t o c k and R o b e r t s o n (1982) f o u n d r e d u c e d h e t e r o z y g o s i t y i n t h e 8 8 t h g e n e r a t i o n o f t h e B e r k e l e y n o n - d i a p a u s i n g c o l o n y o f C. o c c i d e n t a l i s when c o m p a r e d w i t h w i l d budworms b u t d i d n o t o b s e r v e s i g n i f i c a n t r e d u c t i o n s i n v i g o r , l o n g e v i t y , o r d i s e a s e r e s i s t a n c e . V a r i a t i o n i n pheromone b l e n d may a l s o o c c u r b e tween w i l d p o p u l a t i o n s . The w e s t e r n s p r u c e budworm has a v e r y b r o a d r a n g e , f r o m B r i t i s h C o l u m b i a t h r o u g h t o New M e x i c o , and due t o t h e c o m p l e x t e r r a i n , p o p u l a t i o n s a r e o f t e n s c a t t e r e d i n s e m i -i s o l a t e d i s l a n d s , w h i c h l e a d s t o g e n e t i c d i v e r g e n c e ( P o w e l l 1 9 8 0 ) . S t o c k a n d C a s t r o v i l l o ( 1 9 8 1) c o m p a r e d i s o z y m e s o f f i v e C h o r i s t o n e u r a s p e c i e s and f o u n d a s much i n t r a s p e c i f i c v a r i a t i o n a s i n t e r s p e c i f i c v a r i a t i o n . W i t h t h e a p p a r e n t l y w i d e v a r i a t i o n 123 between individuals, there i s ample opportunity for selection to produce differences in the r e l a t i v e r a t i o of components in the female e f f l u v i a and in the optimum blend for male response. Another difference between the populations which might explain some of the var i a t i o n in their behavior is the difference in rearing regimes. The wild budworms developed naturally in the f i e l d up to the fourth or f i f t h instar and were subsequently reared to pupation in conditions similar to those for the laboratory and lab-wild males except that the li g h t i n t e n s i t y was lower for the wild larvae. F i e l d bioassays In contrast to many of the wind tunnel bioassays, the trapping bioassays showed very few s i g n i f i c a n t differences between various blends of ALD, AC, and OH, so long as ALD was included in the blend. It may be simply that the wind tunnel bioassays, because they allow close range observations, are superior to f i e l d trapping bioassays for detecting possible e f f e c t s of secondary components on the male's behavior. Another p o s s i b i l i t y i s that trap saturation limited the catch in the more a t t r a c t i v e blends and obscured differences between blends. I made an e f f o r t to replace traps before appreciable saturation could occur but mean catches of about 50 moths/trap were recorded in three of eight blend comparisons. Future trapping bioassays should be done with high-capacity traps. Using Uni-124 traps, Shepherd (pers. comm.)11 found that adding 0.001% AC to 0.03% ALD s i g n i f i c a n t l y increased the catch of western spruce budworm males in the f i e l d . The fact that traps baited with v i r g i n females caught fewer than those baited with 0.05% ALD, or blends containing ALD, c o n f l i c t s with the wind tunnel observations and was surprising since release rates should have been comparable. However, others have shown that catches of male moths in triangular sticky traps baited with synthetic lures, at release rates about that of a v i r g i n female, are s i g n i f i c a n t l y greater than the catches in traps baited with v i r g i n females (Choristoneura orae (Gray et a l . 1984a); C. retiniana (Daterman et a l . 1984); Rhyacionia buoliana (Gray et a l . 1984b)). It i s possible that fluctuations in temperature in the f i e l d resulted in higher net release rates than those measured under controlled laboratory conditions. Moreover, v i r g i n females in the sticky traps were sometimes found caught in adhesive which had oozed through the fibreglass cage. This probably i n h i b i t e d c a l l i n g of the female and possibly accounts p a r t i a l l y for the poor catches. It i s also possible that c a l l i n g by the v i r g i n female was adversely affected by the odor of the adhesive or by stimuli from captured males. 1 1 R. F. Shepherd, P a c i f i c Forestry Centre, 506 W. Burnside Road, V i c t o r i a , B.C. 1 25 MONITORING WITH PHEROMONE TRAPS Factors a f f e c t i n g trap catches A. Height and proximity to foliage The higher catches in traps hung in trees as compared with those in traps hung in the open, were to be expected because large numbers of moths were often seen f l y i n g near the crowns of host trees. Moth a c t i v i t y was especially noticeable in the upper crown l e v e l s , coinciding with s i g n i f i c a n t l y greater trap catches there compared with catches in traps hung 1.5-2 m above the ground. The phenomenon of male moths concentrating their f l i g h t around host trees has been observed previously in the western spruce budworm (Liebhold and Volney 1984a; Sower and Daterman 1985) and also in the spruce budworm (Greenbank et a l . 1980), the larch casebearer (Witzgall and Priesner 1984) and the gypsy moth (Richerson et. a l . 1976; Carde' and Hagaman 1984). When I f i r s t observed t h i s behavior I assumed that the male moths were orienting to c a l l i n g females on host foliage and that female density was higher in the upper crown than in the lower crown. The l a t t e r assumption was based on previous findings of greater egg, l a r v a l ( L 4 ) , and pupal densities in the mid- and upper-crown leve l s (Campbell e_t a l . 1984; Carolin and Coulter 1972) coupled with evidence that females usually mate and lay 50% of their eggs before dispersing (Outram 1971; Sanders and Lucuik 1972, 1975; Wellington and Henson 1947; Wellington 1948). However, Liebhold and Volney (1984a) found that foliage 1 26 proximity increased the catch of budworm when the population (and therefore female density) was low, and also when traps were hung in non-host trees, and they suggested that the male moths were orienting to a v i s u a l stimulus rather than an olfactory one. Sower and Daterman (1985) observed male western spruce budworm moths f l y i n g near host foliage and also concluded that the moths were orienting to the v i s u a l stimulus of tree crowns rather than to c a l l i n g females; they speculated that t h i s behavior was either controlled by a circadian rhythm or was activated by diffuse pheromone. Gypsy moth males also orient to trees and other v e r t i c a l silhouettes (Carde' and Hagaman 1 984; Elkinton and Carde' 1983; Richerson et a l . 1976; Richerson 1977). Richerson et a l . (1976) stated that t h i s tree-oriented searching a c t i v i t y was stimulated by sex pheromone whereas Elkinton and Carde' (1983) suggested that pheromone stimulation was unnecessary. The increased trap catch in the upper crown might be due to the more prominent vis u a l silhouette at t h i s height. Although trap catch was s i g n i f i c a n t l y increased in the upper crown, the c o e f f i c i e n t of variation of catch was not d i f f e r e n t between crown l e v e l s . This c o n f l i c t s with M i l l e r and McDougall (1973) who found a lower inter-trap variance of spruce budworm catch in the upper canopy than in the lower canopy. Therefore, although they were less sensitive, traps placed at 1.5-2 m would probably provide as good a r e l a t i v e index of male moth numbers as those in the upper crown, and they are easier to use. 127 Contrary to one of my hypotheses, the c o e f f i c i e n t of variation of catch/trap was much higher in traps in the open than in traps in trees. I had expected that the more uniform immediate surroundings of the open traps would reduce v a r i a b i l i t y in catch. Besides producing less v a r i a t i o n in catch, hanging traps from trees i s usually more convenient than using tripods or poles. An exception would be when trapping was desired in very open stands ( F e l l i n and Hengel 1983). These data and those of others (Liebhold and Volney 1984a; Sower and Daterman 1985) suggest that a large percentage of male western spruce budworm moths locate females by f l y i n g near the crowns of host trees. This begs the question: how important is long-distance pheromone-mediated orientation in the successful location of a female by a male moth, and does i t vary with population density? Sanders and Lucuik (1972) argued that, in high populations, male spruce budworm moths can locate and mate with females before the l a t t e r have begun c a l l i n g , and they suggested that the males would use d i f f e r e n t mate-location strategies at d i f f e r e n t population dens i t i e s . At high densities the males "buzz" near host foliage and locate the female by close-range pheromone cues; at low densities, the males would orient upwind along a pheromone plume. Carde' and Hagaman (1984) suggested a similar phenomenon for the gypsy moth; in dense populations, many females are mated before they start c a l l i n g , so selective pressure to release pheromone is relaxed. If this is true for the western spruce budworm, i t introduces another source of v a r i a b i l i t y when studying the male moth's pheromone-128 mediated behavior. Wild moths c o l l e c t e d from a population which has remained at a low density for a number of generations might hypothetically show a greater percentage of locking-on and upwind f l i g h t at long-distances than would moths from a high density population. This hypothesis remains to be tested. B. Interference A l a t i n square design was used in the 1982 f i e l d comparisons of trap designs in order to remove variation in catch due to a trap's position within the p l o t . Analysis of variance showed that the l a t i n square design was not required in either experiment. However, there was a s i g n i f i c a n t column ef f e c t in the second experiment; the t o t a l catch per column of four traps was greatest in the up-valley column (1439) and successively decreased in each down-valley column (995,827,543). This suggests that trap interference may have occurred between traps along the same wind l i n e . Wall and Perry (1978) found that upwind pheromone traps caught s i g n i f i c a n t l y more pea moth males (Cydia nigricana (F.)) than did central or downwind traps and they suggested that this was due to the overlap of pheromone plumes between the traps. Evidence of trap interference has also been noted in the captures of C. fumiferana in traps spaced less than 40 m apart (Houseweart et a_l. 1981). However, i f interference was occurring between traps, why was i t suggested in the second experiment but not in the f i r s t ? An alternate p o s s i b i l i t y i s that moths from up-valley infestations were car r i e d into the experimental plot on down-1 29 valley winds and encountered the upwind traps f i r s t . The dramatic increase in trap catch during the second experiment may be evidence of such d i s p e r s a l . In most of the trapping bioassays af t e r 1982, treatments were set out in a single l i n e judged to be perpendicular to the prevailing winds in order to reduce interference between traps. C. Ef f ic iency E f f i c i e n c y of the sticky trap decreased abruptly with a catch of only 10 males. The sticky traps saturated even when they were baited with 0.0005% ALD; the mean cumulative season's catch was s i g n i f i c a n t l y increased when the traps were maintained (paired t - t e s t ; 0.001). This difference might have been greater i f the maintained traps had been replaced with a fresh sticky trap every two days. When less than 10 moths were in the trap, as was frequently the case with 0.0005% ALD, the moths were removed with a stick rather than replacing the entire trap. The e f f i c i e n c y of the cleaned traps was probably less than that of a fresh trap due to accumulation of wing scales (Shepherd 1979) and loss of stickiness with age (Houseweart et a l . 1981). These results indicate that the sticky trap i s unsuitable for monitoring a wide range of population densities. Cumulative catch also affected the e f f i c i e n c y of the Uni-trap. The mean t o t a l season's catch in Uni-traps, baited with 0.05% ALD, was s i g n i f i c a n t l y increased when moths were removed 130 from the traps every two days (paired t - t e s t ; 0.001). Others have observed decreased e f f i c i e n c y associated with large catches in high-capacity traps and have suggested that moths were being repelled by v o l a t i l e s from the dead moths in the trap (Sanders 1986c; Shepherd 1985a; Struble 1983). Sanders (1986c) concluded that t h i s repellency was not affected by the number of dead moths in the trap or by the length of time they had been in the trap, and that the e f f i c i e n c y of the non-maintained Uni-trap would therefore be r e l a t i v e l y consistent over the duration of the f l i g h t season. However, my results suggest that the l a t t e r may not hold true for catches of western spruce budworm moths. Total catch in the non-maintained Uni-trap dropped off r e l a t i v e to that in the maintained Uni-trap in plots with high catches. Although the c o r r e l a t i o n c o e f f i c i e n t s are not s i g n i f i c a n t l y d i f f e r e n t ( t - t e s t with Fisher z_ transformation, P^0.05; Zar 1984), a nonlinear equation f i t s the data better ( r 2 = 0.73) than the linear one ( r 2 = 0.66)(Fig. 22). Moreover, maintenance had no effect on the t o t a l season's catch in Uni-traps baited with 0.0005% ALD. These results suggest that the repellent ef f e c t i s related to the number of moths caught rather than the length of time the moths were in the trap. Allen et a l . (1986) also found evidence of decreased e f f i c i e n c y of high-capacity, covered funnel traps with increased catches of spruce budworm, and suggested that the r e l a t i o n s h i p between catch and l a r v a l density might be distorted in high populations. Despite the effects of cumulative catch on the non-maintained Uni-trap, i t s t i l l remained much more consistent 500 450 400 -350 -300 -250 -200 -150 -100 0.3 i r 0.5 0.7 (Thousands) TOTAL CATCH/PLOT IN UNI-TRAP 0.05% M Fig. 22. Plot showing the effect of cumulative catch on the e f f i c i e n c y of the Uni-trap. Cumulative catch in the non-maintained Uni-trap dropped off r e l a t i v e to the maintained Uni-trap. A c u r v i l i n e a r model (r 2= 0.73) f i t s the data better than the linear model (r a= 0.66). 132 throughout the trapping season than did the non-maintained- or maintained sticky trap. When t o t a l season's catches in the sticky traps, baited with 0.05% ALD, were plotted against those of the maintained Uni-trap, the r e l a t i v e e f f i c i e n c y of the sticky traps dropped off in plots with high cumulative catches, even when the traps were cleaned every two days (Fig. 23). Non-maintained sticky traps baited with 0.05% ALD saturated at about 100 moths/trap. The Uni-trap, baited with 0.05% ALD, and with dichlorvos in the c o l l e c t i n g j a r, i s therefore considered the best trap-lure combination, of those tested here, for monitoring the western spruce budworm because i t was more consistent than the sticky trap under non-maintained conditions and was sensitive enough to capture moths in plots with low l a r v a l d e n s i t i e s . It had a lower c o e f f i c i e n t of v a r i a t i o n of trapping e f f i c i e n c y than the Multi-Pher trap, and i s more durable than the sticky trap, so i t could probably be used for several trapping seasons. Predicting population trends Correlations between trap catch and l a r v a l density in the same generation were very poor in 1984 and 1985. V a r i a b i l i t y in trap catch was probably partly to blame because correlations were improved when traps were replicated at f i v e / p l o t . The mean catch in five non-maintained Uni-traps/plot was not s i g n i f i c a n t l y correlated with the catch in one trap/plot (r = 0.15). The mean c o e f f i c i e n t of v a r i a t i o n for the mean t o t a l 1 0.9 -• 0.2 - STICKY 0.05% + NONMAINTAINED 0.1 - ±± .f + ( + ^± ± ± ^_ 0 H 1 1 1 1 1 1 1 1 1 0 0.2 0.4 0.6 0.8 1 (Thousands) TOTAL CATCH/PLOT IN UNI-TRAP 0.05% M F i g . 23. Plot showing cumulative catch in maintained and non-maintained sticky traps, r e l a t i v e to cumulative catch in the maintained Uni-trap. A l l traps were baited with 0.05% ALD. Even when maintained, catch in the sticky trap dropped off r e l a t i v e to the Uni-trap at higher cumulative catches. 1 34 catch in non-maintained Uni-traps (n = 5/plot) was 34% in 1984 and 1985. Ten Uni-traps are required per plot to estimate mean trap catch with an allowable error of 30% (with 95% confidence) according to the formula (Husch et a l . 1972): n = t.2. CV?. (AE%) 2 where n = number of traps required per plot, t = value of t d i s t r i b u t i o n at 95% confidence ( 2-tailed test and 4 degrees of freedom), CV = c o e f f i c i e n t of var i a t i o n of mean catch (n = 5), and AE% = allowable error as a percent of the mean. The same formula shows that one trap/plot and five traps/plot estimate trap catch with about 95% and 42% error respectively. This suggests that future attempts to monitor budworm populations with Uni-traps should use the mean t o t a l catch of at least five to ten traps/plot. However, even when traps were replicated f i v e / p l o t , the cor r e l a t i o n between mean t o t a l catch in non-maintained Uni-traps and l a r v a l density in the same generation was s i g n i f i c a n t only in 1984, and then only when plot 12 was excluded from the analysis. Correlations were better between trap catch and l a r v a l density in the following generation but even then, the cor r e l a t i o n between t o t a l catch in 1984 in the maintained Uni-trap accounted for only 19% ( r 2 ) of the variation in 1985 l a r v a l density (45% when plot 12 was excluded). There are obviously 1 35 several factors influencing l a r v a l density besides the preceding year's adult population, as estimated by trap catch. A good c o r r e l a t i o n between trap catch and l a r v a l density, in either the same or following generation, requires a r e l a t i v e l y uniform r a t i o of trap catch to l a r v a l density in a l l pl o t s . However, t h i s r a t i o was much greater in plots 11,12,14, and 15 than in the other plots (Fig. 24). The r a t i o should perhaps have been even higher in plots 12-15 because the traps were apparently set out after some moths had already flown, according to the seasonal trap catch p r o f i l e s (Figs. 29-36, Appendix IV). Several possible factors might contribute to the difference in the r a t i o of trap catch to l a r v a l density between di f f e r e n t p l o t s . These include errors in l a r v a l or adult sampling, differences in stand structure, net immigration of dispersing male moths into some plots but not others, differences in budworm survival rates, and differences in competition for male moths between pheromone traps and v i r g i n females (Daterman 1979; Allen et a l . 1986). These were not tested as hypotheses but the pr o b a b i l i t y of their occurrence is speculated upon below. The time of sampling for the f i f t h and sixth instar larvae is important because these stages are heavily preyed on by birds and ants (Campbell and Torgersen 1982; Campbell et a l . 1983a). Most plots were sampled in order of increasing elevation in an ef f o r t to sample the larvae at the same stage of development in each pl o t . However, the larvae in plots 11 and 12 were sampled 1 3 6 4.5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 i 2 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 PLOT NO. F i g . 24. The var i a t i o n between plots in the r a t i o of trap catch/larval density (log y). A. The t o t a l 1984 season's catch/plot in maintained Uni-traps over the mean number of larvae/three branches/plot in 1984. B. The t o t a l 1984 season's catch/plot in maintained Uni-traps over the mean number of larvae/three branches/plot in 1985. Plots 11, 12 were located in the lower end of the Oregon Jack Creek valley while plots 14 and 15 were located in the upper end. 137 r e l a t i v e l y late in 1984 and th e i r densities may therefore have been underestimated due to increased exposure to predators and other factors. Plots 11 and 12 were not sampled late in 1985, however, but they s t i l l had low l a r v a l d e n s i t i e s . A given number of larvae/m 2 foliage may not represent the same number of larvae/ha in d i f f e r e n t plots due to differences in stand density and foliage biomass/ha between p l o t s . By including plot basal area as an additional independent variable, Allen et a_l. (1986) s i g n i f i c a n t l y improved the c o e f f i c i e n t of determination of l a r v a l density vs the preceding year's catch of spruce budworm in 5 of 26 cases. Estimates of plot BA and plot FOL s i g n i f i c a n t l y improved the c o e f f i c i e n t s of determination for trap catch vs l a r v a l density in the same- and the following generations, but only when plot 12 was excluded (Tables 31, 32). These estimates of basal area and foliage biomass were based on only two to four prism plots/sample plot and are therefore not very precise but they suggest that stand structure a f f e c t s the relationship between trap catch and l a r v a l density. In the Oregon Jack Creek valley and others l i k e i t , winds tend to flow both up- and across-valley during the afternoon and down-slope and down-valley after sunset. These winds provide currents in which dispersing insects can t r a v e l (Wellington 1979). Shepherd (1979) observed that f l i g h t of western spruce budworm peaked after sunset and proposed that the net dispersal of moths would be downwind into the lower elevation p l o t s . I observed that peak response to pheromone traps occurred about 2 138 h before to 2 h after sunset and I suggest that i t is possible that dispersing moths were ca r r i e d downwind in both up-valley and down-valley d i r e c t i o n s . If such dispersal occurred, and was density dependent, then the low density plots located in the upper valley (plot's 14 and 15) and lower valley extremes (plot's 11 and 12) would have been subject to a net immigration of moths. The observation of large numbers of budworm moths f l y i n g under the street l i g h t s of Ashcroft was evidence that down-valley dispersal occurred. The land immediately surrounding the town i s non-forested, so the moths were probably c a r r i e d into the town on down-valley and down-slope winds from infestations in the surrounding h i l l s . I also observed nighthawks a c t i v e l y f l y i n g and diving above the forest canopy around sunset on several evenings and I assumed they were feeding on budworm moths and other insects f l y i n g above the canopy (Wellington 1979). Comparatively l i t t l e i s documented on the dispersal behavior of the western spruce budworm but a very extensive study has been conducted on the dispersal of the spruce budworm in New Brunswick (Greenbank et a l . 1980). Apparently, spruce budworm moths in moderate to heavy infestations f l y up and out of the forest canopy each night and are carried downwind for considerable distances. Sixty to eighty percent of the dispersing moths are females carrying about 50% of their eggs (Greenbank et a_l. 1980). There i s also some evidence that dispersal is density dependent, occurring mainly in areas of heavy d e f o l i a t i o n (Sanders 1985). Campbell et a l . (1983b) found 1 39 egg densities of the western spruce budworm to be often much greater than expected from the previous year's resident female population, and suggested that egg-carrying females had immigrated into areas of low population. If the plots in the valley extremes were acting as sinks for dispersing moths, i t would account for the high trap catches in these plots despite low densities of larvae in the same generation. However, i f 60-80% of the immigrating moths were egg-carrying females, as estimated for C. fumiferana, then the l a r v a l densities in plots 11,12,14 and 15 should have increased proportionately the following year, but they did not. It i s possible that egg carrying females immigrated into the valley extremes but that survival from the egg to the late l a r v a l instars was much lower in these plots than at mid-elevations-. Unfortunately, I did not estimate egg mass densities or mortality rates in any of the p l o t s . However, there i s evidence from the l i t e r a t u r e that budworm survival i s reduced above and below certain elevations. This is hypothesized to be primarily due to poor synchronization of l a r v a l emergence with bud flush in the spring (Shepherd 1985b). The survival rate i s thought to be at i t s highest for larvae that emerge from hibernacula when the buds are swollen and easy to penetrate (Blais 1957). The buds conceal the larvae from predators and also act as a natural greenhouse, keeping the larvae warmer than the surrounding a i r temperature (Wellington 1948). Larvae which emerge before bud swell must mine old needles, and those which emerge late r e l a t i v e to bud flush are exposed to predators for a r e l a t i v e l y 140 longer period (Shepherd 1985b). Thus, some of the variation in the following year's l a r v a l density i s probably due to d i f f e r e n t i a l survival between locations up- and down-valley. Of course, budworm survival would vary not only between locations but between years in the same location, depending on a number of factors including weather. The lower ratios of trap catch to l a r v a l density in the plots with high l a r v a l populations could also be due to competition between the pheromone traps and v i r g i n female moths. A fixed density of pheromone traps should t h e o r e t i c a l l y capture a greater proportion of males in a stand with fewer c a l l i n g females, due to less competition (Carde 1979). M i l l e r and McDougall (1973) found that the r a t i o of spruce budworm moths caught on sticky boards baited with v i r g i n females, to l a r v a l density was much higher in years of low than in years of high l a r v a l densities; they concluded that trapping e f f i c i e n c y was affected by population density. Evidence of competition between v i r g i n females and pheromone traps has also been found in the codling moth (Howell 1974), the gypsy moth (Elkinton and Carde 1984) and Argyrotaenia citrana (Fernald) (Croft et a_l. 1986). Baker et a l . (1980), however, found no evidence for such competition when trapping Oriental f r u i t moths. I had o r i g i n a l l y planned on testing t h i s hypothesis by comparing recapture rates of released male moths in very low and very high populations, but due to the methods used, the recapture rates were so low that the results were inconclusive (Appendix V). 141 Plot-to-plot v a r i a t i o n makes i t d i f f i c u l t to develop a common pred i c t i v e r e l a t i o n s h i p between catch and l a r v a l density in d i f f e r e n t locations. This problem may be circumvented by averaging several plots to indicate trends on a larger scale and then following up with egg and l a r v a l sampling in s p e c i f i c p l o t s . For example, the mean t o t a l 1984 season's catch in maintained Uni-traps, baited with 0.05% ALD, was s i g n i f i c a n t l y higher in Barnes Lake (631 moths/trap/plot) than in Oregon Jack Creek (326 moths/trap/plot)(t-test; P = 0.02). This corresponds with a s i g n i f i c a n t l y higher 1985 mean l a r v a l density in Barnes Lake (11.1 larvae/three branches/plot) than in Oregon Jack Creek (3.6 larvae/three branches/plot). Another way to reduce the problem of plot-to-plot variation is to monitor populations in the same locations year after year, and to follow the trends over time. This i s beyond the scope and time frame of thi s thesis but some things can be interpreted from these data in combination with those from the Forest Insect and Disease Records (FIDS). Mean catch in non-maintained Uni-traps, baited with 0.05 ALD, increased about f i v e - f o l d from 1984 (251 moths/trap/plot) to 1985 (1224 moths/trap/plot) (paired t-test; P ^  0.01). The FIDS records show that the number of egg masses/10 m2 foliage in an Oregon Jack Creek sample plot also increased, about four-fold from 1984 (68) to 1985 (262) (Erickson and F e r r i s 1986; Erickson and Loranger 1987). These suggest that trap catch of male moths in 1984 and 1985 reflected the numbers of egg laying females in the same years. The l a r v a l density was therefore expected to increase in 1986, but the 142 percentage of infested buds in Oregon Jack Creek only increased from 13% in 1985 to 15% in 1986 (Erickson and F e r r i s 1986; Erickson and Loranger 1987). There appears to have been heavy mortality from the egg to early l a r v a l stage in 1985/86. This demonstrates that an increasing trend in trap catch or egg mass density may not predict the following year's l a r v a l density because of d i f f e r e n t egg and l a r v a l survival rates in d i f f e r e n t years. However, an increasing trend in trap catch could at least warn of a possible increase in population, which could be subsequently v e r i f i e d with more intensive l a r v a l sampling. CONCLUSIONS 1) The percentage of male moths f l y i n g upwind and landing at an ALD lure peaked at 0.05%, thus supporting R o e l o f s threshold hypothesis. 2) The blend of ALD, AC and OH that was similar to that emitted by a v i r g i n female e l i c i t e d s i g n i f i c a n t l y greater percentage upwind f l i g h t , landing at the lure, and copulatory attempts than did the ALD alone. This supports the hypothesis that the entire pheromone blend acts as a unit to stimulate both long range and close range behaviors, as suggested for the cabbage looper by Linn e_t a l . ( 1986). 3) An inverse trend between net upwind ground speed and ALD concentration was found for only the laboratory males at 2-1 m from the lure; the trend was less apparent in wild males and was absent in the lab-wild males. 143 4) The net upwind speed of f l i g h t of a male moth decreased as i t neared the pheromone lure . 5) The net upwind ground speed of f l i g h t of lab-wild moths in response to 0.05% ALD was s i g n i f i c a n t l y lower than that in response to the v i r g i n females but was s i g n i f i c a n t l y increased by the addition.of 0.05% AC or 0.05% AC + 0.05% OH. 6) The e f f e c t s of the minor components on the male's behavior varied between laboratory and wild populations, and between individuals within those populations. This demonstrates that caution must be used when extrapolating results from studies with laboratory insects to wild populations. 7) As hypothesized, the mean catch/trap was s i g n i f i c a n t l y greater in traps hung in the upper canopy compared with those hung 2 m above the ground. However, the c o e f f i c i e n t of variation was the same at both heights. 8) The mean catch/trap was also s i g n i f i c a n t l y greater in traps hung from host trees than in traps hung from tripods that were greater than 5 m away from host trees but contrary to one of my hypothesis, the c o e f f i c i e n t of v a r i a t i o n of trap catch was much lower for traps hung from trees than for traps hung from tripods. 9) Hanging pheromone traps 2 m above the ground in host trees i s recommended for population monitoring work. 144 10) The Uni-trap caught a mean of about 50% of the moths that approached within 1 m of the trap; placing the dichlorvos near the lure instead of in the c o l l e c t i n g bucket did not a f f e c t trap eff i c iency. 11) E f f i c i e n c y dropped with cumulative catch in both the sticky trap and the Uni-trap but the decrease was far more pronounced in the sticky trap. 12) Correlations between trap catch and l a r v a l density in the same year were i n s i g n i f i c a n t in both 1984 and 1985. However, when a lower valley plot with very low l a r v a l density was treated as an o u t l i e r (plot 12) the mean catch/plot in non-maintained Uni-traps was s i g n i f i c a n t l y correlated with l a r v a l densities (r = 0.94-0.97)(P^0.05). 13) Correlations between trap catch in 1984 and l a r v a l density in 1985 were s i g n i f i c a n t (P^0.10) for sticky traps and Uni-traps so long as they were baited with 0.05% ALD and moths were counted and removed from the traps every two days. The correlations were improved (P^0.05) when plot 12 was excluded, but only with the Uni-traps. 14) The c o e f f i c i e n t s of determination for the regressions between l a r v a l density and the preceding year's trap catch were s i g n i f i c a n t l y improved by including estimates of either basal area/ha or foliage biomass/ha as independent variables, but only when plot 12 was excluded from analysis. 145 FUTURE RESEARCH The hypothesis that the pheromone blend acts as a unit to stimulate both long range and close range behavior in the male western spruce budworm moth should be tested further with the sort of f i e l d bioassays described by Linn et al.(l987) for testing the long range responses of the male cabbage looper moths to pheromone blends. By using bubbles to track an adjacent pheromone plume, an observer could walk caged moths upwind towards a pheromone lure and record the distance from the lure at which the moths begin to wing fan or take off upwind. The influences of v i s u a l or t a c t i l e stimuli on close range behavior and the possible interactions with olfactory stimuli should also be investigated in l i g h t of Grant's (1987) findings that copulatory behavior of the spruce budworm male moth appears to be primed by pheromones but released by appropriate chemo-t a c t i l e s t i m u l i . Predicting the population trend of the western spruce budworm with pheromone trap catches i s d i f f i c u l t because the rel a t i o n s h i p between catch and l a r v a l density varies between locations, and is influenced by a number of factors which are not well understood. I doubt that catches in pheromone traps w i l l ever substitute for l a r v a l sampling immediately prior to making a control decision, but the Uni-trap, baited with 0.05% ALD, shows promise of at least indicating where and when more precise sampling methods are required. Further refinements to the trapping system, such as improving i t s e f f i c i e n c y at high 1 46 cumulative catches, might improve c o r r e l a t i o n s . Correlations may also be improved by using the zero-group method to sample plots with very low l a r v a l densities more accurately (Lysyk and Sanders 1987). Variation due to trap-plot location could be reduced by establishing permanent sampling plots and monitoring catch and l a r v a l densities over a number of years. Several years of sampling in such plots would be needed to v e r i f y l o c a l correlations and to see whether the trends in year-to-year trap catch r e f l e c t population trends. 147 REFERENCES Albert, P.J. and Seabrook. 1973. Morphology and histology of the antenna of the male eastern spruce budworm, Choristoneura fumiferana (Clem) (Lepidoptera:Tortricidae). Can. J. Zool. 4: 443-448. Alfaro, R.I. 1986. Mortality and t o p - k i l l in Douglas-fir following d e f o l i a t i o n by the western spruce budworm in B r i t i s h Columbia. J. Entomol. Soc. B.C. 83:19-30. Alfaro, R.I., G.A. Van Sickle, A.J. Thomson and E. Wegwitz. 1982. Tree mortality and r a d i a l growth losses caused by the western spruce budworm in a Douglas-fir stand in B r i t i s h Columbia. Can. J . For. Res. 12:780-787. Alfaro, R.I., A,J, Thomson and G.A. Van Sickle. 1985. Quantification of Douglas-fir growth losses caused by western spruce budworm d e f o l i a t i o n using stem analysis. Can. J. For. Res. 15:5-9. Alford, A.R., P.J. S i l k , M. McLure, C. Gibson and J. F i t z p a t r i c k . 1983. Behavioral e f f e c t s of secondary components of the sex pheromone of the eastern spruce budworm, Choristoneura fumiferana (Lepidoptera:Tortricidae). Can. Ent. 115:1053-1058. Alfo r d , A.R. and P.J. S i l k . 1984. Behavioral e f f e c t s of secondary components of sex pheromone of western spruce budworm, Choristoneura occidentalis Free. J . Chem. Ecol. 10:265-270. AliNiazee, M.T. 1983. Monitoring the filbertworm, Melissopus  latiferreanus (Lepidoptera:01ethreutidae), with sex attractant traps: effect of trap design and placement on moth catches. Environ. Entomol. 12:141-146. AliNiazee, M.T. and E.M. Stafford. 1972. Sex pheromone studies with the omnivorous l e a f r o l l e r : e ffect of various environmental factors on a t t r a c t i o n of males to the traps baited with v i r g i n females. Ann. Entomol. Soc. Am. 65:958-961. All e n , D.C, L.P. Abrahamson, D.A. Eggen, G.N. Lanier, S.R. Swier, R.S. Kelley, and M. Auger. 1986. Monitoring spruce budworm (Lepidoptera:Tortricidae) populations with pheromone-baited traps. Environ. Entomol. 15:152-165. A n g e r i l l i , N., and J.A. McLean. 1984. Windtunnel and f i e l d observations of western spruce budworm responses to pheromone baited traps. J. Entomol. Soc. B.C. 79: 10-16. 148 Baker, T.C. 1986. Pheromone-modulated movements of f l y i n g moths, vn Payne, T.L., M.C. Birch, and C.E.J. Kennedy (eds). Mechanisms in Insect O l f a c t i o n . Clarendon Press, Oxford, pp. 39-48. Baker, T.C. and R.T. Carde. 1979. Analysis of pheromone-mediated behaviors in male Grapholitha molesta, the Oriental f r u i t moth (Lepidoptera:Tortricidae). Environ. Entomol. 8:956-968. Baker, T.C. and W.L. Roelofs. 1981. I n i t i a t i o n of Oriental f r u i t moth male response to pheromone concentrations in the f i e l d . Environ. Entomol. 10:211-218. Baker, T.C, R.T. Carde' and W.L. Roelofs. 1976. Behavioral responses of male Argyrotaenia velutinana (Lepidoptera:Tortricidae) to components of i t s sex pheromone. J. Chem. Ecol. 2:333-352. Baker, T.C, R.T. Carde' and B.A. Croft. 1980. Relationship between pheromone trap capture and emergence of adult Oriental f r u i t moths, Grapholitha molesta (Lepidoptera:Tortricidae). Can. Ent. 112:11-15. Barrer, P.M. M.J. Lucey and A. Shani. 1987. Variation in re l a t i v e quantities of airborne sex pheromone components from individual female Ephestia c a u t e l l a (Lepidoptera:Pyralidae). J. Chem. Ecol. 13:639-653. Beroza, M.C.R., CR. Gentry, J.L. Blythe and G.M. Mushik. 1973. Isomer content and other factors influencing capture of or i e n t a l f r u i t moth by synthetic pheromone traps. J. Econ. Entomol. 66: 1307-1311. Birch, M.C, ed. 1974. Pheromones. American Else v i e r Publishing Co. Inc. N.Y. 495 pp. Bl a i s , J.R. 1957. Some relationships of the spruce budworm, Choristoneura fumiferana (Clem.) to black spruce, Picea mariana (Moench) Voss. For. Chron. 33:364-372. Bode, W.M., D. Asquith and J.P. Tette. 1973. Sex attractants and traps for tufted apple budmoth and redbanded l e a f r o l l e r males. J . Econ. Entomol. 66:1129-1130. Boiler, E. 1972. Behavioral aspects of mass-rearing of insects. Entomophaga. 17: 9-25. Borden, J.H. and J.A. McLean. 1981. Pheromone-based suppression of ambrosia beetles in i n d u s t r i a l timber processing areas, pp. 1 33-154. ijo M i t c h e l l , E.R. (ed.), Management of Insect Pests with Semiochemicals: Concepts and Practice. Plenum Press. N.Y. 514 pp. 149 Box, G.E.P. 1949. A general d i s t r i b u t i o n theory for a class of l i k e l i h o o d c r i t e r i a . Biometrika. 36:317-346. Bradshaw, J.W.A., R. Baker and J.C. Lisk. 1983. Separate orientation and releaser components in a sex pheromone. Nature. 304:265-267. Brubaker, L.B. and S.K. Greene. 1979. D i f f e r e n t i a l e f f e cts of Douglas-fir tussock moth and western spruce budworm de f o l i a t i o n on r a d i a l growth of grand f i r and Douglas-fir. Can. J . For. Res. 9:95-105. Butenandt, A., R. Beckmann, D. Stamm and E. Hecker. 1959. Uber den Sexuallockstoff des Seidenspinners Bombyx mori. Reindarstellung und Konstitutionsermittlung. Z. Naturforsch. 14b:283-284. Butt, B.A., T.P. McGovern, M.Beroza and D.O. Hathaway. 1974. Codling moth: Cage and f i e l d evaluation of traps baited with a synthetic sex attractant. J . Econ. Entomol. 67:37-40. Campbell, R.W. and T.R. Torgersen. 1982. Some eff e c t s of predaceous ants on western spruce budworm pupae in North Central Washington. Environ. Entomol. 11:111-114. Campbell, R.W., T.R. Torgersen and N. Srivastava. 1983a. A suggested role for predaceous birds and ants in the population dynamics of the western spruce budworm. Forest S c i . 29:779-790. Campbell, R.W., R.C. Beckwith and T.R. Torgersen. 1983b. Numerical behavior of some western spruce budworm (Lepidoptera:Tortricidae) populations in Washington and Idaho. Environ. Entomol. 12:1360-1366. Campbell, R.W. N. Srivastava, T.R. Torgersen, and R.C. Beckwith. 1984. Patterns of occurrence of the western spruce budworm (Lepidoptera:Tortricidae): Larvae, pupae and pupal exuviae, and egg masses. Environ. Entomol. 13:522-530. Carde", R.T. 1 979. Behavioral responses of moths to female-produced pheromones and the u t i l i z a t i o n of attractant-baited traps for population monitoring, pp 286-315. ir\ Rabb, R.L. and G.G. Kennedy (eds.), Movement of Highly Mobile Insects: Concepts and Methodology in Research. North Carolina State University, Raleigh. 456 pp. Carde", R.T. and T.E. Hagaman. 1979. Behavioral responses of the gypsy moth in a wind tunnel to air-borne enantiomers of disparlure. Environ. Entomol. 8:475-484. 150 Carde', R.T. and T.E. Hagaman. 1984. Mate location strategies of gypsy moths in dense populations. J. Chem. Ecol. 10:25-31. Carde', R.T., T. Baker and W. Roelofs. 1975. Ethological function of components of a sex attractant system for Oriental f r u i t moth males, Grapholitha molesta. J . Chem. Ecol. 1:475-491. Carolin, V.M. and W.K. Coulter. 1972. Sampling populations of the western spruce budworm and predicting d e f o l i a t i o n on Douglas-fir in eastern Oregon. U.S. Dep. Agric. For. Serv. Res. Pap. PNW-149. Pac. Northwest For. Range Exp. Stn. Portland, Oreg. 38 pp. Carolin, V.M. and W.K. Coulter. 1975. Comparison of western spruce budworm populations and damage on grand f i r and Douglas-fir trees. U.S. Dep. Agric. For. Serv. Res. Pap. PNW-195. Pac. Northwest For. Range Exp. Stn. Portland, Oreg. 16 pp. Carpenter, J.E. and A.N. Sparks. 1981. The s p e c i f i c i t y of Hel i o t h i s zea pheromone components in e l i c i t i n g pre-copulatory responses from H. zea male moths. J. Georgia . Entomol. Soc. 17:87-93. Chapman, R.F. 1982. Chemoreception: the significance of receptor numbers. Adv. in Insect Phys. 16: 247-356. C o l l i s , D.E. and G.A. Van S i c k l e . 1978. Damage appraisal issues in spruce budworm defoliated stands of Douglas-fir in 1977. Can. For. Serv. Pac. For. Res. Cent. BC-P-19- 1978. 8 pp. Cory, H.T., G.E. Daterman, G.D. Daves, J r . , L.L. Sower, R.F. Shepherd, and C.F. Sanders. 1982. Chemistry and f i e l d evaluation of the sex pheromone of western spruce budworm, Choristoneura occidentalis, Freeman. J. Chem. Ecol. 8: 339-350. Coudriet, D.L. and T.J. Henneberry. 1976. Captures of male cabbage loopers and pink bollworm: Effect of trap design and pheromone. J. Econ. Entomol. 69:603-605. Croft, B.A., A.L. Knight, J.L. Flexner and R.W. M i l l e r . 1986. Competition between caged v i r g i n female Argyrotaenia  citrana (Lepidoptera:Tortricidae) and pheromone traps for capture of released males in a semi-enclosed courtyard. Environ. Entomol. 15:232-239. Culver, D.J. and M.M. Barnes. 1977. Contributions to the use of the synthetic pheromone in monitoring codling moth populations. J. Econ. Entomol. 70:489-492. 151 Daterman, G.E. 1974. Synthetic sex pheromone for detection survey of European pine shoot moth. U.S. Dep. Agric. For. Serv. Res. Pap. PNW-180. 12pp. Daterman, G.E. 1979. Role of pheromones in forest insect survey and control, pp. 385-404. i_n Rudinsky, J.A., (ed) Forest Insect Survey and Control. Oregon State University. C o r v a l l i s . 472 pp. Daterman, G.E. 1982. Monitoring insects with pheromones: Trapping objectives and bait formulations, pp 195-212. iri A.F. Kydonieus and M.B. Beroza (eds)., Insect Suppression with Controlled Release Pheromone Systems, Vol. I. CRC Press, Inc. Boca Raton, F l o r i d a . 274 pp. Daterman, G.E. and D. McComb. 1970. Female sex attractant for survey trapping European pine shoot moth. J. Econ. Entomol. 63:1406-1409. Daterman, G.E., L.J. Peterson, R.G. Robbins, L.L. Sower, G. Doyle Daves, J r . and R.G. Smith. 1976. Laboratory and f i e l d bioassay of the Douglas-fir tussock moth pheromone, (£)-6-Heneicosen-11-one. Environ. Entomol. 5:1187-1190. Daterman, G.E., R.L. Livingston, J.M. Wenz, and L.L. Sower. 1979a. How to use pheromone traps to determine outbreak po t e n t i a l . U.S. Dep. Agric. Combined Forest Pest Research  and Development Program Agriculture Handbook No. 546. 11 pp. Daterman, G.E., L.L. Sower and C. Sartwell. 1979b. Challenges in the use of pheromone for managing western forest Lepidoptera. pp. 243-254. _in Leonhardt, B.A. and M. Beroza (eds)., Insect Pheromone Technology: Chemistry and Applications. Symposium Series 190. American Chemical Society. Washington, DC. 260 pp. Daterman, G.E., H.T. Cory, L.L. Sower, and G.D. Daves, J r . 1984. Sex pheromone of a conifer-feeding budworm, Choristoneura retiniana, Walsingham. J. Chem. Ecol. 10:153-160. Elkinton, J.S. and R.T. Carde'. 1983. Appetitive f l i g h t behavior of male gypsy moths (Lepidoptera:Lymantriidae). Environ. Entomol. 12:1702-1707. Elkinton, J.S. and R.D. Childs. 1983. E f f i c i e n c y of two gypsy moth (Lepidoptera:Lymantriidae) pheromone-baited traps. Environ. Entomol. 12:1519-1525. Elkinton, J.S. and R.T. Carde'. 1984. Effect of wild and laboratory-reared female gypsy moth (Lepidoptera:Lymantriidae) on the capture of males in pheromone-baited traps. Environ. Entomol. 13:1377-1385. 152 Ennis, T.J. and N. Charlebois. 1979. A release-recapture experiment with normal and ir r a d i a t e d spruce budworm males. Dep. Environ., Can. For. Serv., Ottawa, Ont. Bi-mon Res. Notes" 3572): 9-10. Erickson, R.D. and R.L. F e r r i s . 1986. Forest Insect and Disease Conditions, Kamloops Forest Region, 1985. Can. For. Serv. FIDS F i l e Report 86-2. 33 pp. Erickson, R.D. and J. Loranger. 1987. Forest Insect and Disease Conditions, Kamloops Forest Region, 1986. Can. For. Serv. FIDS F i l e Report 87-2. 37 pp. F e l l i n , D.G. and P.W. Hengel. 1983. Deploying pheromone-baited traps for the western spruce budworm and other d e f o l i a t i n g insects. U.S. Dep. Agric. For. Serv. Res. Pap. Note INT- 330. Intermountain For. and Range Exp. Stn., Missoula, Montana. 7 pp. Fletcher, L.W., H.V. Claborn, J.P. Turner and E. Lorez. 1968. Difference in response of two strains of screw-worm f l i e s to male pheromones. J . Econ. Entomol. 61:1386-1388. Furniss, R.L. and V.M. Carolin. 1977. Western forest insects. U.S. Dep. Agric. For. Serv. Misc. Publ. No. 1339. 654 pp. Grant, G.G. 1987. Copulatory behavior of spruce budworm, Choristoneura fumiferana (Lepidoptera:Tortricidae): experimental analysis of the role of the sex pheromone and . associated s t i m u l i . Ann. Entomol. Soc. Am. 80:78-88 Gray, T.G., K.N. Slessor, G.G. Grant, R.F. Shepherd, E.H. Holsten, and A.S. Tracey. 1984a. I d e n t i f i c a t i o n and f i e l d t esting of pheromone components of Choristoneura orae (Lepidoptera:Tortricidae). Can. Ent. 116:51-56. Gray, T.G., K.N. Slessor, R.F. Shepherd, G.G. Grant and J.F. Manville. 1984b. European pine shoot moth, Rhyacionia  buoliana (Lepidoptera:Tortricidae): I d e n t i f i c a t i o n of additional pheromone components resulting in an improved lure. Can. Ent. 116:1525-1532. Greenbank, D.O., G.W. Schaefer, and R.C. Rainey. 1980. Spruce budworm (Lepidoptera:Tortricidae) moth f l i g h t and d i s p e r s a l : New understanding from canopy observations, radar, and a i r c r a f t . Mem. Ent. Soc. Can. 110. 49 pp. Haines, L.C. 1983. Wind tunnel studies on the ef f e c t s of secondary sex pheromone components on the behavior of male Egyptian cotton leafworm moths, Spodoptera l i t t o r a l i s . Physiol. Entomol. 8:29-40. 153 Harris, J.W.E., R.I. Alfaro, A.G. Dawson and R.G. Brown. 1985. The spruce budworm in B r i t i s h Columbia 1909-1983. Can. For. Serv. Pac. For. Res. Cent. Inf. Rep. BC-X-257. Haynes, K.F., L.K. Gaston. M. Mistrot Pope and T.C. Baker. 1984. Potential for evolution of resistance to pheromones: Interindividual and interpopulational v a r i a t i o n in chemical communication system of pink bollworm moth. J. Chem. Ecol. 10:1551-1565. Houseweart, M.W., D.T. Jennings and C.J. Sanders. 1981. Variables associated with pheromone traps for monitoring spruce budworm populations (Lepidoptera:Tortricidae). Can. Ent. 113:527-537. Howell, J.F. 1972. An improved sex attractant trap for codling moths. J. Econ. Entomol. 65:609-611. Howell, J.F. 1974. The competitive e f f e c t of f i e l d populations of codling moth on sex attractant trap e f f i c i e n c y . Environ. Entomol. 3:803-807. Hsiao, T.H. and C. Hsiao. 1973. Benomyl: a novel drug for c o n t r o l l i n g a microsporidian disease of the a l f a l f a weevil. J. Invertebr. Pathol. 22: 303-304. Huettel, M.D. 1976. Monitoring the qual i t y of laboratory-reared insects: a b i o l o g i c a l and behavioral perspective. Environ. Entomol. 5: 807-814. Husch, B., C F . M i l l e r and T.W. Beers. 1972. Forest Mensuration. 2nd. ed. The Ronald Press Co. N.Y. 410 pp. Jobin, L.J. 1985. Development of a large-capacity pheromone trap for monitoring forest insect pest populations, pp. 243-245. in C J . Sanders, R.W. Stark, E.J. Mullins, and J. Murphy Teds) . , Recent Advances in Spruce Budworms Research., Proceedings of the CANUSA Spruce Budworms Research Symposium., Bangor, Maine., September 16-20, 1984. 527 pp. Kaae, R.S. and H.H. Shorey. 1973. Sex pheromones of Lepidoptera. 44. Influence of environmental conditions on the location of pheromone communication and mating in Pectinophora gossypiella. Environ. Entomol. 2:1081-1 084. Kai s s l i n g , K.E. 1971. Insect Olfaction, pp 351-431 in L« M« Beidler, (ed.),. Olfaction, Handbook of Sensory Physiology, Volume IV. Springer-Verlag. B e r l i n . 518 pp. Kendall, D.M., D.T. Jennings and M.W. Houseweart. 1982. A large-capacity pheromone trap for spruce budworm moths (Lepidoptera:Tortricidae). Can. Ent. 114:461-463. 1 54 Kennedy, G.G. 1975. Trap design and other factors influencing capture of male potato tuberworm moths by v i r g i n female baited traps. J . Econ. Entomol. 68:305-308. Kuenen, L.P.S. and T.C. Baker. 1982a. Optomotor regulation of ground v e l o c i t y in moths during f l i g h t to sex pheromone at diff e r e n t heights. Physiol. Entomol. 7:193-202. Kuenen, L.P.S. and T.C. Baker. 1982b. The effects of pheromone concentration on the f l i g h t behavior of the Oriental f r u i t moth, Grapholitha molesta. Physiol. Entomol. 7:423-434. Kydonieus, A.F. and M. Beroza, (eds). 1982. Insect Suppression with Controlled Release Pheromone Systems. Vols. 1 & 2. CRC Press, Inc. Boca Raton, F l o r i d a . 586 pp. Lewis, T. and E.D.M. McCauley. 1976. Design and evaluation of sex-attractant traps for pea moth, Cydia nigricana (Steph.) and the eff e c t of plume shape on catches. Ecol. Entomol. 1s175-187. Liebhold, A.M. and W.J.A. Volney. 1984a. Effect of foliage proximity on a t t r a c t i o n of Choristoneura o c c i d e n t a l i s and C. retiniana (Lepidoptera:Tortricidae) to pheromone sources. J. Chem. Ecol. 10:217-227. Liebhold, A.M. and W.J.A. Volney. 1984b. Effect of temporal factors on reproductive i s o l a t i o n between Choristoneura  occidentalis and C. retiniana (Lepidoptera:Tortricidae). Can. Ent. 116:991-1005. Liebhold, A.M. and J.A. Volney. 1985. Effects of attractant composition and release rate on attr a c t i o n of male Choristoneura retiniana, C. occidentalis, and C. carnana (Lepidoptera:Tortricidae). Can. Ent. 117:447-457. Lindgren, B.S. 1983. A multiple funnel trap for s c o l y t i d beetles (Coleoptera). Can. Ent. 115:299-302. Lindgren, B.S., J.D. Sweeney and J.A. McLean. 1984. Comparative evaluation of traps for monitoring the Douglas-f i r tussock moth (Lepidoptera:Lymantriidae). J . Entomol. Soc. B.C. 81:3-9. Linn, C.E., J r . and L.K. Gaston. 1981a. Behavioral responses of male Trichoplusia ni in a sustained-flight tunnel to the two sex pheromone components. Environ. Entomol. 10:379-385. Linn, C.E., J r . and L.K. Gaston. 1981b. Behavioral function of the components and the blend of the sex pheromone of the cabbage looper, Tr ichoplusia n i . Environ. Entomol. 10:751-755. 155 Linn, C.E., J r . , M.G. Campbell and W.L. Roelofs. 1986. Male moth s e n s i t i v i t y to multicomponent pheromones: C r i t i c a l role of female-released blend in determining the functional role of components and active space of the pheromone. J . Chem. Ecol. 12:659-668. Linn, C.E., J r . , M.G. Campbell and W.L. Roelofs. 1987. Pheromone components and active spaces: what do moths smell and where do they smell i t ? Science 237:650-652 Livingston, R.L. and G.E. Daterman. 1977. Surveying for Douglas-fir tussock moth with pheromone. B u l l . Entomol. Soc. Am. 23:172-174. Lysyk, T.J. and C.J. Sanders. 1987. A method for sampling endemic populations of the spruce budworm (Lepidoptera:Tortricidae) based on proportion of empty sample units. Can. For. Serv. Great Lakes For. Cent. Inf. Rep. O-X-382. 17 pp. Madsen, H.F. and J.M. Vakenti.. 1973. Codling moth: Use of codlemone R -baited traps and visu a l detection of entries to determine need of sprays. Environ. Entomol. 2:677-679. Mankin, R.W., K.W. Vick, J.A. C o f f e l t , and B.A. Weaver. 1983. Pheromone-mediated f l i g h t by male Plodia interpunctella (HUbner) (Lepidoptera:Pyralidae). Environ. Entomol. 12:1218-1222. Marsh, D., J.S. Kennedy and A.R. Ludlow. 1978. An analysis of anemotactic zigzagging f l i g h t in male moths stimulated by pheromone. Physiol. Entomol. 3:221-240. Masson, C. 1984. Neural basis of o l f a c t i o n in insects, pp 245-255. in Bolis, L., R.D. Keynes and S.H.P. Maddrell (eds), Comparative Physiology of Sensory Systems. Cambridge Univ. Press. Cambridge. 660 pp. McLean, J.A. and J.H. Borden. 1979. An operational pheromone-based suppression program for an ambrosia beetle, Gnathotrichus sulcatus, in a commercial sawmill. J. Econ. Entomol. 72:165-172. M i l l e r , C.A. and G.A. McDougall. 1973. Spruce budworm moth trapping using v i r g i n females. Can. J . Zool. 51:853-858. Minks, A.K. 1971. Decreased sex pheromone production in an i n -bred stock of the summerfruit t o r t r i x moth, Adoxophyes  orana. Entomol. Exp. Appl. 14: 361-364. Minks, A.K. 1977. Manipulation of insect pests of a g r i c u l t u r a l crops. pp. 353-367. in Shorey, H.H. and J.J. McKelvey, J r . , (eds)., Chemical Control of Insect Behavior: Theory and Application. Wiley-Interscience. N.Y. 414 pp. 156 M i t c h e l l , E.R., ed. 1981. Management of Insect Pests with Semiochemicals: Concepts and Practice. Plenum Press. N.Y. 514 pp. Morse, D., R. Szit t n e r , G.G. Grant and E.A. Meighen. 1982. Rate of pheromone release by ind i v i d u a l spruce budworm moths. J . Insect Physiol. 28:863-866. Murlis, J., B.W. Bettany, J. Kelley and L. Martin. 1982. The analysis of f l i g h t paths of male Egyptian cotton leafworm moths, Spodoptera l i t t o r a l i s , to a sex pheromone source in the f i e l d . Physiol. Entomol. 7:435-441. Mustaparta, H. 1984. Olfaction. in B e l l , W.J. and R.T. Carde' (eds)., Chemical Ecology of Insects. Sinauer Associates, Inc. Sunderland, Massachusetts. 524 pp. O'Connell, R.J. 1986. Chemical communication in invertebrates. Experentia 42:232-241. Outram, I. 1971. Aspects of mating in the spruce budworm Choristoneura fumiferana (Lepidoptera:Tortricidae). Can. Ent. 103:1121-1128. Palaniswamy, P., E.W. Underhill, W.F. Steck and M.D. Chisholm. 1983. Responses of male redbacked cutworm, Euxoa  ochrogaster (Lepidoptera:Noctuidae), to sex pheromone components in a f l i g h t tunnel. Environ. Entomol. 12:748- ' 752. Payne, T. 1974. Pheromone perception, pp. 35-61. in Birch, M.C. (ed),. Pheromones. American Elsevier Publishing Co., Inc. N.Y. 495 pp. Pendrel, B.A. 1985a. Population d i s t r i b u t i o n of forest tent caterpillar-1984 described through pheromone trapping. Can. For. Serv. Maritimes For. Res. Cent. Technical Note, No. 137. 4 pp. Pendrel, B.A. 1985b. Population d i s t r i b u t i o n of Jack pine budworm-1984 described through pheromone trapping. Can. For . Serv. Maritimes For. Res. Cent. Technical Note, No. 133. 4 pp. Perez, D. and R. Rozas. 1984. An inexpensive and r e l i a b l e electroantennometer with automatic base l i n e offset and d r i f t c anceller. Physiol. Entomol. 9: 433-436. Pope, M.M., L.K. Gaston and T.C. Baker. 1982. Composition, qu a n t i f i c a t i o n , and p e r i o d i c i t y of sex pheromone gland v o l a t i l e s from individual H e l i o t h i s virescens females. J. Chem. Ecol. 8:1043-1055. 157 Powell, J.A. 1980. Nomenclature of nearctic conifer-feeding Choristoneura (Lepidoptera:Tortricidae): h i s t o r i c a l review and present status. U.S. Dep. Agric. For. Serv. Gen. Tech. Rep. PNW-100. Pac. Northwest For. Range Exp. Stn. 18 pp. Preisner, E. 1986. Correlating sensory and behavioral responses in multichemical pheromone systems of Lepidoptera. pp. 225-233. i_n Payne, T.L., M.C. Birch, and C.E.J. Kennedy, (eds),. Mechanisms in Insect O l f a c t i o n . Clarendon Press. Oxford. 364 pp. Ramaswamy, S.B. and R.T. Carde'. 1982. Nonsaturating traps and l o n g - l i f e attractant lures for monitoring spruce budworm males. J . Econ. Entomol. 75:126-129. Ramaswamy, S.B. and R.T. Carde'. 1984. Rate of release of spruce budworm pheromone from v i r g i n females and synthetic lures. J . Chem. Ecol. 10:1-7. Ramaswamy, S.B., R.T. Carde'and J.A. Witter. 1983. Relationships between catch in pheromone-baited traps and l a r v a l density of the spruce budworm, Choristoneura  fumiferana (Lepidoptera:Tortricidae). Can. Ent. 115:1437-1 443. Richerson, J.V. 1977. Pheromone-mediated behavior of the gypsy moth. J . Chem. Ecol. 3:291-308. Richerson, J.V., E.A. Brown and E.A. Cameron. 1976. Pre-mating sexual a c t i v i t y of gypsy moth males in small plot f i e l d tests (Lymantria (= Porthetria) dispar (L.): Lymantriidae). Can. Ent. 109:439-448. Riedl, H. and B.A. Croft. 1974. A study of pheromone trap catches in rel a t i o n to codling moth (Lepidoptera:Olethreutidae) damage. Can. Ent. 106:525-537. Robertson, J.L. 1979. Rearing the western spruce budworm. U.S. Dep. Agric. For. Serv. 17 pp. Robertson, J.L. 1985. Choristoneura occidentalis and Choristoneura fumi ferana. pp. 227-236 in Singh, P. and R.F. Moore (Eds), Handbook of Insect Rearing, Volume 2. Els e v i e r , Amsterdam. Roelofs, W.L. 1977. The scope and li m i t a t i o n s of the electroantennogram technique in i d e n t i f y i n g pheromone components, pp. 147-165 in McFarlane, N.R. (Ed), Crop Protection Agents-Their B i o l o g i c a l Evaluation. Academic Press, London. 638pp Roelofs, W.L. 1978. Threshold hypothesis for pheromone perception. J . Chem. Ecol. 4:685-699. 158 Roelofs, W.L. and R.L. Brown. 1982. Pheromones and evolutionary relationships of T o r t r i c i d a e . Annu. Rev. Ecol. Syst. 13:395-422. Roelofs, W.L. and R.T. Carde". 1977. Responses of Lepidoptera to synthetic sex pheromone chemicals and their analogues. Ann. Rev. Entomol. 22:377-405. Sanders, C.J. 1978. Evaluation of sex attractant traps for monitoring spruce budworm populations (Lepidoptera:Tortricidae). Can. Ent. 110:43-50. Sanders, C.J. 1981a. Sex attractant traps: Their role in the management of spruce budworm. pp. 75-91. in E.R. Mitc h e l l ed., Management of Insect Pests with Semiochemicals: Concepts and Practice. Plenum Press. New York. 514 pp. Sanders, C.J. 1981b. Release rates and at t r a c t i o n of pvc lures containing synthetic sex attractant of the spruce budworm, Choristoneura fumiferana (Lepidoptera:Tortricidae). Can. Ent. 113:103-112. Sanders, C.J. 1983. Local dispersal of male spruce budworm (Lepidoptera:Tortricidae) moths determined by mark, release, and recapture. Can. Ent. 115:1065-1070. Sanders, C.J. 1984a. Sex pheromone of the spruce budworm (Lepidoptera:Tortricidae): evidence for a missing component. Can. Ent. 116:93-100. Sanders, C.J. 1984b. Sex pheromone traps and lures for monitoring spruce budworm populations - the Ontario experience. pp. 17-22. in Proceedings: new and improved techniques for monitoring and evaluating spruce budworm populations. U.S. Dep. Agric. For. Serv. Gen. Tech. Rep. NE-88. 71 pp. Sanders, C.J. 1985. Sex pheromone as a trigger of female moth dis p e r s a l . pp. 113-114. ijn C.J. Sanders, R.W. Stark, E.J. Mullins, and J. Murphy (eds)., Recent Advances in Spruce Budworms Research., Proceedings of the CANUSA Spruce Budworms Research Symposium., Bangor, Maine., September 16-20, 1984. 527 pp. Sanders, C.J. 1986a. Evaluation of high-capacity, nonsaturating sex pheromone traps for monitoring population densities of spruce budworm (Lepidoptera:Tortricidae). Can. Ent. 118:611-619. Sanders, C.J. 1986b. The role of pheromone concentration in male moth f l i g h t behavior, pp. 117-122. in Payne, T.L., M.C. Birch, and C.E.J. Kennedy (eds),. Mechanisms in Insect O l f a c t i o n . Clarendon Press. Oxford. 364 pp. 159 Sanders, C.J. 1986c. Accumulated dead insects and k i l l i n g agents reduce catches of spruce budworm (Lepidoptera:Tortricidae) male moths in sex pheromone traps. J . Econ. Entomol. 79:1351-1353. Sanders, C.J., G.S. Lucuik and R.M. Fletcher. 1981. Responses of male spruce budworm (Lepidoptera:Tortricidae) to d i f f e r e n t concentrations of sex pheromone as measured in a sustained-flight wind tunnel. Can. Ent. 113:943-948. Sanders, C.J. and G.S. Lucuik. 1972. Factors a f f e c t i n g c a l l i n g by female eastern spruce budworm, Choristoneura fumiferana (Lepidoptera:Tortricidae). Can. Ent. 104:1751-1762. Sanders, C.J. and G.S. Lucuik. 1975. E f f e c t s of photoperiod and size on f l i g h t a c t i v i t y and oviposition in the eastern spruce budworm (Lepidoptera:Tortricidae). Can. Ent. 107:1289-1299. Sanders, C.J. and E.A. Meighen. 1987. Controlled-release sex pheromone lures for monitoring spruce budworm populations. Can. Ent. 119:305-313. Sartwell, C , G. Daterman and D.B. Twardus. 1985. Moth captures in pheromone-baited traps r e l a t i v e to subsequent d e f o l i a t i o n of Douglas-fir by western spruce budworm. p 240 i_n C.J. Sanders, R.W. Stark, E.J. Mullins, and J. Murphy (eds)., Recent Advances in Spruce Budworms Research., Proceedings of the CANUSA Spruce Budworms Research Symposium., Bangor, Maine., September 16-20, 1984. 527 pp. Seabrook, W.D. 1977. Insect chemosensory responses to other insects. pp 15-43. in Shorey, H.H. and J.J. McKelvey, J r . , (eds),. Chemical Control of Insect Behavior: Theory and Application. Wiley-Interscience. N.Y. 414 pp. Seabrook, W.D. 1978. Neurobiological contributions to understanding insect pheromone systems. Ann. Rev. Entomol. 23: 471-485. Shepherd, R.F. 1979. Comparison of the d a i l y cycle of adult behavior of fiv e forest lepidoptera from Western Canada, and t h e i r response to pheromone traps. B u l l . Soc. Entomol. Suisse. 52:157-168. Shepherd, R.F. 1985a. Spruce budworm traps: an evaluation of four designs, pp. 221-226. in Safranyik, L. (ed),. The Role of the Host in the Population Dynamics of Forest Insects., Proceedings of the IUFRO Conference., Banff, Alberta., September 4-7, 1983. 160 Shepherd, R.F. 1985b. A theory on the effects of diverse host-climate environments in B r i t i s h Columbia on the dynamics of western spruce budworm. pp. 60-70. in C.J. Sanders, R.W. Stark, E.J. Mullins, and J. Murphy (eds)., Recent Advances in Spruce Budworms Research., Proceedings of the CANUSA Spruce Budworms Research Symposium., Bangor, Maine., September 16-20, 1984. 527 pp. Shepherd, R., J.W.E. Harris, G.A. Van Sickle, L. Fiddick and L. McMullen. 1977. Status of western spruce budworm on Douglas-fir in B r i t i s h Columbia. Can. For. Serv. Pac. For. Res. Cent., Pest Report. 14 pp. Shepherd, R.F., T.G. Gray, R.J. Chorney and G.E. Daterman. 1985. Pest management of Douglas-fir tussock moth, Orgyia  pseudotsugata (Lepidoptera:Lymantriidae): Monitoring endemic populations with pheromone traps to detect incipient outbreaks. Can. Ent. 117:839-848. Shorey, H.H. and J . J . McKelvey, J r . , (eds). 1977. Chemical Control of Insect Behavior: Theory and Application. Wiley-Interscience. N.Y. 414 pp. S i l k , P.J. and L.P.S. Kuenen. 1986. Spruce budworm (Choristoneura fumiferana) pheromone chemistry and behavioral responses to pheromone components and analogs. J. Chem. Ecol. 12:367-383. S i l k , P.J., C.J. Weisner, S.H. Tan, R.J. Ross, and G.G. Grant. 1982. Sex pheromone chemistry of the western spruce budworm, Choristoneura occidentalis Free. J . Chem. Ecol. 8: 351-362. S i l v e r s t e i n , R.M. 1981. Pheromones: background and potential for use in insect pest c o n t r o l . Science 213: 1326-1332. Sower, L.L., D.W. Hagstrom, and J.S. Long. 1973. Comparison of the female pheromones of a wild and a laboratory s t r a i n of Cadra c a u t e l l a , and a male responsiveness to the pheromone extracts. Ann. Entomol. Soc. Am. 66: 484-485. Sower, L.L. and G.E. Daterman. 1985. Premating searching a c t i v i t y of male western spruce budworm moths Choristoneura  occidentalis (Lepidoptera:Tortricidae). Can. Ent. 1 1 7: 1273-1 274. Standish, J.T., G.H. Manning and J.P. Demaerschalk. 1985. Development of biomass equations for B r i t i s h Columbia tree species. Can. For. Serv. Pac. For. Res. Cent., Information  Rep. BC-X-264. 47 pp. 161 Stock, M.W. and P.J. C a s t r o v i l l o . 1981. Genetic relationships among representative populations of five Choristoneura species: C. occidentalis, C. retiniana, C. biennis, C. lambertiana, and C. fumiferana (Lepidoptera:Tortricidae). Can. Ent. 113:857-865. Stock, M.W. and J.L. Robertson. 1982. Quality assessment and control in a western spruce budworm laboratory colony. Entomol. Exp. Appl. 32: 28-32. Struble, D.L. 1983. Pheromone traps for monitoring moth (Lepidoptera) abundances: evaluation of cone-orifice and omni-directional designs. Can. Ent. 115:59-65. Sweeney, J.D. and J.A. McLean. 1987. Effect of sublethal infect i o n levels of Nosema sp. on the pheromone-mediated behavior of the western spruce budworm, Choristoneura  occidentalis Freeman (Lepidoptera:Tortricidae). Can. Ent. 119:587-594. Tingle, F.C. and E.R. M i t c h e l l . 1975. Capture of Spodoptera  frugiperda and S. exigua in pheromone traps. J . Econ. Entomol. 68:613-615. Toscano, N.C., A.J. Mueller, V. Sevacherian, R.K. Sharma, T. N i i l u s and H.T. Reynolds. 1974. Insecticide applications based on hexalure R trap catches versus automatic schedule treatments for pink bollworm co n t r o l . J. Econ. Entomol. 67:522-524. T r o t t i e r , R.I., I. Rivard and W.T.A. Nelson. 1975. Bait traps for monitoring apple maggot a c t i v i t y and t h e i r use for timing control sprays. J. Econ. Entomol. 68:211-213. Turnock, W.J. 1987. Predicting l a r v a l abundance of the bertha armyworm, Mamestra configurata Wlk., in Manitoba from catches of male moths in sex attractant traps. Can. Ent. 119:167-178. Unger, L.S. 1983. Spruce budworms in B.C. Can. For. Serv. Pac. For. Res. Cent. Pest Leaflet No. 3K 4 pp. Vakenti, J.M. and H.F. Madsen. 1976. Codling moth (Lepidoptera:01ethreutidae): monitoring populations in apple orchards with sex pheromone traps. Can. Ent. 108:433-438. Van Sickle, G.A. 1987. Host responses, pp 57-70. in M.H. Brookes, R.W. Campbell, J.J. Colbert, R.G. M i t c h e l l , and R.W. Stark (eds)., Western Spruce Budworm. U.S. Dep. Agric. For. Serv. Tech. B u l l . No. 1694. Coop. State Res. Serv. 198 pp. 1 62 Van Sickle, G.A., R.I. Alfaro and A.J. Thomson. 1983. Douglas-f i r height growth affected by western spruce budworm d e f o l i a t i o n . Can. J. For. Res. 13:445-450. Vetter, R.S. and T.C. Baker. 1983. Behavioral responses of male H e l i o t h i s virescens in a sustained-flight tunnel to combinations of seven compounds i d e n t i f i e d from female sex pheromone glands. J. Chem. Ecol. 9:747-759. Vick, K.W., J . Kvenburg, J.A. C o f f e l t and C. Steward. 1979. Investigation of sex pheromone traps for simultaneous detection of Indian meal moths and Angoumois grain moths. J. Econ. Entomol. 72:245-249. Wall, C. and J.N. Perry. 1978. Interactions between pheromone traps for the pea moth, Cydia nigricana (F.). Entomol. Exp. Appl. 24:155-162. Watts, S.B., ed. 1983. Forestry Handbook for B r i t i s h Columbia. 4th ed. The Forestry Undergraduate Society, University of B r i t i s h Columbia. Vancouver. 611 pp. Weatherston, J . , W.L. Roelofs, A. Comeau and C.J. Sanders. 1971. Studies of p h y s i o l o g i c a l l y active arthropod secretions. X. Sex pheromone of the eastern spruce budworm, Choristoneura fumife.rana (Lepidoptera:Tortricidae). Can. Ent. 103:1741-1747. Wellington, W.G. 1948. The l i g h t reactions of the spruce budworm. Can. Ent. 80:56-82A. Wellington, W.G. 1979. Insect d i s p e r s a l : a biometeorological perspective, pp. 104-108. i_n Rabb, R.L. and G.G. Kennedy (eds.), Movement of Highly Mobile Insects: Concepts and Methodology in Research. North Carolina State University, Raleigh. 456 pp. Wellington, W.G. and W.R. Henson. 1947. Notes on the e f f e c t s of physical factors on the spruce budworm, Choristoneura fumiferana (Clem.). Can. Ent. 79:168-170. Williams, C.B., J r . 1967. Spruce budworm damage symptoms related to r a d i a l growth of grand f i r , Douglas-fir, and Engelmann spruce. For. S c i . 13:274-285. Winer, B.J. 1971. S t a t i s t i c a l P r i n c i p l e s in Experimental Design. 2nd ed. McGraw-Hill Book Co., NY. 907 pp. Witzgall, P. and E. Priesner. 1984. Behavioral responses of Coleophora l a r i c e l l a male moths to synthetic sex-attractant, (Z)-5-decenol, in the f i e l d . Z. Ang. Ent. 98:15-33. 163 Wyman, J.A. 1979. Effect of trap design and sex attractant release rates on tomato pinworm catches. J . Econ. Entomol. 72:865-868. Zar, J.H. 1984. B i o s t a t i s t i c a l Analysis. Prentice H a l l , Inc., Englewood C l i f f s , N.J. 718 pp. 1 6 4 APPENDIX I. Age of the v i r g i n female vs trap catch The objective of this experiment was to see how age affected the attractiveness of v i r g i n female moths so that females of a standard age range could be used in trapping bioassays. Budworm larvae (L^-Lg) were co l l e c t e d by branch beating and reared on foliage in styrofoam cups. A newly emerged, v i r g i n female adult moth was placed in a screen cage inside each of f i v e double funnel traps which contained soapy water in the c o l l e c t i n g j a r ; another f i v e traps were baited with ALD bubblecaps (50 ug/d). The traps were spaced 25 m apart in completely randomized order across the Oregon Jack Creek valley and the catch was checked da i l y between 1430 and 1500 PST Mean catch in the female-baited traps peaked at four days from eclosion but da i l y catch in the ALD-baited traps followed the same pattern (Fig. 25). On any day, there was no s i g n i f i c a n t difference in mean catch between female- and ALD-baited traps ( t - t e s t , P ^ 0.05). This experiment ran from 28 July to 4 August 1983 when the budworm f l i g h t season was nearly over. The drop in catch was probably due to fewer male moths in the area, and not because the female became less a t t r a c t i v e , but i t i s d i f f i c u l t to say; the female remained at least as a t t r a c t i v e as the ALD over the entire eight days. In hindsight, I see that an unbaited trap would have served as a useful cont r o l . I concluded that v i r g i n females could be used in trapping bioassays from 2-6 d from eclosion. Fig. 25. The effect of age (days from eclosion) on the attractiveness of v i r g i n female western spruce budworm moths to conspecific male moths, as measured by trap catch in double funnel traps. Catch in traps baited with ALD (50 ug/d in a bubblecap lure) were included as a covariate. 166 APPENDIX I I . Pheromone-mediated b e h a v i o r - a d d i t i o n a l t a b l e s . T a b l e 3 3 . R e l a t i v e v a r i a b i l i t y o f l a b o r a t o r y , w i l d a n d l a b - w i l d p o p u l a t i o n s o f w e s t e r n s p r u c e b u d w o r m a d u l t m a l e s i n r e s p o n s e t o a r a n g e o f c o n c e n t r a t i o n s o f A L D a n d a v i r g i n f e m a l e . P O P . T R E A T M E N T C O E F F I C I E N T OF V A R I A T I O N FOR E A C H B E H A V I O R A L V A R I A B L E W i n g T a k e L o c k U p w i n d 1 m 1 . 5 m T o u c h L a n d C o p . / n f a n o f f o n f 1 i g h t WILD T O T A L 123 .4 33 . 3 8 6 96 . 2 1 10 . 1 1 1 4 . 6 1 1 5 . 5 1 1 5 . 5 2 1 7 . 4 L A B / W I L D 92 .6 31 .8 7 6 . 7 86 .4 88 . 2 9 3 9 9 . 3 1 0 0 . 9 184 . 5 L A B 52 . 4 36 .8 9 6 . 9 100 .6 106 .4 1 1 4 . 4 1 2 1 . 2 1 2 0 . 8 164 . 8 WILD F E M A L E 59 .2 18 .2 ' 22 . 2 32 . 3 4 0 . 2 6 3 . 7 7 0 7 0 1 4 5 . 4 L A B / W I L D 64 .8 16 .8 3 0 .4 2 0 . 3 2 5 . .2 2 8 . 6 3 5 . 5 3 8 . 5 9 4 . 2 LAB 37 . 2 17 .6 64 .4 74 . 8 72 . . 7 8 3 . 2 8 3 . 2 8 1 . 4 l O I . 9 WILD O . 5 ALD 38 . 2 21 . . 6 4 8 . 3 67 . . 2 8 1 . 2 7 0 7 0 7 0 L A B / W I L D 38 . 2 9 . 1 28 . 8 6 5 . . 5 6 5 . 5 7 8 . 8 7 8 . 8 8 6 . 7 1 2 8 . 8 LAB 1 1 . 1 13 . . 3 1 10 . 5 102 . 4 131 131 131 131 185 WILD 0 . 0 5 ALD 129 17 .6 5 5 . 9 8 5 . .4 105 . 6 1 0 5 . 6 105 . 6 1 0 5 . 7 L A B / W I L D 5 0 . .2 15 . 4 26 . 9 3 9 . 5 5 0 . 3 5 3 . 2 5 3 . 2 5 3 . 2 2 3 3 . 3 L A B 18 . 9 27 . , 3 4 6 . 5 5 4 . . 2 5 0 . 6 55 . 5 5 5 . 5 5 5 . 5 1 4 0 . 8 WILD 0 . 0 3 A L D 57 . .5 2 3 . 2 44 .4 5 0 . 6 54 . 1 54 . 1 54 . 1 54 . 1 2 5 3 . 3 L A B / W I L D 39 . 4 2 9 . 9 54 . 2 62 . . 7 7 1 . 3 8 5 . 1 8 5 . 5 8 5 . 5 L A B 27 6 31 . 1 102 . 1 102 , .4 106 . .5 125 125 125 2 1 4 WILD 0 . . 0 0 5 ALD 163 38 . 1 81 . 9 67 . 2 73 . 1 92 . 6 9 2 . 6 9 2 . 6 L A B / W I L D 92 . 5 54 . 8 6 5 . 5 8 5 . 5 8 5 . 5 8 5 . 5 l O O . 7 8 5 . 5 L A B 5 0 . 6 3 5 , 6 9 6 . 7 1 1 2 . 7 1 2 6 . .4 1 2 6 . 4 1 1 9 . 2 1 1 8 . 8 1 1 3 . 8 WILD 0 . 0 0 0 5 ALD 163 8 5 9 2 5 3 . 3 2 5 3 . 3 2 5 3 . .3 2 5 3 . 3 2 5 3 . 3 2 5 3 . 3 L A B / W I L D 130 4 2 . 8 1 18 .7 1 18 . 7 107 107 128 . 8 1 0 0 . 7 2 3 3 . 3 L A B 9 2 . . 8 6 6 . 5 107 107 107 1 2 8 . 8 184 184 2 3 3 . 3 WILD 0 . 0 0 0 0 5 ALD 2 5 3 28 . 3 96 . 4 1 1 7 . 8 163 . 3 163 . 3 163 . 3 163 . 3 2 5 3 . 3 L A B / W I L D 2 3 3 54 . 2 2 1 3 2 1 3 2 1 3 2 1 3 2 1 3 2 1 3 L A B 128 . 8 6 6 5 151 151 151 151 151 151 T a b l e 34. The temporal responses of western s p r u c e budworm a d u l t males ( l a b o r a t o r y ) to v a r i o u s b l e n d s of 0.05% ALD. 0.5% AC, and 0.5% OH, In a wind t u n n e l . Responses were compared w i t h those to a v i r g i n female and a blan k c o n t r o l l u r e . Due to the small number of r e s p o n d e r s , d a t a from AC, OH and the CONTROL were not I n c l u d e d m the ANOVA or means t e s t s , except f o r the v a r i a b l e of R-TO. A l l components were f o r m u l a t e d In 5 X 3 mm pvc r o d s . TREATMENT 1 2 3 L MEAN TIME INTERVAL ( s ) » n R-WF n R-TO n TO-LO n STAT.ZZ n T-L n R-L n TO-L FEMALE 20 6 .0 25 28 .8 16 ALD+AC+OH 20 16 .6 24 23 .9 15 ALD+AC 24 9 . 1 28 28 0 21 ALD+OH 18 8 .6 24 13 .0 17 ALD 18 1 1 . 4 29 21 1 20 AC 2 6 .0 1 1 41 .3 1 OH 1 2 .0 1 1 37 6 1 CONTROL 2 67 .0 3 .3 15 1 .3 13 2 .9 13 6 1 . 2 13 30 7 5. 3 15 3 .0 14 1 1 .7 14 62 9 14 45 0 4 6 19 3 .0 19 4 .0 19 56 .4 19 31 5 4 . 1 13 1 .3 1 1 8 2 1 1 49 5 1 1 39. 1 3 .2 17 4 . 1 16 6 . 7 16 62 . 1 16 43 8 1 1 .0 1 0 .0 1 0. .0 1 155. .0 1 37 .0 2 .0 1 1 .0 1 0 .0 1 33 .0 1 2 1 0 GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc l u r e s i n d i c a t e d t h a t the ALD l u r e s c o n t a i n e d some OH and the AC l u r e s c o n t a i n e d b o t h ALD and OH contaminants. Means w i t h i n columns are not s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, « = 0.05. Data t r a n s f o r m e d by l o g (y+1). R = R e l e a s e on p l a t f o r m ; WF « I n i t i a t i o n of wing-fanning; TO = Take o f f ; LO = Lock-on ( I n i t i a t i o n of z i g - z a g f l i g h t ) ; STAT.ZZ = D u r a t i o n of s t a t i o n a r y z i g - z a g f l i g h t ; T = Touching l u r e cage; L = l a n d i n g a t l u r e cage. T a b l e 35. The temporal responses of western spruce budworm a d u l t mates ( w i l d ) to v a r i o u s b l e n d s of 0.05% ALD, 0.5% AC, and 0.5% OH In a wind t u n n e l . Responses were compared w i t h those to a v i r g i n female and a b l a n k c o n t r o l l u r e . Due to the small number of r e s p o n d e r s , d a t a from AC. OH and the CONTROL were not I n c l u d e d i n ANOVA or means t e s t s , except f o r the v a r i a b l e of R-TO. A l l components were f o r m u l a t e d In 5 X 3 mm pvc r o d s . TREATMENT MEAN TIME INTERVAL (s ,2,3 n R-WF n R-TO n TO- -LO n STAT.ZZ n T -L n R--L n TO-L FEMALE 25 10.0 33 23.3 b 20 4 .0 20 3.2 b 16 2 .4 16 37 8 b 16 28.9 ALD+AC+OH 16 20. 2 26 29.7 b 14 6 . 3 12 3.0 ab 7 3 . 3 8 78 .0 ab 8 38 . 3 ALD+AC 7 17.0 27 29.9 ab 14 3 6 14 1.9 b 1 1 4 . 2 11 60 . 7 ab 1 1 26.8 ALD+OH 3 7.0 20 28.8 ab 5 4 . 2 4 9.8 a 3 2 .0 3 98 .0 a 3 32 . 7 ALD 9 18.9 26 20.7 ab 6 5 .0 6 0.8 b 5 0 .6 5 38 .6 b 5 29.0 AC 15 53. 1 a 1 2 .0 1 0.0 1 4 .0 1 74 .O 1 31.0 OH 14 58.3 ab CONTROL 13 40.4 ab GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc l u r e s i n d i c a t e d t h a t the ALD l u r e s c o n t a i n e d some OH and the AC l u r e s c o n t a i n e d both ALD and OH contaminants. Means w i t h i n columns f o l l o w e d by d i f f e r e n t l e t t e r ( s ) a r e s i g n i f i c a n t l y d i f f e r e n t . <* = 0.05. Data t r a n s f o r m e d by l o g (y + 1). ANOVA and Newman-Keuls, R = R e l e a s e on p l a t f o r m ; WF = I n i t i a t i o n of w i n g - f a n n i n g : TO = Take o f f ; LO = Lock-on ( I n i t i a t i o n of z i g - z a g f l i g h t ) ; STAT.ZZ = D u r a t i o n of s t a t i o n a r y z i g - z a g f l i g h t ; T = Touching l u r e cage; L = l a n d i n g at l u r e cage. Table 36. The net ground speed of f l i g h t of adult male western spruce budworms (laboratory) 1n response to blends of 0.05% ALD, 0.5% AC, and 0.5% DH 1n a wind tunnel. Speed was measured in three sections of the tunnel and averaged from the s t a r t of stationary zig-zag (LO-T) and the s t a r t of upwind f l i g h t (UF-T). A l l components were formulated 1n 5 X 3 mm pvc rods. TREATMENT MEAN NET GROUND SPEED OF FLIGHT (cm/s) 2 n 2m--1m 3 n 1m-0. , 5m n 0. 5m-T n UF -T n LO--T FEMALE 14 17, .0 12 15, ,9 12 8 . 1 12 12. 5 12 1 1 .7 ALD+AC+OH 14 12 , .0 14 11 , . 7 14 8 .9 14 10. 2 14 9 .6 ALD+AC 18 12. , 1 18 14 . 8 18 10 .9 18 10. 5 18 9, ,4 ALD+OH 13 14. , 1 11 11 . , 1 1 1 9 . 1 1 1 10. 2 11 9 .8 ALD 17 14. 2 16 12. ,7 16 8 . 4 16 10. 1 16 9. , 2 AC 1 16, 7 1 5. 0 1 5 .0 1 7 . 7 1 7. , 7 OH 1 20. 0 1 7. 1 1 8 .3 1 1 1 . 1 1 10. ,5 1 GLC a n a l y s i s of v o l a t i l e s c o l l e c t e d from pvc lures i n d i c a t e d that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. Means within columns not s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls, « = 0.05. Data transformed by log (y+1). Distance from the pheromone source. Table 37. The net ground speed of f l i g h t of adult male western spruce budworm (wild) i n response to blends of 0.05% ALD, 0.5% AC. and 0.5% OH in a wind tunnel Speed was measured in three sections of the tunnel and averaged from the s t a r t of stationary zig-zag (LO-T) and the s t a r t of upwind f l i g h t (UF-T). A l l components were formulated In 5 X 3 mm pvc rods. TREATMENT MEAN NET GROUND SPEED OF FLIGHT (cm/s) 3 n 2m-1m n 1m-0.5m n 0.5m-T n UF-T n LO-T FEMALE 19 21 .8 16 23 .8 16 14 . 5 16 14 . 6 16 12 . 8 ALD+AC+OH 1 1 23 .3 9 1 1 .4 8 8 .7 8 10 .4 8 9 . 2 ALD+AC 14 21 .4 1 1 19 .6 1 1 8 .3 1 1 12. .2 1 1 10, , 7 ALD+OH 4 10 .6 3 9. . 2 3 13, .5 3 8 .9 3 7. . 3 ALD 6 21 . .6 6 1 1 . . 5 6 12. .9 6 12 . 5 6 1 1 . 4 AC 1 6 . 7 1 8 .3 1 12 .5 1 8 .0 1 8 .0 1 GLC an a l y s i s of v o l a t i l e s c o l l e c t e d from pvc lures indicated that the ALD lures contained some OH and the AC lures contained both ALD and OH contaminants. 2 Means within columns are not s i g n i f i c a n t l y d i f f e r e n t . ANOVA and Newman-Keuls, cx = 0.05. Data transformed by log (y+1). 3 Distance from the pheromone source. 1 7 2 Table 38. The e f f e c t of adding 0.0005-0.005% 14:ALD to 0.05% ALD, on the cat c h of w i l d western spruce budworm male moths i n t r i a n g u l a r s t i c k y t r a p s . A l l components were formulated i n 5 X 3 mm pvc rods. The t r a p s were set out i n a t i m e - r e p l i c a t e d l a t i n square design (7 X 7)(24-26 J u l y 1984). Treatment Trap c a t c h (n=7) Mean S.E. ALD(0.05%) ALD(0.05%) + 14:ALD(0.0005%) ALD(0.05%) + 14:ALD(0.005%) 14:ALD(0.005%) V i r g i n female 14:ALD(0.0005%) 24.4 48. 1 55.0 25. 1 55. 1 14.6 7.9 b 7.6 a 3.8 b 9.4 a 3.8 a 3.8 c C o n t r o l 1 .1 0.4 d Means f o l l o w e d by the same l e t t e r are not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (<*= 0.05). A n a l y s i s performed on transformed data ( l o g ( y + l ) ) 1 7 3 Table 39. The effect of adding 0.005% 14:AC to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (6 X 6)(24-27 July 1984). Treatment Trap catch (n=6) Mean S.E. ALD(0.05%) + 14:AC(0.005%) ALD(0.05%) + ALD(0.05%) ALD(0.05%) Vir g i n female 14:AC(0.005%) 41 .3 43.0 42.8 18.2 0.6 12.6 a 9.1 a 9.8 a 3.8 a 0.4 b Control 0.0 0.0 b Means followed by the same l e t t e r are not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (<* = 0.05). Analysis performed on transformed data (log(y+1)) 1 7 4 Table 40. The effect of adding 0.0005% 14:ALD, 0.005% AC, or both, to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. the traps were set out in a time-replicated l a t i n square design (8 X 8) (27-31 July 1984). Treatment Trap catch (n=8) Mean 1 S.E. ALD(0.05%) + AC(0.005%) + 14:ALD(0.0005%) 34.1 4.9 a ALD(0.05%) + AC(0.005%) 32.9 3.5 a ALD(0.05%) + 14:ALD(0.0005%) 28.6 4.9 a ALD(0.05%) 25.5 3.5 a V i r g i n female 25.4 5.7 a 14:ALD(0.0005%) 7.8 1 .8 b AC(0.005%) + 14:ALD(0.0005%) 2.9 0.7 c Control 0.3 0.2 d Means followed by the same l e t t e r are not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (c*= 0.05). Analysis performed on transformed data (log(y+l)) 1 7 5 Table 41. The effect of adding 0.005% AC, 0.005% 14:AC, or both, to 0.05% ALD, on the catch of wild western spruce budworm male moths in triangular sticky traps. A l l components were formulated in 5 X 3 mm pvc rods. The traps were set out in a time-replicated l a t i n square design (6 X 6)(27-30 July 1984). Treatment Trap catch (n=6) Mean S.E. ALD(0.05%) + AC(0.005%) + 14:AC(0.005%) ALD(0.05%) + AC(0.005%) ALD(0.05%) + 14:AC(0.005%) ALD(0.05%) V i r g i n female Control 24.8 3 5 . 8 15.3 17.7 6.7 0.2 8.5 a 4.1 a 2.9 a 2 . 0 b 4.1 a 0.2 c Means followed by the same l e t t e r are not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (<* = 0.05). Analysis performed on transformed data (log(y+1)) 1 7 6 T a b l e 42. The e f f e c t of ad d i n g 0.005% AC, 0.005% OH, 0.005% 14:AC, and 0.0005% 14:ALD t o 0.05% ALD, on the c a t c h of w i l d w e s t e r n s p r u c e budworm male moths i n t r i a n g u l a r s t i c k y t r a p s . A l l components were f o r m u l a t e d i n 5 X 3 pvc r o d s . The t r a p s were s e t out i n a t i m e - r e p l i c a t e d l a t i n square d e s i g n (11 X 1 1 )(30 J u l y - 13 August 1984). Treatment Trap c a t c h ( n - H ) Mean 1 S.E. ALD(0.05%) + AC(0.005%) + OH(0.005%) + 14:AC (0 .005%) + 14:ALD(0.0005%) 18.1 12.7 ALD(0.05%) + AC(0.005%) + OH(0.005%) + 14:ALD(0.0005) 25.0 14.4 ALD(0.05%) + AC(0.005%) + OH(0.005%) + 14:AC(0.005%) 21.1 11.8 ALD(0.05%) + AC(0.005%) + OH(0.005%) 25.6 9.6 ALD(0.05%) + AC(0.005%) + 14:ALD(0.0005%) 26.7 14.1 ALD(0.05%) + AC(0.005%) + 14:AC(0.005%) 21.4 12.2 ALD(0.05%) + OH(0.005%) + 14:AC(0.005%) 24. 1 16.5 ALD(0.05%) + AC(0.005%) 20.0 12.4 ALD(0.05%) + 14:ALD(0.0005%) 24.9 15.0 ALD(0.05%) 24.0 1 1.9 14:ALD(0.0005%) 1.8 1.8 Means f o l l o w e d by the same l e t t e r a r e not s i g n i f i c a n t l y d i f f e r e n t , ANOVA & Newman-Keuls (cx = 0.05). A n a l y s i s performed on t r a n s f o r m e d d a t a ( l o g ( y + l ) ) 1 7 7 APPENDIX I I I . Diurnal p e r i o d i c i t y of male moth response to sex pheromone. Western spruce budworm male moths were caught in pheromone traps during midday in the summer of 1982. This appeared to c o n f l i c t with Shepherd (1979) who found that males responded between 1800 and 2400. Therefore, in July 1983, the diurnal p e r i o d i c i t y of the budworm in the Oregon Jack Creek valley was monitored over a three day period. Six sticky traps, three baited with a v i r g i n female 2-6 d from eclosion, and three baited with a crude blend of E/z-11-tetradecenal in three micropipettes in a glass v i a l , were set out across v a l l e y in completely randomized order. The sticky traps were replaced whenever the catch exceeded 30 moths and the catch was t a l l i e d for each trap every hour for three days. The p e r i o d i c i t y of male response i s shown in F i g . 26. Moths were caught from 800 to 2400 PST but 65% of the moths were caught between 1800 and 2100. The peak response occurred about one hour e a r l i e r than that reported by Shepherd (1979) and Liebhold and Volney (1984b). Liebhold and Volney (1984b) found that western spruce budworm males respond to pheromone e a r l i e r in the day when temperatures are cool. The p e r i o d i c i t y of catch in the female-baited traps p a r a l l e l e d that of the synthetic-baited traps. The female budworm has been observed to " c a l l " from 1800 to 600, a much Fig. 26. Diurnal periodicity of adult male western spruce budworm response to virgin females (4-6 days from eclosion) and to synthetic pheromone (three 1 ul micropipettes of a crude blend of E/Z 11-tetradecenal in a 2 ml glass v i a l ) as £ measured in hourly catches in triangular sticky traps. Mean oo trap catch/hour is the total of three traps/treatment/hour, averaged over three nights (18-21 July, 1983). The arrow designates sunset (PST). 1 7 9 longer period than that recorded for the male's response (Liebhold and Volney 1984b). These results agree with those of others (Shepherd 1979; Liebhold and Volney 1984b) who suggested that mating p e r i o d i c i t y i s determined by the male's response and not the times of female c a l l i n g . APPENDIX IV. Monitoring with pheromone traps - additional tables and figures. 181 Fig. 27. The relationship between the mean number of larvae/three branches/plot in the lower crown (n =50 trees/plot) and the number of larvae/m^ foliage/plot in the mid-crown (n = 25 trees/plot). A. 1984, B. 1985. 1 8 2 Fig. 28. The relationship between the mean number of larvae/three branches/plot in the lower crown (n = 50 trees/plot) and the number of larvae/100 new shoots/plot in the mid-crown (n = 25 trees/plot). A. 1984, B. 1985. Table 43. C o r r e l a t i o n c o e f f i c i e n t s between to t a l season's catch/plot (n = in various pheromone trap systems in 1984 and l a r v a l d e n s i t y / p l o t in 1984. were b a i t e d with ALD. 1 tr a p / p l o t ) A l l traps Trap system A l l p l o t s included ' Plot 12 excluded Beat L/m f o l . L/100 s. Beat L/m'Tol. L/100 s. (n=15) (n=9) (n=9) (n=14) (n=8) (n=8) Sticky, 0 .05% M 0 . 12 0 .00 -0, .07 0 . 10 0, . 10 -0. .07 Uni-trap, 0.05% M 0, . 18 -0, . 13 -0. .22 0. .43 0, .27 -0. .22 Sticky, 0 .05% NM -0. .35 -0. . 17 -0, .06 -0. .67 * -0. .75 ** -0. .60 Uni-trap, 0.05% NM 0. .09 -0. . 12 -0. , 14 0. , 17 0, .04 0. .01 Sti c k y , 0, .0005% M 0. , 16 0. ,50 0. 28 0. . 16" 0. .55 0. .31 Uni-trap, 0.0005% M 0. 05 -0. ,07 -0. 20 0. ,07 0. .02 -0, . 13 Sticky, 0. .0005% NM -0. 01 -0. ,01 -0. 19 -0. ,04 -0. .01 -0. ,21 Uni-trap, 0.0005% NM -0. 08 -0. 49 -0. 58 -0. 04 -0. 42 -0. ,52 Beat = No. of larvae/three branches; L/m 2fol = No. of 1arvae/m2 f o l i a g e L/100 s. = No. of larvae/100 new shoots; M = Maintained; NM = Non-maintained. * denotes s i g n i f i c a n c e at P ^ 0.10; ** denotes s i g n i f i c a n c e at £ < : 0 . 0 5 . Table 44. Co r r e l a t i o n c o e f f i c i e n t s between the mean t o t a l season's catch/plot (n=5 tra p s / p l o t ) in 1984 and l a r v a l density/plot in 1984. Traps were baited with 0.05% ALD. Trap system Al 1 p l o t s included ( n - S ) 1 - 2 Plot 12 excluded (n=4) Beat L/m 2fol . L/100 s. Beat L/m2 f o l . L/100 s. St i c k y , 0.05% NM 0.49 0.31 0.41 0.00 -0.14 -0.01 Uni-trap, 0.05% NM 0.53 0.73 0.69 0.94 * 0.97 ** 0.95 ** Beat = No. of larvae/three branches; L/m f o l = No. of 1arvae/m 2foliage L/100 s. = No. of larvae/100 new shoots; M = Maintained; NM = Nonmaintained. * denotes s i g n i f i c a n c e at 0.10; ** denotes s i g n i f i c a n c e at £4 0.05. Table 45. C o r r e l a t i o n c o e f f i c i e n t s between total season's catch/plot (n = 1 tr a p / p l o t ) in various pheromone trap systems in 1984 and la r v a l d e n s i t y / p l o t in 1985. A l l traps were ba i t e d with ALD. Trap system A l l p l o t s included 1» 2 Plot 12 excluded Beat L/m f o l . L/100 s. Beat L/m f o l . L/100 s. (n=15) (n=10) (n=10) (n=14) (n=9) (n=9) St i c k y , 0 .05% M 0 .45 * 0, .39 0, .55 * 0. .46 * 0, .41 0, .59 * Uni-trap. 0.05% M 0, ,44 * 0. . 18 0. . 26 0. ,67 ** 0. .58 * 0. .75 ** S t i c k y , 0 .05% NM -0. ,47 * -0. .41 -o. 37 -0. 74 * * -0. ,70 -0. 69 Uni-trap, 0.05% NM 0. , 27 0. , 1 1 0. 24 0. 34 0. 25 0. .40 S t i c k y , 0. .0005% M 0. 22 0. 46 0. 42 0. 22 0. 47 0. 43 Uni-trap. 0.0005% M 0. 23 0. 33 0. 43 0. 26 0. ,42 0. ,53 S t i c k y , 0. ,0005% NM 0. 27 0. 22 0. 25 0. 27 0. 22 0. 25 Uni-trap, 0.0005% NM 0. 06 -0. 25 -0. 13 0. 10 -0. 19 -0. 05 1 Beat = No. of larvae/three branches; L/m f o l = No. of larvae/m f o l i a g e L/100 s. = No. of larvae/100 new shoots; M = Maintained; NM = Nonmaintained. 2 * denotes s i g n i f i c a n c e at P ^0.10; ** denotes s i g n i f i c a n c e at P <0.05. Table 46. Correlation coefficients between the mean total season's catch/plot (n=5 traps/plot) in 1984 and larval density/plot in 1985. Traps were baited with 0.05% ALD. Trap system Al 1 plots included (n-3) 2 Plot 12 excluded (n=4) Beat L/m 2fol. L/100 s. Beat L/m 2fol . L/100 s. Sticky, 0.05% NM 0.35 0. 24 0.36 -0. 10 -0. 14 -0.08 Uni-trap, 0.05% NM 0.52 0.58 0.31 0.70 0.70 0.42 Beat = No. of larvae/three branches; L/m fol = No. of larvae/m foliage L/100 s. = No. of larvae/100 new shoots; M = Maintained; NM = Nonmaintained. No correlation was significant, P<;0.10. 1 8 7 B. a z § 400 -300 -200 -100 -o - | — r — n — i — i — i — i — i — i — i — r 11 13 13 17 19 21 23 29 27 29 31 July T 1 1 1 r 8 10 12 14 16 18 20 22 August F i g . 29. S e a s o n a l p r o f i l e o f t r a p c a t c h o f t h e w e s t e r n s p r u c e budworm. The t o t a l c a t c h i n e i g h t d i f f e r e n t p h e r o m o n e - b a i t e d t r a p s was t a l l i e d e v e r y two d a y s t h r o u g h o u t t h e 1984 f l i g h t s e a s o n . A. P l o t 1; B. P l o t 2. 1 8 8 B a I a I z 500 - i -400 -500 200 -100 -PLOT 3 O.J.CREEK o i — i — i — r 8 10 12 14 16 18 20 22 24 26 28 30 1 3 5 7 9 11 13 15 17 19 21 23 a I a z I i 500 400 -300 -200 100 -I I I I I I I 1 i I 1 I I I I I I I I I 1 I 8 10 12 14 16 18 20 22 24 26 28 30 1 3 5 7 9 11 13 15 17 19 21 23 July August F i g . 30. Seasonal p r o f i l e of tr a p catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plo t 3; B. Plot 4. 500 B. Fig. 31. Seasonal p r o f i l e of trap catch of the western spruce budworm. The total catch in eight different pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 5; B. Plot 6. 1 9 0 300 11 13 15 17 19 21 23 25 27 29 31 2 4 6 8 10 12 14 16 IB 20 22 J u l y August F i g . 32. Seasonal p r o f i l e of trap catch of the western spruce budworm. The t o t a l catch in eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Pl o t 7; B. Plot 8. 1 9 1 SOO 500 11 13 15 17 19 21 23 25 27 29 31 2 4 6 8 10 12 14 16 18 20 22 July August Fig. 33. Seasonal profile of trap catch of the western spruce budworm. The total catch in eight different pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 9; B. Plot 10. 1 9 2 500 B. PLOT 12 OJ.CREEK T — I — I — T 8 10 12 14 IS 18 20 22 24 26 28 30 1 3 5 7 9 11 13 15 17 19 21 23 J u l y August Fig. 34. Seasonal profile of trap catch of the western spruce budworm. The total catch in eight different pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 11; B. Plot 12. 1 9 3 a a I c X 400 -300 -200 -100 -B. PLOT 14 O.J.CREEK -1—I—I—I—I—I—I—I—I—I—I—I—I—I—r 8 10 12 14 16 18 20 22 24 26 28 30 1 3 S 7 J u l y - i — i — i — i — i — i — r 9 11 13 13 17 19 21 23 August Fig. 35. Seasonal profile of trap catch of the western spruce budworm. The total catch in eight different pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. A. Plot 13; B. Plot 14. 194 500 8 10 12 14 16 18 20 22 24 26 28 30 1 3 5 7 9 11 13 13 17 19 21 23 July August F i g . 36. A. Seasonal p r o f i l e of trap catch of the western spruce budworm in p l o t 15. The t o t a l catch i n eight d i f f e r e n t pheromone-baited traps was t a l l i e d every two days throughout the 1984 f l i g h t season. B. Seasonal temperature p r o f i l e in 1984; the temperature was monitored with a hygrothermograph inside a Stevenson screen located at about 850 m e l e v a t i o n in the Oregon Jack Creek v a l l e y . 1 9 5 APPENDIX V. Mark-release-recapture study Introduction Mark-release-recapture (m-r-r) studies have been used to estimate the density (Ramaswamy e_t a l . 1983) and average d a i l y loss to mortality and dispersal (Sanders 1983), of male spruce budworm moths. Recapture rates have ranged from 0-100% (Ennis and Charlebois 1979; M i l l e r and McDougall 1973; Ramaswamy et a l . 1983, Sanders 1983). The objectives of this study were to: 1) estimate the proportion of male moths in a stand that were captured by pheromone traps; and 2) to determine the r e l a t i v e frequency of up- and down- valley dispersal of males. Methods and Materials F i e l d releases Male budworm larvae and pupae were co l l e c t e d by branch beating and reared on foliage in styrofoam cups. A large percentage of the co l l e c t e d budworms were paras i t i z e d or died from unknown causes so that adult males were also trapped l i v e in Uni-traps, baited with 0.05% ALD but no dichlorvos, and then marked and released l a t e r the same evening. The moths were marked with Day-glo fluorescent powder puffed from a squeeze b o t t l e . The live-trapped moths were counted as they flew from the bucket of the Uni-trap in which they were caught; moths that dropped straight to the ground were not counted. A l l traps were baited with 0.05% ALD. Moths were released between 1900 and 2000 PST on eight d i f f e r e n t evenings. The following morning, moths were removed from the Uni-traps and 1 9 6 sticky traps were c o l l e c t e d . The moths were later counted and examined under a b l a c k l i g h t . The traps were set out in four d i f f e r e n t designs. A l l of the traps were baited with 0.05% ALD. In the f i r s t * design, ten Uni-traps were l a i d out across valley in two l i n e s of 5 traps each; the two li n e s were 100 m apart. A t o t a l of 145 reared moths were marked and released onto 2 m t a l l , wooden platforms placed 25 m (red), 50 m (blue), and 75 m (green) down-valley from the middle trap of the up-valley trap l i n e ; about 50 moths were released at each p o s i t i o n . In the second design, a t o t a l of 24 traps, 12 sticky and 12 Uni-traps, were alternated 25 m apart in a 5 X 5 grid , and moths were released from the center of the g r i d . A t o t a l of 243 reared moths and 569 live-trapped moths were released over three evenings. The t h i r d design d i f f e r e d from the second only by replacing the Uni-traps with sticky traps; i.e. a l l 24 traps were sticky traps. A t o t a l of 804 l i v e trapped moths were released over three d i f f e r e n t evenings. In the fourth design, four rows of sticky traps, 5 traps/row, were l a i d across valley at distances of 50 and 100 m up-valley and down-valley from a central release point. A t o t a l of 150 live-trapped moths were released on one evening. Wind tunnel tests I had intended to test for the possible effects of the fluorescent powder on the male moth's antennal response and f l i g h t in the wind tunnel, prior to the f i e l d season. Unfortunately, there were no laboratory moths available six months pr i o r to the 1984 f i e l d season because the colony had 1 9 7 been wiped out by an infection of Nosema sp. Therefore, these tests were conducted after the m-r-r f i e l d work. The EAG amplitude in response to 0.5% and 0.05% ALD, was measured for nine male moths that had been dusted with fluorescent powder and compared with the amplitude of nine undusted control moths. Four treatments were compared for response to pheromone in the wind tunnel: 1) moths that had been placed in the bucket of a Uni-trap baited with 0.05% ALD, and suspended in the wind tunnel for 45 min, and then dusted with fluorescent powder; 2) moths dusted with fluorescent powder only; 3) moths kept inside a Uni-trap only; and 4) moths neither dusted nor kept inside a trap (controls). Moths were released fiv e at a time, 1.5 m downwind from a 0.05% ALD lure, and were observed for the usual behaviors. Each replicate consisted of ten moths and each treatment was replicated fi v e times in a randomized complete block design. Results and Discussion Of a t o t a l of 388 reared moths and 1523 live-trapped moths released, only three were caught (about 0.2%) and one of these was caught in a trap that was part of a d i f f e r e n t experiment about 200 m down-valley (Table 47). The very low recapture rate was surprising u n t i l the wind tunnel study was conducted. The percentages of moths wingfanning, locking-on and reaching the lure, and displaying copulatory behavior, were s i g n i f i c a n t l y 1 9 8 Table 47. Summary of mark-release-recapture experiments with the western spruce budworm in the Oregon Jack Creek v a l l e y . Design 1 used ten Uni-traps; design 2 used a g r i d of 12 Uni-traps and 12 sticky traps; designs 3 used a grid of 24 sticky traps.; and design 4 used four l i n e s of five sticky traps each. A l l traps were baited with 0.05% ALD. Design No. T r i a l No. No. males released No. males caught Reared Live-trap Marked Wild 1 1 1 45 2 1 200 2 43 3 0 3 1 0 2 0 3 0 4 1 0 Totals 388 0 0 — 0 0 1059 215 0 2177 354 1 2787 252 0 1650 221 1* 1 036 331 1* 1 128 150 0 1 367 1523 3 1 1 204 * This male was caught in a trap 200 m downwind in another experiment. 1 9 9 reduced when the males had been either dusted with powder, pre-exposed to pheromone in the Uni-trap, or both; the percentages able to f l y were not s i g n i f i c a n t l y d i f f e r e n t (Table 48). The wind tunnel results appeared to explain why so few moths were caught in the m-r-r experiments: the marked, dusted moths were simply not very responsive to pheromone but the reasons are not unknown. The EAG amplitude was not s i g n i f i c a n t l y d i f f e r e n t between dusted and undusted moths (Table 49) which suggests that antennal s e n s i t i v i t y to pheromone was not affected by the fluorescent powder. Perhaps the moths' sight was adversely affected by the dust and they were unable to use optomotor cues required in their response to pheromone. Ramaswamy et a l . (1983) also used Day-glo powder in their m-r-r studies with the spruce budworm but they had recapture rates of 15-22%. It i s possible that I applied more powder to my moths than they did to t h e i r s . The reduced response in the moths l e f t in a Uni-trap was probably due to habituation from the pre-exposure to pheromone in the trap. Future mark-release-recapture studies of the western spruce budworm should use dyes (e.£. Sanders 1 983) rather than fluorescent powder, and should use reared moths rather than live-trapped moths. The hypothesis of increased competition from v i r g i n females could be tested by comparing the recapture rates in heavy and l i g h t i n f e s t a t i o n s . 200 T a b l e 48. The e f f e c t of f l u o r e s c e n t powder (dusted) with or without p r e v i o u s capture i n a pheromone-baited U n i - t r a p , on response of western spruce budworm male moths to 0.05% ALD i n a wind t u n n e l . Treatment Mean percentage response 1 (n = 5 ) 2 Wing fan Take-off Lock-on Land Cop Able to f l y C o n t r o l 84 a 82 24 a 20 23 a 69 Dusted 42 b 49 4 b 2 0 b 66 Pre-trapped 38 b 61 4 b 4 2 b 55 Dusted and Pre-trapped 34 b 29 0 b 0 0 b 66 Means f o l l o w e d by d i f f e r e n t l e t t e r s are s i g n i f i c a n t l y d i f f e r e n t , ANOVA and Newman-Keuls (c* = 0.05). Data transformed by a r c s i n J~y~. Each r e p l i c a t e c o n s i s t e d of 10 moths, so 50 moths were flown per treatment. 201 Table 49. Effe c t of fluorescent powder (dusted) on the antennal amplitude of western spruce budworm in response to ALD, as measured by the electroantennogram technique. Treatment n Mean amplitude (mv)1 0.5% ALD 0.05% ALD Dusted 9 1.04 0.77 Not dusted 9 1.17 0.82 Means within a given concentration are not s i g n i f i c a n t l y d i f f e r e n t , Student's t - t e s t (P ^  0.05). 

Cite

Citation Scheme:

        

Citations by CSL (citeproc-js)

Usage Statistics

Share

Embed

Customize your widget with the following options, then copy and paste the code below into the HTML of your page to embed this item in your website.
                        
                            <div id="ubcOpenCollectionsWidgetDisplay">
                            <script id="ubcOpenCollectionsWidget"
                            src="{[{embed.src}]}"
                            data-item="{[{embed.item}]}"
                            data-collection="{[{embed.collection}]}"
                            data-metadata="{[{embed.showMetadata}]}"
                            data-width="{[{embed.width}]}"
                            async >
                            </script>
                            </div>
                        
                    
IIIF logo Our image viewer uses the IIIF 2.0 standard. To load this item in other compatible viewers, use this url:
http://iiif.library.ubc.ca/presentation/dsp.831.1-0302137/manifest

Comment

Related Items