UBC Theses and Dissertations

UBC Theses Logo

UBC Theses and Dissertations

The feasibility of a Floating Vertical Raceway for salmon smolt production in British Columbia Neufeld, Trev 1991

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

Item Metadata

Download

Media
831-UBC_1991_A6_7 N48.pdf [ 3.43MB ]
Metadata
JSON: 831-1.0058866.json
JSON-LD: 831-1.0058866-ld.json
RDF/XML (Pretty): 831-1.0058866-rdf.xml
RDF/JSON: 831-1.0058866-rdf.json
Turtle: 831-1.0058866-turtle.txt
N-Triples: 831-1.0058866-rdf-ntriples.txt
Original Record: 831-1.0058866-source.json
Full Text
831-1.0058866-fulltext.txt
Citation
831-1.0058866.ris

Full Text

FEASIBILITY OF A FLOATING VERTICAL RACEWAY FOR SALMON SMOLT PRODUCTION IN BRITISH COLUMBIA by TREV NEUFELD B . S c , The U n i v e r s i t y o f B r i t i s h Columbia, 1983 A THESIS SUBMITTED IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF MASTER OF SCIENCE i n THE FACULTY OF GRADUATE STUDIES (Department of Bio-Resource Engineering) We accept t h i s t h e s i s as conforming t o the r e q u i r e d standard THE UNIVERSITY OF BRITISH COLUMBIA September 1991 ° Trev N e u f e l d , 1991 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 The University of British Columbia Vancouver, Canada Date DE-6 (2/88) ABSTRACT In B r i t i s h Columbia the F l o a t i n g V e r t i c a l Raceway (FVR) system has o n l y r e c e n t l y been i n t r o d u c e d as a t e c h n i q u e t o produce low c o s t salmonid smolts. A FVR i s c o n s t r u c t e d of s y n t h e t i c rubber s h e e t i n g and may be assembled a t , and/or w i t h i n , an e x i s t i n g o f f - s h o r e marine net pen. The FVR i s f i l l e d w i t h freshwater or v a r y i n g p r o p o r t i o n s of f r e s h w a t e r / s a l t w a t e r and thereby f l o a t s on the denser s a l t w a t e r . Mixed r e s u l t s have shown t h a t i n c o n s i s t e n t and u n r e l i a b l e d e s igns can prevent s u c c e s s f u l a p p l i c a t i o n of the FVR systems. The d e s i g n problems are g e n e r a l l y a s s o c i a t e d w i t h s t a b i l i t y and t u r g i d i t y of the raceway. In t h i s study a computer generated spreadsheet s i m u l a t i o n (CGSS) was developed t o p r e d i c t the t e c h n i c a l and economic f e a s i b i l i t y o f 3 FVR s c e n a r i o s through s e v e r a l p r o d u c t i o n c y c l e s . The program p r o v i d e s a t o o l t o a s s i s t producers, i n v e s t o r s and banks t o assess the t e c h n i c a l and economic f e a s i b i l i t y o f a FVR system. An a n a l y s i s of the CGSS behaviour p r o v i d e s v a l u a b l e i n s i g h t s f o r p r o s p e c t i v e - o p e r a t o r s and farmers. R e s u l t s i n d i c a t e t h a t f o r a FVR w i t h a volume of 100 m3 i n f l u e n t water flow r a t e s o f 150, 300 and 600 1/min w i l l i n c u r oxygen d e f i c i e n c i e s a t 160, 180 and 210 days i n t o a p r o d u c t i o n c y c l e , r e s p e c t i v e l y . Flow r a t e s h i g h e r than 2000 1/min r a i s e the f r e s h water head order o f magnitudes above the observed i i i h e i g h t s of 0.01-0.3 m. The added f o r c e o f t h i s water c o u l d cause the i n v e s t i g a t e d l i n e r and o u t l e t s c r e e n t o f a i l . A FVR shaped as e i t h e r a frustrum, hemisphere, p a r a b o l o i d , or cuboid, adheres t o s t a b i l i t y c r i t e r i a . Turgor i s maintained f o r these f o u r shapes as l o n g as the c u r r e n t v e l o c i t y i s not g r e a t e r than 1.1, 1.6, 1.2 and 1.15 m/s, r e s p e c t i v e l y . A f t e r c r i t e r i a f o r t e c h n i c a l f e a s i b i l i t y were determined, economic f e a s i b i l i t y was i n v e s t i g a t e d . To o b t a i n a t e n year cash flow, i t was assumed t h a t the i n i t i a l s e l l i n g p r i c e o f an A t l a n t i c salmon smolt was $3.50. For one o f the t h r e e h y p o t h e t i c a l farm cases examined, net cash flow remained p o s i t i v e throughout a l l c y c l e s and a s u r p l u s was accumulated. One h y p o t h e t i c a l farm f a i l e d due t o the low number of stocked smolts. The f i n a l h y p o t h e t i c a l farm maintained a p o s i t i v e cash flow through most c y c l e s but accumulated a d e f i c i t due t o the l a r g e c a p i t a l c o s t s of PVC p i p i n g (45.32%). The lowest p r o d u c t i o n c o s t o f a smolt was $1.37. C o n c l u s i o n s from t e s t s i m u l a t i o n s on the CGSS i n d i c a t e t h a t the FVR system i s t e c h n i c a l l y and e c o n o m i c a l l y f e a s i b l e . The spreadsheet developed d u r i n g t h i s i n v e s t i g a t i o n i s concluded t o be an e f f e c t i v e t o o l t o i n v e s t i g a t e a l t e r n a t i v e s t r a t e g i e s , d e s i g n s and economies f o r smolt p r o d u c t i o n w i t h i n a FVR. i v TABLE OF CONTENTS ABSTRACT i i TABLE OF FIGURES v i LIST OF TABLES v i i i ACKNOWLEDGEMENTS i x 1.0 INTRODUCTION 1 2.0 OBJECTIVES 5 3.0 LITERATURE REVIEW 7 3.1 The Freshwater V e r t i c a l Raceway (FVR) . . . . 7 3.2 A t l a n t i c Salmon Hatchery Techniques 8 3.3 B i o l o g i c a l Requirements 11 3.3.1 Growth 11 3.3.2 Oxygen 15 3.3.3 C a r r y i n g C a p a c i t y 16 3.4 Economic C o n s i d e r a t i o n s 18 3.4.1 Model Review 18 3.4.2 Smolt P r i c e and P r o d u c t i o n Costs . . . 18 3.4.3 Market P o t e n t i a l f o r A t l a n t i c Salmon . 19 4.0 SPREADSHEET DEVELOPMENT 20 4.1 Inputs 22 4.3 Outputs 24 4.3 Temperature Regime 26 4.4 Growth and Biomass 26 4.5 Oxygen Use 27 4.6 B i o p h y s i c a l C o n s i d e r a t i o n s 29 4.6.1 D i f f e r e n c e Between S a l t / F r e s h Water Datum 29 4.6.2 Screen Head Loss 31 4.6.3 S t a b i l i t y 32 4.6.4 T u r g i d i t y 35 4.7 Economic C o n s i d e r a t i o n s 37 4.7.1 C a p i t a l Costs 37 4.7.1.1 FVR C o n s t r u c t i o n 38 4.7.1.2 B u i l d i n g and Storage Shed . . . 38 4.7.1.3 Generator 39 4.7.1.4 Water Pump 39 4.7.1.5 PVC P i p i n g 40 4.7.1.6 Boat and S k i f f 40 4.7.1.7 D i v i n g , L a b o r a t o r y and M i s c e l l a n e o u s Equipment 40 4.7.2 D i r e c t O p e r a t i n g Costs 41 4.7.2.1 Cost of Feed 41 4.7.2.2 Cost of Eggs 42 4.7.2.3 Cost of E l e c t r i c i t y 42 4.7.2.4 Cost of M e d i c a t i o n and V e t e r i n a r y 43 V 4.7.2.5 Cost of A i r F i l l s 43 4.7.3 I n d i r e c t O p e r a t i n g Costs 43 4.7.3.1 M o r t a l i t y Insurance 43 4.7.3.2 F i n a n c i n g 44 4.7.3.3 Management Cost 44 4.7.3.4 D e p r e c i a t i o n 44 4.7.3.5 Cost of Labour 44 4.7.4 Net Op e r a t i n g Revenues 45 4.7.5 Net Cash Flow 45 4.7.6 Break-Even P e r i o d 46 5.0 SPREADSHEET VALIDATION AND PARAMETER ESTIMATION . . 46 5.1 Growth Rates 47 5.2 Oxygenation and Flow Rate 48 5.3 Changes i n Head 51 6.0 SPREADSHEET ANALYSIS 51 6.1 Spreadsheet Behaviour 54 6.1.1 I n f l u e n t Flow Rate and Oxygenation . . 54 6.1.2 Changes i n Head 56 6.1.3 S t a b i l i t y and T u r g i d i t y 57 6.2 Case S t u d i e s 61 6.2.1 The Base Farm 62 6.2.2 Farm Case 2 63 6.2.3 Farm Case 3 69 7.0 CONCLUSIONS 75 8.0 FURTHER STUDY AND SUGGESTIONS 79 BIBLIOGRAPHY 81 v i TABLE OF FIGURES F i g u r e 1. Schematic Diagram of the F r e s h Water V e r t i c a l Raceway (FVR) System I l l u s t r a t i n g the P o s i t i o n o f 3 Datum P o i n t s 3 F i g u r e 2. Flow Chart I l l u s t r a t i n g T y p i c a l Timing and Mass f o r A t l a n t i c Salmon Smolt P r o d u c t i o n . . 10 F i g u r e 3. A Map of the Computation Areas as They are Located on the Computer Generated Spreadsheet S i m u l a t i o n (CGSS) 21 F i g u r e 4. A Schematic Diagram D e f i n i n g the C r i t e r i a f o r S t a b i l i t y f o r the FVR 33 F i g u r e 5. A Comparison Between Equation (5) (Iwama) and Equ a t i o n (2) ( S t a u f f e r ) as Growth Models. . . 49 F i g u r e 6. A Comparison Between Equ a t i o n (2) ( S t a u f f e r ) and Eq u a t i o n (5) (Iwama) w i t h a G c o f 0.675 i n Equ a t i o n (5) 50 F i g u r e 7. The Amount o f Oxygenation Needed Throughout a T y p i c a l P r o d u c t i o n C y c l e when the I n f l u e n t Flow Rate i s L i m i t e d t o 150, 300 and 600 1/min as P r e d i c t e d by the CGSS 52 F i g u r e 8. A Comparison Between the Height of F r e s h Water Above the S a l t Water Datum (HSD) and the C o n t r i b u t i n g P o r t i o n of which i s A t t r i b u t e d t o the Screen F r i c t i o n Loss (SFL) 53 F i g u r e 9. The R e l a t i o n s h i p o f U n l i m i t e d I n f l u e n t Flow Rate f o r I n c r e a s i n g F i s h Biomass as P r e d i c t e d by the CGSS 55 F i g u r e 10.The R e l a t i o n s h i p Between U n l i m i t e d I n f l u e n t Flow Rate and the Height Above the S a l t Water Datum (HSD) as P r e d i c t e d by the CGSS 58 F i g u r e 11. A Comparison Between the I n e r t i a l and Drag Force D i f f e r e n c e s o f 4 FVR Shapes I n d i c a t i n g the Current V e l o c i t y C r i t e r i a f o r L i n e r Turgor 60 F i g u r e 12.The E f f e c t o f Stocked Smolt Numbers on the Net Cash Flow (NCF) f o r the Base Farm over 6 C y c l e s ( M o r t a l i t y = 20%) 65 v i i F i g u r e 13.The R e l a t i o n s h i p Between Net Cash Flow and Stocked Smolt Numbers over 6 P r o d u c t i o n C y c l e s f o r the Base Farm 66 F i g u r e 14.The R e l a t i o n s h i p Between the Net Cash Flow and the M o r t a l i t y Rate over 6 P r o d u c t i o n C y c l e s f o r Farm Case 3 72 v i i i LIST OF TABLES Tabl e I. The Temperature (T) Dependent C o e f f i c i e n t s (K,M,and N,) t o Determine Oxygen Uptake Rate 16 Tabl e I I . The Center o f Buoyancy (CB), Center o f G r a v i t y (CG) and Metacenter (MC) D e f i n i n g S t a b i l i t y f o r Four D i f f e r e n t Shapes 57 Ta b l e I I I . Economic Summary of Base Farm 64 Tabl e IV. Economic Summary of Farm Case 2 67 Tabl e V. The Percentage o f the T o t a l Cost p e r Smolt f o r D i r e c t O p e rating Costs (DOPCOS) over 3 P r o d u c t i o n C y c l e s f o r Farm Case 2 68 Tabl e VI. Economic Summary of Farm Case 3 71 Tabl e VII.Summary of the Start-Up Costs and Percentage of T o t a l Cost per Smolt i n the F i r s t P r o d u c t i o n C y c l e f o r Farm Case 3 73 Tabl e V I I I . Summary of Start-Up Costs and Percentage o f T o t a l Costs f o r Smolts i n F i r s t P r o d u c t i o n C y c l e f o r Base Farm 2 74 i x ACKNOWLEDGEMENTS I am s i n c e r e l y t h a n k f u l t o a l l the people t h a t a i d e d me t e c h n i c a l l y and m o r a l l y through the course o f t h i s t h e s i s p r e p a r a t i o n . I would e s p e c i a l l y l i k e t o thank my t h e s i s s u p e r v i s o r , Dr. Royann P e t r e l l , f o r her guidance, p a t i e n c e and h u m a n i s t i c approach t o t e a c h i n g . I would a l s o l i k e t o thank Dr. V i c t o r Lo f o r b e i n g a t o l e r a n t t h e s i s committee member t h a t always had a s m i l e f o r encouragement. As w e l l , I would l i k e t o thank Dr. B e r y l March f o r her "come t o the r e s c u e " e d i t s and examination. Her e f f o r t made e v e r y t h i n g f a l l t o g e t h e r . Dr. George Iwama p r o v i d e d a l a r g e impetus f o r my p e r s i s t e n c e i n a q u a c u l t u r e r e s e a r c h and I am t h e r e f o r e g r e a t l y i ndebted. As w e l l , I would l i k e t o thank Mr. and Mrs. D. Fromberg f o r t h e i r g r a c i o u s h o s p i t a l i t y and v a l u a b l e i n f o r m a t i o n without which t h i s p r o j e c t would not have been p o s s i b l e . Some s p e c i a l thanks are i n o r d e r . The few words here won't express my g r a t i t u d e t o the f o l l o w i n g people but I imagine I'11 get around t o t h a n k i n g them i n a p r a i r i e monkey way. My s i n c e r e a p p r e c i a t i o n goes out t o Pat Turner ( f o r the i n s a n i t y ) , Ken and Suzanne Raison ( f o r b e i n g t h e r e ) , C o l i n Savage ( f o r the s a n i t y r i d e s and unmeasurable t e c h n i c a l d i r e c t i o n ) , Marck Hudon ( f o r h i s s t e a d f a s t n e s s and p r o o f r e a d i n g ) , Mike St . John ( f o r h i s o l ' s a l t e x p e r i e n c e and h e a r t ) , C i n d i Minnes ( f o r her c a r i n g ) , Dave H a z l e t t ( f o r h i s l o y a l t y ) , Deanna Simmons ( f o r her p o s i t i v i s m ) , Ray C a r r i e r ( f o r h i s comradery) and t o a l l of them f o r the a d v i s e , encouragement t h a t comes from good f r i e n d s even when a l l they've been h e a r i n g i s "I've got t o work on my t h e s i s ! " F i n a l l y , t o my Mom, Dad and s i s t e r L i n d a , thanks f o r b e i n g w i t h me i n s p i r i t and hang'in i n t h e r e w i t h me! 1 1.0 INTRODUCTION The salmon farmers of B r i t i s h Columbia are p r o d u c i n g an i n c r e a s i n g amount of A t l a n t i c salmon ( P e n n e l l , 1988). The c o s t e f f e c t i v e n e s s o f r e a r i n g P a c i f i c salmon (Oncorhynchus  spp.) i n B r i t i s h Columbia i s i n q u e s t i o n due t o slow b i o l o g i c a l growth r a t e s and market r e l a t e d problems. A l t e r n a t i v e s p e c i e s and r e a r i n g t echniques t h a t lower c o s t s are b e i n g sought (Spence, 1989). One such a l t e r n a t i v e s p e c i e s i s the A t l a n t i c salmon , Salmo s a l a r f (Blackburn, 1989). A t l a n t i c salmon a t t a i n a s a l t w a t e r - r e a d y stage (smolt) a t 30-70 grams (Hoar, 1989; F r a n t s i and J u s t a s o n , 1988). T h i s i s 5-60 grams l a r g e r than most P a c i f i c salmon smolts. In g e n e r a l , the r e a r i n g time f o r the A t l a n t i c salmon smolt i s l o n g e r than t h a t of the P a c i f i c salmon smolt ( L a i r d and Needham, 1988). In the 1989-1990 growing season the p r o d u c t i o n of A t l a n t i c salmon smolts i n B r i t i s h Columbia n e a r l y doubled (Egan and Kenny, 1990) . By 1995 the salmon p r o d u c t i o n i s p r o j e c t e d t o be 25,000 tonnes, approximately a t h i r d o f which i s expected t o be A t l a n t i c salmon. The combined e f f e c t s of these two f a c t o r s , 1) i n c r e a s e d r e a r i n g times and 2) a h i g h e r p r o p o r t i o n o f A t l a n t i c salmon s t o c k s , w i l l make p r e s e n t h a t c h e r y r e a r i n g space inadequate f o r f u t u r e i n d u s t r y needs. To address t h i s r e a r i n g space problem an i n e x p e n s i v e f reshwater l e n s system was i n v e s t i g a t e d . The f l o a t i n g v e r t i c a l raceway (FVR) can be assembled w i t h i n an o f f - s h o r e marine net-pen. I t i s f i l l e d w i t h freshwater o r v a r y i n g 2 p r o p o r t i o n s of f r e s h w a t e r / s a l t w a t e r and t h e r e f o r e f l o a t s on the denser s a l t w a t e r ( F i g . 1) . T h i s o f f s h o r e f a c i l i t y has been used t o r e a r P a c i f i c salmon from f r y t o f u l l y smolted stages i n Auke Bay, A l a s k a (Heard and M a r t i n , 1979; M a r t i n and Heard, 1987; M a r t i n and Wertheimer, 1987; M a r t i n and Wertheimer, 1989). The b e n e f i t s o f the raceways ar e : 1) low c o n s t r u c t i o n and maintenance c o s t s ; 2) reduced m o r t a l i t y ; 3) a d a p t a b i l i t y t o s i t e s t h a t are remote or without s u i t a b l e area f o r shore-based raceways; and 4) the ease o f p r o v i d i n g v a r i a b l e s a l i n i t y f o r s m o l t i f i c a t i o n and t h e r e f o r e h i g h e r smolt s u r v i v a b i l i t y (Martin and Heard, 1987). R e l i a b l e and c o n s i s t e n t u t i l i z a t i o n o f the FVR system i s expected t o p r o v i d e needed r e a r i n g space and i n c r e a s e the number o f f i s h s u r v i v i n g through the p a r r - s m o l t . The FVR system has o n l y r e c e n t l y been i n t r o d u c e d as a r e a r i n g system i n B r i t i s h Columbia. L o c a l farmers have expressed the view t h a t i n a p p r o p r i a t e and u n r e l i a b l e designs can prevent s u c c e s s f u l a p p l i c a t i o n o f the FVR systems. The d e s i g n problems are g e n e r a l l y a s s o c i a t e d w i t h s t a b i l i t y and t u r g i d i t y o f the raceway. Formulas o f f l u i d s t a t i c s can' be used t o p r e d i c t the parameters t h a t a f f o r d s t a b i l i t y and t u r g o r under g i v e n c o n d i t i o n s of head, s a l i n i t y and c u r r e n t f o r c e s (Vennard and S t r e e t , 1982). The purpose of t h i s study was t o develop a computer-generated spreadsheet s i m u l a t i o n (CGSS) t h a t w i l l be used t o t e c h n i c a l l y and e c o n o m i c a l l y e v a l u a t e d i f f e r e n t freshwater FW/SW Inlet T T T T T F i g u r e 1. Schematic Diagram of the Fresh Water V e r t i c a l Raceway (FVR) System I l l u s t r a t i n g the P o s i t i o n of 3 Datum P o i n t s . 4 v e r t i c a l raceway (FVR) systems. Every smolt farm i s c h a r a c t e r i z e d by the l o c a t i o n and can be d e s c r i b e d by a p a r t i c u l a r s e t o f s i t e s p e c i f i c parameters, i . e . s p e c i e s grown, number o f smolts, temperature regimes, water flow regimes, oxygen a v a i l a b i l i t y , FVR dimensions and d i s t a n c e s and e l e v a t i o n s t o freshwater sources. In t h i s study t h r e e FVR farm cases were i n v e s t i g a t e d . The CGSS can furthermore be a t o o l t o a s s i s t producers, i n v e s t o r s and banks i n assessment of f e a s i b i l i t y and p r o f i t a b i l i t y o f o t h e r types o f FVR systems. 5 2.0 OBJECTIVES The o b j e c t i v e s o f t h i s s t u d y were: 1) t o d e s c r i b e m a t h e m a t i c a l l y i n t e r m s o f b i o l o g i c a l and p h y s i c a l p a r a m e t e r s a f l o a t i n g v e r t i c a l r a c e w a y s y s t e m t o be u s e d t o r e a r A t l a n t i c s a l m o n s m o l t s . 2) t o a n a l y z e t h e p h y s i c a l s y s t e m f o r t h o s e c o n d i t i o n s w h i c h h e l p m a i n t a i n s t a b i l i t y and t u r g o r i n t h e FVR. 3) t o d e t e r m i n e t h e e c o n o m i c f e a s i b i l i t y o f a l t e r n a t i v e r a c e w a y s t r a t e g i e s . T he o v e r a l l h y p o t h e s i s i s t h a t a l l t y p e s o f FVR s y s t e m s a r e t e c h n i c a l l y and e c o n o m i c a l l y f e a s i b l e . Two s u b s e t s o f n u l l a n d a l t e r n a t i v e h y p o t h e s e s c a n be f o r m u l a t e d and s t a t e d a s : 1) t h e n u l l h y p o t h e s i s (H 0) i s t h a t t h e p h y s i c a l s y s t e m i s u n s t a b l e i n t e r m s o f h y d r o m e c h a n i c s . The a l t e r n a t i v e h y p o t h e s i s (H a) i s t h a t t h e s y s t e m i s s t a b l e a n d 6 2) the n u l l h y p o t h e s i s (H0) i s t h a t the FVR system i s not e c o n o m i c a l l y f e a s i b l e under a g i v e n s e t of c o n d i t i o n s . The a l t e r n a t i v e h y p o t h e s i s (Ha) i s t h a t the FVR i s f e a s i b l e under the same s e t of c o n d i t i o n s . 7 3.0 LITERATURE REVIEW 3.1 The Freshwater V e r t i c a l Raceway (FVR) A t the Northwest and A l a s k a F i s h e r i e s Centre, i n Auke Bay, A l a s k a , the freshwater l e n s system was demonstrated t o be i n e x p e n s i v e r e a r i n g space t h a t i n c r e a s e d coho salmon, Oncorhynchus k i s u t c h . s u r v i v a b i l i t y i n seawater (Martin and Heard, 1987; M a r t i n and Wertheimer, 1987; Heard and M a r t i n , 1979). The FVR systems u t i l i z e d the f o r e s h o r e space a l r e a d y a c q u i r e d f o r the marine grow-out phase o f salmon a q u a c u l t u r e . As w e l l , t h e s u r v i v a b i l i t y o f the smolts had i n c r e a s e d and can be measured by the s a l t w a t e r c h a l l e n g e ( C l a r k e , 1982; C l a r k e and Blackburn, 1978), or the number of a d u l t r e t u r n s (Martin and Wertheimer, 1987). T h i s v e r t i c a l raceway ( F i g . 1) c o n s i s t s o f t h r e e primary components: 1) a rubber r e i n f o r c e d p l a s t i c l i n e r (Hypalon); 2) a screened c i r c u l a r o u t l e t d r a i n ; and 3) a f l o a t a t i o n c o l l a r t h a t p r o v i d e s a walkway. The i n l e t p i p e d e l i v e r s freshwater t o the cone-shaped s t r u c t u r e t h a t , when f i l l e d , w i l l be o r i e n t e d v e r t i c a l l y and f l o a t upon the denser s a l t w a t e r . A 0.03-0.1 meter d i s t a n c e i s maintained between the s a l t w a t e r datum and the freshwater datum. A simple mixing d e v i c e can be a t t a c h e d t o the i n l e t p i p e t o c o n t r o l the p r o p o r t i o n of s a l t w a t e r / f r e s h w a t e r e n t e r i n g the u n i t (Heard and S a l t e r , 1978). Another FVR s i t e i s l o c a t e d approximately 80 k i l o m e t e r s northwest o f Vancouver, on the south s i d e o f Agamemnon 8 Channel, i n the S t r a i t o f Georgia. The s i t e has been produc i n g chinook (Oncorhynchus tshawytscha) and coho (Oncorhynchus k i s u t c h ) salmon smolts f o r s i x y e a r s . S t o c k i n g d e n s i t i e s g e n e r a l l y are no h i g h e r than t h e recommended 20 kg/m3 (Martin and Heard, 1987). Coho salmon o f a s i z e o f 35-50 grams are ready t o be t r a n s f e r r e d t o s a l t w a t e r (smolted) w i t h i n a 12 month p r o d u c t i o n c y c l e . Four FVR u n i t s are g r a v i t y f e d by 5, 6.4 cm diameter p o l y v i n y l c h l o r i d e (PVC) i n l e t p i p e s t h a t run approximately 400 meters from a l a k e a t an e l e v a t i o n of 120 meters above sea l e v e l . Each i n l e t p i p e has an average flow r a t e of 150 1/min. 3.2 A t l a n t i c Salmon Hatchery Techniques The s t e p s of the A t l a n t i c salmon smolt p r o d u c t i o n c y c l e are l i s t e d i n F i g u r e 2. F e r t i l i z e d eggs are moved t o t r a y s i n h a t c h i n g troughs i n October or November. The i n c u b a t i o n and y o l k - s a c stages are timed so t h a t the young w i l l b e g i n t o feed when the water warms t o 8-12°C i n A p r i l . I n c u b a t i o n temperatures as h i g h as 12°C a l l o w the eggs t o develop t o the f i r s t f e e d i n g stage i n l a t e J a n u a r y / e a r l y February, however, temperatures o f 8°-10°C are more t y p i c a l i n c u b a t i o n temperatures ( L a i r d and Needham, 1988). Subsequently, f i r s t f e e d i n g does o f t e n not s t a r t u n t i l March or l a t e r . P r o d u c t i o n times v a r y c o n s i d e r a b l y depending on the s p e c i f i c temperature regime of the f a c i l i t y ( L a i r d and Needham, 1988). A 0.1-0.2 gram f r y w i l l take from 12-18 9 months t o ac h i e v e a smolt mass o f 45 grams. Norwegian p r o d u c t i o n times p r e d i c t an 18 month c y c l e f o r A t l a n t i c salmon t o reach the seawater ready stage a t 45 grams ( B j o r n d a l , 1988; 1990). Mass (g) Time Fertilized Eggs Hatching Trays Incubation First Feeding Fry Parr Smolt (S1) Harvest 0.1-0.2 Jan/Feb 0.1-0.2 Feb/Mar 0.1-0.2 0.2 March Mar/April 1.0-12.0 May/Sept 12.0-26.0 Sept/Jan 45.0 April/May gure 2. Flow Chart I l l u s t r a t i n g T y p i c a l Timing and Mass f o r A t l a n t i c Salmon Smolt P r o d u c t i o n . 11 3 • 3 B i o l o g i c a l R e t i r e m e n t s  3.3.1 Growth The s p e c i f i c o r instantaneous growth r a t e "g" i s d e f i n e d as: g = l/w*dw/dt (1) where w = mass o f f i s h (gm) dw/dt = r a t e o f mass change a f t e r i n t e g r a t i o n , w can be determined: w = w 0e 9 t (la) where: w0 = i n i t i a l mass (gm) w = f i n a l mass (gm) t = time (days). E q u a t i o n (la) p r e d i c t s f i s h growth a c c u r a t e l y o n l y under c o n d i t i o n s where g i s cons t a n t . The parameter "g" i s dependent on i n i t i a l mass ,,w0". As the f i s h mass changes c o n t i n u o u s l y "g" a l s o changes c o n t i n u o u s l y , g e n e r a l l y d e c r e a s i n g as the f i s h ages. Eq u a t i o n ( l a ) i s o n l y v a l i d when the time i n t e r v a l " t " i s s h o r t , t y p i c a l l y one day (Ri c k e r , 1979). 12 Ac c u r a t e p r e d i c t i o n o f p r o d u c t i o n c y c l e s f o r commercial h a t c h e r i e s r e q u i r e s t h a t the most s i g n i f i c a n t f a c t o r s a f f e c t i n g growth should be r e v e a l e d and c o n t r o l l e d . B r e t t (1979) reviewed the f a c t o r s t h a t have the most s i g n i f i c a n t i n f l u e n c e on the growth o f salmonids i n h a t c h e r i e s . The f a c t o r s i n c l u d e d water temperature, r a t i o n l e v e l , d i e t , s p e c i e s , r a c e and sex u a l m a t u r i t y . The consensus i s t h a t temperature i s one o f the most important f a c t o r s a f f e c t i n g salmonid growth r a t e ( B r e t t , 1979; R i c k e r , 1979; Iwama and Tautz, 1981; B r e t t , C l a r k e , and Shelbourne, 1982). S t a u f f e r (1973) developed an equ a t i o n t o p r e d i c t f i s h growth i n h a t c h e r i e s based on data p r o v i d e d by an a n a l y s i s o f coho (Oncorhynchus k i s u t c h ) and chinook (Oncorhynchus  tshawytscha) growth. The r e s e a r c h e r concluded t h a t water temperature, f i s h mass and r a t i o n l e v e l had the most important p r e d i c t a b l e i n f l u e n c e on f i s h growth. In a hatch e r y system r a t i o n l e v e l can be assumed t o be maximum; t h e r e f o r e , the b i o l o g y o f a hatchery system can be based on the temperature-dependent growth o f f i s h (Gates, MacDonald and P o l l a r d , 1980). The e q u a t i o n t h a t S t a u f f e r developed w = (w0B + A B t ) 1 / B (2) where w = w o = f i n a l f i s h mass (gm) i n i t i a l f i s h mass (gm) 13 B = 1/3 A = a polynomial f u n c t i o n o f temperature t = time (days) i s used f o r Washington S t a t e h a t c h e r i e s (McLean, 1980) and as the b a s i s f o r a pond management program developed f o r I s l a n d S c i e n c e i n Oregon (Thomsen, 1991). Iwama and Tautz (1981) developed a simple temperature-dependent growth model f o r p r e d i c t i n g salmonid mass. The data supported the i d e a t h a t the instantaneous growth r a t e "g" was d i s c r e t e l y r e l a t e d t o temperature. They showed t h a t v a r i o u s salmonid growth models c o u l d be reduced t o the g e n e r a l form WTb = W0b + G st (3) where b = a f i t t e d exponent o f weight t = time (days) G s = growth s l o p e = T/1000 WT = weight a t time t (gm) WO = weight a t time 0 (gm) The growth s l o p e G s i s a f u n c t i o n o f r a t i o n s i z e (a constant maximum under c u l t u r e c o n d i t i o n s ) and a l i n e a r f u n c t i o n o f temperature. The exponent b i s r e l a t i v e l y i n s e n s i t i v e t o change and t h e r e f o r e allowed the model t o take the form o f 14 WT0"33 = WO0"33 + (T/1000)t (4) where T = temperature (°C) and W0-33 v s . time i s l i n e a r , and G s i s e q u i v a l e n t t o (T/1000) and i s l i n e a r w i t h temperature over most temperatures used t o r e a r salmonids (4°C-18°C). Equations (3) and (4) were developed and are used f o r P a c i f i c salmon h a t c h e r i e s . N e i t h e r o f these models s p e c i f i c a l l y address A t l a n t i c salmon growth and f i s h d i s p l a y a c o n s i d e r a b l e i n t e r s p e c i f i c range of growth r a t e s . A p a u c i t y of A t l a n t i c salmon growth models i n the Canadian a q u a c u l t u r e i n d u s t r y e x i s t (Saunders, 1991). Saunders and Harmon (1990) and Duston and Saunders (1989) have e m p i r i c a l data on j u v e n i l e A t l a n t i c salmon growth but the p e r i o d s t u d i e d does not range through the f u l l h a tchery c y c l e . Storebakken and Austreng (1987) generated r e g r e s s i o n equations t o d e f i n e instantaneous growth r a t e s f o r A t l a n t i c salmon; however, the study o n l y covered the f i r s t 6 months o f the hatchery c y c l e . To account f o r A t l a n t i c salmon (and o t h e r s p e c i e s ) growth r a t e s , Iwama and F i d l e r (1989) added a v a r i a b l e growth c o e f f i c i e n t (Gc) t o equation 2. The equa t i o n took the form WT0"33 = WO0-33 + G c (T/1000) t (5) 15 The s i m p l i c i t y and f l e x i b i l i t y o f t h i s model makes i t a p p r o p r i a t e f o r r o u t i n e hatchery purposes. 3.3.2 Oxygen S i n c e the oxygen content o f water i s v e r y low compared t o t h a t o f a i r , growth and s u r v i v a l o f f i s h can be l i m i t e d by the i n f l u e n t oxygen c o n c e n t r a t i o n (Meade, 1975). For salmonids the minimum r e q u i r e d water oxygen c o n c e n t r a t i o n s h o u l d not f a l l below 6 mg/1 ( L a i r d and Needham, 1988). The farmer has two o p t i o n s t o ensure t h a t the f i s h a re p r o v i d e d w i t h adequate oxygen: 1) have a v a i l a b l e s u f f i c i e n t flow r a t e and/or 2) add supplemental oxygen, i . e . oxygenation ( L a i r d and Needham, 1988) . L i a o (1971) developed an equ a t i o n t o p r e d i c t oxygen requirements f o r salmonids. L i a o r e l a t e d oxygen consumption "RO" t o f i s h mass and water temperature such t h a t : RO = K(1.8ITEMP + 32) NIWEI M (6) where: RO = oxygen consumption (mg/kghr) IWEI = i n i t i a l mass (gm) ITEMP = i n i t i a l temperature (°C) and the c o n s t a n t s K,N and M are g i v e n i n T a b l e 1. 16 Tab l e I . The Temperature (T) Dependent C o e f f i c i e n t s (K,M,and N,) t o Determine Oxygen Uptake Rate K M N T <= 10 °C 9.828E-04 -0.194 3.20 T > 10°C 6.689E-04 -0.194 2.12 T h i s formula has been u t i l i z e d e x t e n s i v e l y t o determine oxygen requirements f o r coho and chinook salmon. Cook and Canton (1988) developed a spreadsheet program t h a t can be used i n c o n j u n c t i o n w i t h equation (6) t o c a l c u l a t e p e r c e n t oxygen s a t u r a t i o n o f the water. 3.3.3 C a r r y i n g C a p a c i t y The c a r r y i n g c a p a c i t y i s a f u n c t i o n o f f i s h biomass and the water's c a p a c i t y t o c a r r y oxygen. The f a c i l i t i e s oxygen c a p a c i t y w i l l l i m i t the number of smolts produced. Most farms w i l l have a freshwater l i m i t , a r e l a t e d oxygen l i m i t and t h e r e f o r e a smolt ( f i s h biomass) p r o d u c t i o n l i m i t . Weber (1970) demonstrated t h a t knowing the oxygen consumption r a t e (Eq. 3) and the oxygen s a t u r a t i o n a l l o w s the p r e d i c t i o n o f the average d a i l y pond e f f l u e n t oxygen c o n c e n t r a t i o n . Weber a l s o determined e f f l u e n t oxygen c o n c e n t r a t i o n as a f u n c t i o n of c a r r y i n g c a p a c i t y . McLean 17 (1980) rear r a n g e d Weber's equ a t i o n t o s o l v e f o r c a r r y i n g c a p a c i t y a t a g i v e n e f f l u e n t oxygen c o n c e n t r a t i o n . McLean's e q u a t i o n i s as f o l l o w s : L = 28500*02SAT - 60X_*(T + 32.035) (7) R 0*(T + 32.035) where: L = c a r r y i n g c a p a c i t y (kg/l/min) 02SAT = p e r c e n t oxygen s a t u r a t i o n X 0 = e f f l u e n t oxygen c o n c e n t r a t i o n (mg/1) T = temperature (°C) R 0 = oxygen consumption r a t e (mg/kghr) 18 3.4 Economic C o n s i d e r a t i o n s 3.4.1 Model Review Egan, Egan and Wright (1989) ; Lee (1988) ; Combs (1986) and MacGregor (1986) have developed spreadsheet models f o r f i n a n c i a l a n a l y s i s o f the p o s t - h a t c h e r y phase o f salmon farming i n B r i t i s h Columbia. Other spreadsheet models have been produced by p r i v a t e c o n s u l t i n g companies such as Scantech Resources L i m i t e d , Entech Environmental C o n s u l t a n t s and E n v i r o c o n L i m i t e d (Lee, 1988). The above models s i m u l a t e the economics o f a p o s t -h a t c h e r y f i s h farm system. The o b j e c t i v e o f these models was t o determine economic f e a s i b i l i t y and p r o v i d e a f i n a n c i a l a n a l y s i s of a standard p o s t - h a t c h e r y f i s h farm. T y p i c a l investment measures used by these models were cash flow, i n t e r n a l r a t e of r e t u r n , net p r e s e n t v a l u e , breakdown of i n p u t c o s t s and break-even p r i c e . The main emphasis was on economic i n d i c a t o r s and investment e v a l u a t i o n . None o f the reviewed models c o n s i d e r e d e i t h e r the economic or t e c h n i c a l f e a s i b i l i t y o f a h a t c h e r y system. 3.4.2 Smolt P r i c e and P r o d u c t i o n Costs The s e l l i n g p r i c e o f a 50-60 gram A t l a n t i c salmon smolt i n B.C. was $3.50 as o f February, 1991 ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991). T h i s p r i c e v a r i e d w i t h i n t h a t month from $3.25-$3.75 per smolt. The p r o d u c t i o n c o s t s f o r an A t l a n t i c salmon smolt i n B.C. have ranged from $2.00-19 $3.00 (Kenny, 1991). B j o r n d a l (1990) l i s t e d the p r o d u c t i o n c o s t o f an A t l a n t i c salmon smolt i n Norway t o v a r y between $1.22-$1.88. B j o r n d a l (1990) a l s o noted the S c o t t i s h A t l a n t i c salmon p r o d u c t i o n c o s t was $1.60 per smolt. The B.C. smolt p r o d u c t i o n c o s t s are c o n s i d e r a b l y h i g h e r than i n Europe. As p r o d u c t i o n c o s t breakdowns were not a v a i l a b l e f o r the hatchery stage o f the p r o d u c t i o n c y c l e , i t i s d i f f i c u l t t o determine the cause of the c o s t d i f f e r e n t i a l . 3.4.3 Market P o t e n t i a l f o r A t l a n t i c Salmon In 1978 the Canadian government sponsored a f e a s i b i l i t y study on the commercial c u l t u r e of A t l a n t i c salmon a t Deer I s l a n d , New Brunswick ( S u t t e r l i n e t . a l . , 1981). S i n c e then the p r i v a t e s e c t o r has c o n t i n u e d t o develop the i n d u s t r y i n e a s t e r n Canada. By 1987 A t l a n t i c salmon were b e i n g commercially farmed i n B r i t i s h Columbia. In 1990 15% of the farmed salmon i n B.C. were A t l a n t i c salmon (Egan and Kenny, 1990). By 1995 the salmon a q u a c u l t u r e p r o d u c t i o n i n B r i t i s h Columbia i s p r o j e c t e d t o be 25,000 m e t r i c tonnes (MT). An i n c r e a s i n g p r o p o r t i o n of t h i s p r o d u c t i o n w i l l be A t l a n t i c salmon. By the year 2000 i t has been p r o j e c t e d t h a t A t l a n t i c salmon and chinook w i l l be r a i s e d i n equal numbers i n B r i t i s h Columbia (Needham, 1990). Between 1955 and 1981 the p r i c e o f A t l a n t i c salmon, d e f l a t e d by the consumer p r i c e index, has i n c r e a s e d by about 54% ( K a b i r and R i d l e r , 1984). The i n c r e a s e d demand f o r A t l a n t i c salmon i n B.C. i s r e f l e c t e d i n the s e l l i n g p r i c e o f the A t l a n t i c smolt. As of February, 1991 the c o s t of an A t l a n t i c salmon smolt was $3.50 ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991) . These i n c r e a s i n g f i g u r e s support a s t r o n g domestic market demand f o r farmed A t l a n t i c salmon. Both demand and p r i c e f o r A t l a n t i c salmon w i t h i n Canada suggest t h a t the domestic market should grow by 4.2% a n n u a l l y ( R i d l e r and K a b i r , 1988). 4.0 SPREADSHEET DEVELOPMENT Mathematical analogs of a q u a c u l t u r e systems have t h r e e uses: p l a n n i n g and r e s e a r c h ; i d e n t i f i c a t i o n and c o n t r o l ; and f i n a l l y economic a n a l y s i s ( F r i d l e y , 1986). Three g e n e r a l c a t e g o r i e s o f m o d e l l i n g are a v a i l a b l e t o the i n v e s t i g a t o r t o i n t e g r a t e r e l a t i o n s h i p s : s i m u l a t i o n and v a l i d a t i o n , mathematical programming and spreadsheet a n a l y s i s . The microcomputer spreadsheet i s an easy medium f o r communication between r e s e a r c h e r s , t e c h n i c i a n s , b u s i n e s s and banking p e r s o n n e l and the producer (Leung and Rowland, 1989) and was t h e r e f o r e chosen t o si m u l a t e and analyze a FVR. A map of the Quattro Pro spreadsheet t h a t was developed over the course of t h i s study i s d e p i c t e d i n F i g u r e 3. A person f a m i l i a r w i t h spreadsheets w i l l be a b l e t o f u l l y manipulate v a r i a b l e s and parameters t o query a t y p i c a l farm case. 21 != "° I -P. 3 r— TJ C CO CO o O 3 73 C CO (A 1 | 2 .2 O CQ (A O £ o fl) c (A o Ec <A so. COI (A u c Co CI c fl) m 1 in I o rati i o ii nu k. ro pit rati i o ii fl> LL pit fl) > ro a fl> fl) O O z T3 C ro •H ^ (D "(75 «J fl) k. 5 Q O £ 0 * " CO .2 fl) «»- £ k. 'TJ CD LL 0) "55 T3 a > c (/) > ro F i g u r e 3 . A Map of the Computation Areas as They are Located on the Computer Generated Spreadsheet S i m u l a t i o n (CGSS). G e n e r a l l y , a computer-generated spreadsheet (CGSS) i s i n i t i a t e d from a s e t o f v a r i a b l e i n p u t s . A s e r i e s o f computations, r e s t r i c t e d by system assumptions and parameters, are then made. The assumptions and parameters have been r e s o l v e d from the l i t e r a t u r e , a c t u a l FVR s i t e measurements and model e s t i m a t i o n . The r e s u l t s o f the computations are d i s p l a y e d as outputs i n the areas r e p r e s e n t e d i n F i g u r e 3. The CGSS was developed on the f o l l o w i n g assumptions: 1) a 12-18 month p r o d u c t i o n c y c l e 2) a f i n a l s t o c k i n g d e n s i t y o f 20 kg/m3 3) satiation/maximum r a t i o n f e e d i n g 4) e l e c t r i c i t y i s ob t a i n e d from B.C. Hydro g r i d 5) b o t t l e d oxygen through a d i f f u s i o n stone i s used f o r oxygenation 4.1 Inputs The CGSS can be used t o determine and as s e s s the b i o l o g i c a l , t e c h n i c a l and economical f e a s i b i l i t y o f an FVR p r o d u c t i o n system g i v e n a s e t o f v a r i a b l e i n p u t s . These i n p u t s i n c l u d e : 1) temperature regime - i n terms of the average monthly temperature (°C); 2) growth c o e f f i c i e n t (Gc) -0.675 as determined f o r A t l a n t i c salmon (see s e c t i o n 5.1); 3) i n i t i a l smolt number -which can range from 1-120,000 smolts; 4) i n i t i a l smolt mass -which i s a c t u a l l y t he a l e v i n o r f r y mass when i t i s f i r s t i n t r o d u c e d i n t o t he FVR u n i t u s u a l l y between 0.05-0.2 grams); 5) decimal f r a c t i o n mortality rate -which i s the expected m o r t a l i t y r a t e o f the f i s h over t h e e n t i r e smolt p r o d u c t i o n c y c l e i . e . 0.20; 6) dimensions of FVR -g i v e n i n meters as the diameter, the depth from the o u t l e t s c r e e n t o the s a l t w a t e r datum, and, i n the case o f a hemisphere, the r a d i u s , o f the u n i t ; 7) current v e l o c i t y -which i s the expected v e l o c i t y o f the seawater a t the s i t e i . e . 0.5 m/s; 8) i n f l u e n t oxygen concentration -which i s the amount of oxygen i n the source water (mg/1); 9) s a l t and freshwater s a l i n i t y -which are v a l u e s g i v e n i n p a r t s p e r thousand (%.) of the s a l i n i t y i n s i d e and o u t s i d e o f the FVR; 10) flow rate -which i s the volume p e r u n i t time o f the i n l e t water supply (1/min); 11) gravity flow or pump (G/P) -which g i v e s the u s e r the c h o i c e o f e v a l u a t i n g c o s t s w i t h (P), o r without (G) an e l e c t r i c pump (see below); 12) oxygenation (Y/N) -which a g a i n p r o v i d e s the u s e r w i t h the c h o i c e o f e v a l u a t i n g the c o s t s w i t h (Y), o r without (N) supplemental oxygen. 13) elevation above water source -which determines the p o r t i o n of the pumping c o s t s t h a t accounts f o r l i f t i n g water from a source h e i g h t (m); 14) distance from water source -which determines t h e p o r t i o n o f the pumping c o s t s t h a t accounts f o r moving water through a PVC p i p e from the water source (m). The i n p u t s p r o v i d e d above w i l l be used w i t h i n the equations d e s c r i b e d w i t h i n t h i s s e c t i o n . The computations are performed and subsequent output v a l u e s are determined. 4.3 Outputs With the i n p u t s and computations the CGSS c a l c u l a t e s the f o l l o w i n g outputs: 1) monthly biomass estimates -where i n d i v i d u a l smolt mass i s expressed i n grams (g) and t o t a l crop biomass i s expressed i n kilograms (kg); 2) r e s p i r a t i o n and oxygenation -where f i s h r e s p i r a t i o n i s expressed i n m i l l i g r a m s of oxygen per k i l o g r a m of f i s h every hour (mg/kghr) and supplemental oxygen i s expressed s i m i l a r l y ; 3) carrying capacity - i . e . the p o t e n t i a l mass o f f i s h t h a t can be s u s t a i n e d by the oxygen content i n the c u l t u r e water expressed i n kilograms o f f i s h f o r every l i t r e o f water per minute (kg/1/min); 4) volume and s p e c i f i c weight - t h a t i s t h e v o l u m e i n c u b i c m e t e r s (m3) o f w a t e r o f t h e FVR and t h e s p e c i f i c w e i g h t o f s a l t and f r e s h w a t e r i n Newtons f o r e v e r y c u b i c m e t e r (N/m3) ; 5) the number of PVR units - a s t h e b i o m a s s i n c r e a s e s w i t h i n e a c h u n i t t h e s t o c k i n g d e n s i t y i n c r e a s e s . When t h e s t o c k i n g d e n s i t y r e a c h e s 20 kg/m 3 t h e CGSS assumes a n o t h e r u n i t w i l l be a d d e d t o t h e f a c i l i t y i n o r d e r t o accommodate t h i s i n c r e a s i n g b i o m a s s . The p r i c e o f a l l t h e u n i t s a r e assumed t o be a c c o u n t e d f o r i n t h e c a p i t a l c o s t s ; 6) s t a b i l i t y and t u r g i d i t y - o f f o u r d i f f e r e n t s h a p e s ( f r u s t r u m , c u b o i d , h e m i s p h e r e and p a r a b o l o i d ) o f FVR-where s t a b i l i t y i s b a s e d on c r i t e r i a e x p l a i n e d b e l o w and t u r g i d i t y d e p e n d e n t on t h e f o r c e , i n Newtons, a p p l i e d on t h e i n n e r and o u t e r s u r f a c e s o f t h e l i n e r ; 7) c a p i t a l and operating costs - t h a t l a r g e l y d e p e n d on e c o n o m i c a s s u m p t i o n s s t a t e d b e l o w ; 8) t o t a l revenues and net farm income - t h a t a r e d e t e r m i n e d m o s t l y by h a r v e s t v a l u e ; 9) break-even period - t h a t r e f l e c t s when t h e f a r m r e v e n u e s c a n o f f s e t t h e t o t a l i n v e s t m e n t . The f o l l o w i n g s e c t i o n s a r e i n c l u d e d t o i l l u s t r a t e how t h e CGSS was d e v e l o p e d . 26 4 . 3 T e m p e r a t u r e R e g i m e A s d e s c r i b e d a b o v e , t e m p e r a t u r e i s t h e m a i n e n v i r o n m e n t a l f a c t o r a f f e c t i n g g r o w t h ( s e e s e c t i o n 3 . 3 . 1 ) . I t i s i m p o r t a n t t o u s e a t e m p e r a t u r e r e g i m e t h a t a c c u r a t e l y r e f l e c t s t h e s i t u a t i o n o f t h e h a t c h e r y s y s t e m . T h e s p r e a d s h e e t i n t h i s i n v e s t i g a t i o n u t i l i z e d a v e r a g e m o n t h l y t e m p e r a t u r e s t h a t w e r e o b t a i n e d f r o m t h e Agamemnon FVR s i t e . A n y r e g i m e may , h o w e v e r , b e s u b s t i t u t e d t o s u i t t h e p a r t i c u l a r s i t e i n q u e s t i o n . 4 . 4 G r o w t h a n d B i o m a s s E q u a t i o n (5) was u s e d w i t h i n i t i a l s m o l t mass a n d t h e g r o w t h c o e f f i c i e n t t o d e t e r m i n e t h e f i n a l s m o l t m a s s . M a s s was d e t e r m i n e d f o r 30 d a y ( m o n t h l y ) i n c r e m e n t s . T h i s mass was t h e n u s e d a s t h e i n i t i a l mass f o r t h e n e x t m o n t h l y c a l c u l a t i o n . A m o r t a l i t y c a l c u l a t i o n i s i n c l u d e d t o o b t a i n t o t a l n u m b e r s o f f i s h f o r e a c h m o n t h l y i n c r e m e n t . V a l u e s o f f i s h mass a n d t o t a l f i s h n u m b e r s w e r e m u l t i p l i e d t o o b t a i n t o t a l f i s h b i o m a s s . F e e d a m o u n t s w e r e t h e n c a l c u l a t e d . T h e f e e d a m o u n t s d e p e n d o n M o o r e - C l a r k e f e e d i n g c h a r t s ( M o o r e - C l a r k e , 1 9 9 1 ) . T h e p e r c e n t a g e o f b o d y mass f e d t o t h e f i s h p e r d a y i s d e p e n d e n t o n s i z e o f f i s h a n d t e m p e r a t u r e . I t w i l l v a r y f r o m 0 . 9 - 7 . 0 % / d a y . 4.5 Oxygen Use E q uations (6) and (7) are used i n s u c c e s s i o n t o determine the oxygen consumption (mg/kghr) and c a r r y i n g c a p a c i t y ( k g / l / m i n ) . T o t a l oxygen consumed (mg/hr) i s a l s o computed. The flow r a t e , Q (1/min), can then be determined as i t corresponds t o the c a r r y i n g c a p a c i t y . The flow r a t e i s o b t a i n e d by d i v i d i n g the t o t a l biomass of f i s h by the c a r r y i n g c a p a c i t y as Q = WEI/L (8) where Q = flow (1/min) WEI = t o t a l biomass of f i s h (kg) L = c a r r y i n g c a p a c i t y (kg/l/min) To m i t i g a t e the e f f e c t s o f inadequate water flow, as mentioned i n s e c t i o n 3.3.3, i t i s p o s s i b l e t o supplement the e x i s t i n g oxygen wi t h compressed oxygen (Kepenyes, 1984). Compressed oxygen i s i n e x p e n s i v e and convenient f o r remote s i t e s . The supplement r a t e i s a f u n c t i o n o f flow, i n f l u e n t and e f f l u e n t oxygen c o n c e n t r a t i o n s , volume and s t o c k i n g d e n s i t y such t h a t : RA = (SD*V*R 0)-Q(X S-X Q)/SD*V where (9) 28 RA = oxygenation r a t e (mg/kghr) SD = s t o c k i n g d e n s i t y (kg/m3) V = volume of v e r t i c a l raceway (m3) X s = i n f l u e n t oxygen c o n c e n t r a t i o n (mg/1). Q = flow r a t e (m3/hr) The r a t e a t which the oxygen i s t r a n f e r r e d i n t o a s o l u b l e form i s a l s o c o n s i d e r e d . I t i s assumed t h a t a d i f f u s i n g stone i n t r o d u c e s compressed oxygen i n t o the FVR a t a r a t e RA m u l t i p l i e d by the oxygen a b s o r p t i o n e f f i c i e n c y . The a b s o r p t i o n e f f i c i e n c y i s d e f i n e d by the amount o f oxygen absorbed by the water d i v i d e d by the oxygen added t o the water and i s used t o account f o r the mechanisms i n v o l v e d i n oxygen t r a n s f e r . Oxygen i s t r a n s f e r r e d from the bubbles of a stone d i f f u s e r t o the water by d i f f u s i o n a c r o s s the l i q u i d f i l m . The t w o - f i l m t h e o r y of gas t r a n s f e r a p p l i e s t o t h i s s i t u a t i o n (Tchobanoglous, 1979). Oxygen d i f f u s e s i n t o the water as the bubble r i s e s , the oxygen c o n c e n t r a t i o n i n the bubble and the c o n c e n t r a t i o n g r a d i e n t between water and gas decreases as the bubble r i s e s . Submergence depth o f the d i f f u s e r stone i n c r e a s e s oxygen a b s o r p t i o n w i t h i n c r e a s i n g depth. I t i s assumed t h a t the oxygen a b s o r p t i o n e f f i c i e n c y o f the d i f f u s i n g stone i s 30% (Tchobanoglous, 1979). 4.6 B i o p h y s i c a l C o n s i d e r a t i o n s 4.6.1 D i f f e r e n c e Between S a l t / F r e s h Water Datum The fundamental approach t o p r e d i c t head changes i n a body o f l i q u i d (the FVR) i s t o u t i l i z e t he mass balance flow r a t e e q u a t i o n and two usages of B e r n o u l l i ' s e q u a t i o n . From the p r i n c i p l e o f mass balance and assuming the l i q u i d i s of con s t a n t d e n s i t y , pQ = pA,V, = pA 2V 2 (10) where p = d e n s i t y o f water (kg/m3) Q = i n p u t flow r a t e (1/sec) A, = c r o s s - s e c t i o n a l area a t top of raceway (m2) V, = v e l o c i t y a t the s u r f a c e o f the raceway (m/s) A 2 = c r o s s - s e c t i o n a l area a t bottom of raceway (m2) V 2 = v e l o c i t y a t the bottom o f the raceway (m/s) The v e l o c i t y a t the bottom of the tank i s c a l c u l a t e d u s i n g e q u a t i o n 6 and Q, the i n p u t flow r a t e . Two usages of B e r n o u l l i ' s e quation w i l l be used t o c a l c u l a t e the head (m) above the freshwater datum. The procedure f o l l o w s . The g e n e r a l form o f B e r n o u l l i ' s e quation f o r 2 p o i n t s w i t h i n a c o n t r o l volume i s : P / Y , + V / 2 g + z, = P 2 / Y 2 + V 2 2 / 2 g + z2 + AH (11) 30 where P1 = Press u r e a t p o i n t 1 (Pa) P 2 = Press u r e a t p o i n t 2 (Pa) Y l = S p e c i f i c weight o f l i q u i d a t p o i n t 1 (N/m3) y 2 = S p e c i f i c weight o f l i q u i d a t p o i n t 2 (N/m3) g = a c c e l e r a t i o n due t o g r a v i t y (m/s 2) z 1 = depth a t p o i n t 1 (m) z 2 = depth a t p o i n t 2 (m) A H = f r i c t i o n a l head l o s s (m) One usage of B e r n o u l l i ' s e quation i s used t o f i n d the pr e s s u r e a t the o u t l e t s c r e e n depth, P 2. In t h i s case, the freshwater datum i s , z.,=0, V 2 i s determined from E q u a t i o n (6) , Yi = Y2 = Yf (freshwater) and P, = 0. The depth, z 2 equals the known d e s i g n l e n g t h o f the FVR, TL. The p r e s s u r e P 2 i s s o l v e d f o r as f o l l o w s : P 2 = (YfMV-V.,2 )/2g - A H y f - T L Y f ) (12) where A H = the combined f r i c t i o n l o s s e s due t o p r e s s u r e l o s s a c r o s s the scree n and l i n e r w a l l f r i c t i o n . The second usage o f B e r n o u l l i ' s equations uses P 2 from e q u a t i o n (12) t o s o l v e f o r h, the d i s t a n c e between the s a l t and f r e s h water datum. In t h i s case the s a l t w a t e r datum i s z 1 = 0, z 2= H , where H = TL-h, Y l = Y2 = Y s ( s a l t w a t e r ) and P1 = 0. P 2 = H Y S = " (TL - h)y 31 (13) The parameter P 2 i s s u b s t i t u t e d i n t o e q u a t i o n (13) , and the e q u a t i o n i s rearranged t o s o l v e f o r h, h = L Z f i Y ^ z 2 )/2q) ~ A H Y F - T L ( Y & - Y f l (14) Y s The s p e c i f i c weights o f waters of d i f f e r e n t s a l i n i t i e s are estimated w i t h the I n t e r n a t i o n a l Equation o f S t a t e of Sea Water (Pond and P i c k a r d , 1989) 4,6.2 Screen Head Loss The s c r e e n a t the bottom of the v e r t i c a l raceway causes f r i c t i o n l o s s t h a t w i l l d i m i n i s h the e f f e c t i v e area o f the o u t l e t . T h i s r e f l e c t s as a f r i c t i o n a l head l o s s , A H , p r e d i c t e d by the f o l l o w i n g e q u a t i o n (Beveridge, 1987): A H = C*(V 2/2g) (15) where C = d i s c h a r g e c o e f f i c i e n t V = v e l o c i t y a t s c r e e n The d i s c h a r g e c o e f f i c i e n t , C, i s a f u n c t i o n of v e l o c i t y and s c r e e n mesh s i z e . T h i s c o e f f i c i e n t i s e m p i r i c a l l y c a l c u l a t e d (Beveridge, 1987) and i s t h e r e f o r e s p e c i f i c t o a g i v e n s i t u a t i o n . The *H measurements from the Agamemnon s i t e and from Heard and M a r t i n (1978) were used t o es t i m a t e C (see s e c t i o n 5.3). 4.6.3 S t a b i l i t y For a body such as the f l o a t i n g v e r t i c a l raceway, s t a b i l i t y i s important. S t a b i l i t y means t h a t a body w i l l r e t u r n t o the o r i g i n a l p o s i t i o n a f t e r b e i n g r o t a t e d about a v e r t i c a l o r h o r i z o n t a l a x i s by wave or c u r r e n t f o r c e s . A f l o a t i n g body i s i n e q u i l i b r i u m w i t h the c e n t e r of g r a v i t y (CG) above the c e n t e r o f buoyancy (CB) on a v e r t i c a l a x i s . I f a f o r c e causes the body t o r o t a t e s l i g h t l y , although the l o c a t i o n o f the c e n t e r o f g r a v i t y remains f i x e d , the l o c a t i o n o f the c e n t e r o f buoyancy s h i f t s because the d i s p l a c e d volume o f f l u i d has changed ( F i g . 4 ) . The buoyant f o r c e and the weight o f the body c r e a t e a couple t h a t tends t o produce a r i g h t i n g moment t h a t r e t u r n s the body t o the o r i g i n a l p o s i t i o n . T h i s d e f i n i t i o n o f s t a b i l i t y can a l s o be made wit h r e f e r e n c e t o the p o i n t o f i n t e r s e c t i o n o f the v e r t i c a l a x i s and the l i n e o f a c t i o n o f the buoyant f o r c e . T h i s p o i n t of i n t e r s e c t i o n i s known as the metacenter (MC). A f l o a t i n g body i s s t a b l e i f CG i s below MC and u n s t a b l e i f CG i s above MC. The f i r s t s t e p t o determine i f a freshwater i n v e r t e d cone, o r another shape, would be s t a b l e w h i l e f l o a t i n g i n F i g u r e 4. A Schematic Diagram D e f i n i n g the C r i t e r i a f o r S t a b i l i t y f o r the FVR. 34 s a l t w a t e r i s t o determine the submerged depth o f the cone, H = TL - h (see s e c t i o n 4.6.1). CG i s the c e n t r o i d o f the cone and can be determined as CG = (H + h)/4 S i m i l a r l y CB can be determined as the c e n t r o i d o f the cone t h a t i s submerged t o depth D i n s a l t w a t e r as CB = H/4 The d e t e r m i n a t i o n as t o whether the c e n t e r o f g r a v i t y i s below o r above the metacenter can be made q u a n t i t a t i v e l y by u s i n g the f o l l o w i n g e quation t o determine the d i s t a n c e from CB t o MC: MB = I/V d (18) where MB = d i s t a n c e from CB t o MC I = moment of i n e r t i a » . V d = volume of f l u i d d i s p l a c e d For an i n v e r t e d cone the moment of i n e r t i a i s g i v e n by I = DIAP*H3/36 (19) 35 and the volume o f f l u i d d i s p l a c e d by Vd = (1/3) (*r*DIAP2 *D/4) (20) where DIAP i s an i n p u t o f the top diameter o f the cone. I t e r a t i o n s used d u r i n g the d e t e r m i n a t i o n o f s t a b i l i t y are performed on a hemisphere, cu b o i d and p a r a b o l o i d t o determine the r e l a t i v e s t a b i l i t y o f each. 4.6.4 T u r g i d i t y Drag f o r c e s due t o c u r r e n t s o f s u f f i c i e n t magnitude can a f f e c t the t u r g i d i t y o f the v e r t i c a l raceway. The FVR i s t u r g i d i f the sum of the f o r c e s a c t i n g on the o u t s i d e o f the l i n e r (F s) , the p r e s s u r e drag, i s equal t o the sum o f the f o r c e s a c t i n g on the i n s i d e o f the l i n e r (F f) . I f F f<F s, or F f>F s, then the l i n e r i s not t u r g i d . When a c u r r e n t o f magnitude F i s a p p l i e d t o the FVR then F s i n c r e a s e s . The f o r c e , F, a p p l i e d t o the v e r t i c a l raceway can be determined by: F f DaV*A/2g (21) where .074R-.2 a d e n s i t y (kg/m3) V v e l o c i t y (m/sec) A p r o j e c t e d area normal t o d i r e c t i o n o f flow The Reynold's number, R, f o r a body o f r e v o l u t i o n , t h a t i s a p a r a b o l o i d , hemisphere, cuboid or frustrum, can be o b t a i n e d from the r e l a t i o n s h i p R = DV/v (22) where D = diameter of body v = ki n e m a t i c v i s c o s i t y The p r e s s u r e or form drag F s i s d i r e c t l y p r o p o r t i o n a l t o the p r o j e c t e d area of the body normal t o the d i r e c t i o n of water flow (Eq. 21). Three FVR shapes, o r forms, were chosen b e s i d e s the f r u s t r u m t o r e p r e s e n t a c r o s s s e c t i o n o f form drags (the c u b o i d b e i n g the shape w i t h the g r e a t e s t form drag and the hemisphere b e i n g the shape w i t h the l e a s t form d r a g ) . Each of these d i f f e r e n t forms would be expected t o m a i n t a i n t u r g i d i t y under d i f f e r e n t c u r r e n t v e l o c i t i e s . The c u r r e n t f o r c e o u t s i d e of the l i n e r F s must now be measured a g a i n s t the i n e r t i a l , s t a t i c f o r c e i n s i d e of the v e r t i c a l raceway F f t o determine i f t u r g o r i s maintained. The f o r c e F f i s e q u i v a l e n t t o the f o r c e a p p l i e d by the freshwater head determined by adding V d, from e q u a t i o n (20) , and AH, from e q u a t i o n (10), and then m u l t i p l y i n g t h i s sum by the s p e c i f i c weight o f freshwater (Pond and P i c k a r d , 1989). 37 4.7 Economic C o n s i d e r a t i o n s To determine i f a FVR system i s e c o n o m i c a l l y f e a s i b l e a breakdown o f i n p u t c o s t s i s f i r s t e s t a b l i s h e d . Subsequently, the net cash flow (NCF) and t h e r e f o r e the break-even p e r i o d can be determined. The f o l l o w i n g c a l c u l a t i o n s a re needed t o determine the NCF: 1) the t o t a l s t a r t up c o s t s f o r the FVR system, the c a p i t a l c o s t s ; 2) the c o s t s o f o p e r a t i n g the farm, t h a t i s the d i r e c t and i n d i r e c t o p e r a t i n g c o s t s and; 3) the revenue o b t a i n e d by s e l l i n g the smolts, the t o t a l revenue. The break-even p e r i o d i s r e s o l v e d when the NCF i s p o s i t i v e and when a s u r p l u s i s accumulating. F a c t o r s c o n t r i b u t i n g t o the NCF and break-even p e r i o d w i l l be e x p l a i n e d i n t h i s s e c t i o n . An i n f l a t i o n r a t e o f 4% per yea r i s taken i n t o c o n s i d e r a t i o n . As w e l l a t ax r a t e i s s e t a t 33% o f the net o p e r a t i n g revenue. I t i s assumed t h a t i f the net o p e r a t i n g revenue i s n e g a t i v e t h a t no tax or tax c r e d i t w i l l be imposed. 4.7.1 C a p i t a l Costs The c a p i t a l c o s t s a re the i n i t i a l c o s t s t o s t a r t up a FVR o p e r a t i o n . These c o s t s do not i n c l u d e the c o s t s a s s o c i a t e d w i t h the r o u t i n e o p e r a t i o n o f smolt growout. C a p i t a l c o s t s i n c l u d e c o s t s o f : l i n e r , f l o a t s and mooring, b u i l d i n g and sto r a g e shed, generator, motor and pump, a s k i f f , PVC p i p i n g , boat, d i v i n g equipment, l a b equipment and m i s c e l l a n e o u s t o o l s . 38 4.7.1.1 FVR C o n s t r u c t i o n The c o s t o f the FVR c o n s t r u c t i o n i s a f u n c t i o n of 3 f a c t o r s : l i n e r c o s t ; f l o a t i n g c o l l a r c o s t and mooring. The f l o a t i n g c o l l a r i s c o n s i d e r e d t o be a t y p i c a l aluminum framed s t r u c t u r e common i n the i n d u s t r y . A t y p i c a l c o s t f o r each f l o a t and walkway system i s $5000 (Fromberg, 1991). The mooring charges are assumed t o be $5000 t o s t a r t up the farm and then $1500 f o r each i n d i v i d u a l FVR u n i t (Egan, Egan and Wright, 1989). The c o s t o f l i n e r c o n s t r u c t i o n i s dependent on s u r f a c e area. The dimensions are o b t a i n e d as i n p u t s (see s e c t i o n 4.1). The m a t e r i a l s used f o r c o n s t r u c t i o n are t y p i c a l l y a 1.14 mm t h i c k Hypalon or S h e l t e r i t e l i n e r . The c o s t o f the m a t e r i a l i s q u i t e v a r i a b l e . S u p p l i e r s i n the U.S. p r o v i d e the b e s t p r i c e of $8.81/m2 w h i l e Canadian s u p p l i e r s may be as h i g h as $45.21/m2. The h i g h e r c o s t has been used i n the spreadsheet. The l i n e r and mooring have no salvage v a l u e . The l i f e expectancy o f the l i n e r , f l o a t s and mooring are 3, 10 and 10 y e a r s , r e s p e c t i v e l y . 4.7.1.2 B u i l d i n g and Storage Shed The b u i l d i n g and s t o r a g e shed are n e c e s s a r y t o accommodate employees, equipment and feed. The b u i l d i n g p r i c e has been s e t a t $13,725 (Lee, 1988) although i t s h o u l d be noted t h a t b u i l d i n g c o s t s are h i g h l y v a r i a b l e depending on m a t e r i a l and d e s i g n . Fromberg (1991) used wood framing and p o l y e t h l e n e sheets t o c o n s t r u c t a feed shed a t $1,920. The two c o s t s a r e assumed i n the CGSS. The s a l v a g e v a l u e and expected l i f e expectancy o f the b u i l d i n g i s $3000.00 and 15 y e a r s . The r e s p e c t i v e v a l u e s f o r the s t o r a g e shed are $400.00 and 10 y e a r s . 4.7.1.3 Generator Although the FVR s i t e s i n t h i s study are assumed t o be on the B.C. Hydro power g r i d the farm must be prepared f o r power f a i l u r e s . A f i v e k i l o w a t t d i e s e l g e n e r a t o r has a c c o r d i n g l y been i n c l u d e d w i t h a p r i c e s e t a t $6,000 ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1989). The g e n e r a t o r has no salvage v a l u e and expected l i f e expectancy o f 10 y e a r s . 4.7.1.4 Water Pump A water pump i s necessary i n s i t u a t i o n s where g r a v i t y -a s s i s t e d flow i s not a v a i l a b l e . A water pump w i t h a c a p a c i t y of 700-1000 1/min has been i n c l u d e d a t a c o s t o f $3126 ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991). A t y p i c a l pump e f f i c i e n c y o f 0.75 i s assumed (Wheaton, 1985). The pump has no sal v a g e v a l u e and an expected l i f e span of 3 y e a r s . 40 4.7.1.5 PVC P i p i n g Each FVR u n i t has two 6.4 cm PVC p i p e s d i r e c t i n g the i n p u t water flow. The c o s t of t h i s p i p e i s $9.88 per meter ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991). The amount of p i p e needed i s determined from the i n p u t s , d i s t a n c e from source and e l e v a t i o n from source (see s e c t i o n 4.1). The PVC i s assumed t o have no salvage v a l u e and a l i f e expectancy o f 5 y e a r s . 4.7.1.6 Boat and S k i f f Both a crew work boat and an aluminum s k i f f are necessary t o perform r o u t i n e o p e r a t i o n s and maintenance on any marine farm. The c o s t of a 12 f t aluminum boat i s s e t a t $2,433. The p r i c e o f a l a r g e r 18 f t aluminum s k i f f would be $12,623 ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991). The s a l v a g e v a l u e and expected l i f e expectancy of the boat i s $300.00 and 10 y e a r s . The r e s p e c t i v e v a l u e s f o r the s k i f f are $1262.00 and 10 y e a r s . 4.7.1.7 D i v i n g . Laboratory and M i s c e l l a n e o u s Eguipment D i v i n g equipment al l o w s compulsory i n s p e c t i o n and maintenance of a l l underwater f a c i l i t i e s . The c o s t o f two dry s u i t s and accompanying equipment i s s e t a t $3,299. B a s i c l a b o r a t o r y equipment t o m a i n t a i n h e a l t h and water q u a l i t y are expected. The c o s t o f t h i s equipment i s s e t a t $5,000 (Lee, 1988; M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1989). M i s c e l l a n e o u s equipment such as d i p nets, power t o o l s and hand t o o l s are necessary f o r r o u t i n e o p e r a t i o n o f the farm. An average c o s t f o r these are $2,950 (Lee, 1988). None o f the above items has a f i x e d s a l v a g e p r i c e . The expected l i f e spans of the items are 3, 5 and 10 y e a r s , r e s p e c t i v e l y . 4.7.2 D i r e c t O p e r a t i n g Costs The f a c t o r s t h a t c o n t r i b u t e t o d i r e c t o p e r a t i n g c o s t s a r e : feed, eggs, e l e c t r i c i t y , oxygen, v e t e r i n a r y s u p p l i e s , SCUBA a i r f i l l s . 4.7.2.1 Cost of Feed The a c t u a l c o s t of feed can v a r y g r e a t l y e s p e c i a l l y under c o n d i t i o n s where hand-feeding accounts f o r f i s h response (Malamus, 1991). For the purposes o f p r o j e c t i o n s , however, i t i s assumed t h a t the feed amounts w i l l f o l l o w Moore-Clarke f e e d i n g c h a r t s as s t a t e d i n s e c t i o n 4.4. The c o s t o f feed (FEED) can then be determined as FEED = c o s t / k g feed * t o t a l f e e d consumed (kg) The c o s t o f feed i s s e t a t $1.25/kg ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991). 42 4.7.2.2 Cost o f Eggs The c o s t o f eggs i s assumed t o be $400.00 d o l l a r s per l i t r e o f eggs ( B j o r n d a l , 1990). Each l i t e r o f A t l a n t i c salmon eggs c o n t a i n s approximately 4000 i n d i v i d u a l eggs. 4.7.2.3 Cost o f E l e c t r i c i t y The c o s t o f e l e c t r i c i t y (ELEC) i s based on the sum o f a l l the pumping c o s t s f o r each month (t) of the p r o d u c t i o n c y c l e as f o l l o w s : 18 ELEC = $/KWhr * S POW (23) t=0 where, i n t h i s case t=18 and, POW = Q Y H ^ M P E F F H T = t o t a l o f head l o s s e s (m) MPEFF = motor/pump e f f i c i e n c y (0.75) Q = water flow 1/hr Y = s p e c i f i c weight o f water (N/m3) The p r i c e o f e l e c t r i c i t y i s f i x e d a t $.057/KWhr and i t i s assumed t h a t the motor and pump e f f i c i e n c y a re both 0.75 (Wheaton, 1985). 43 4.7.2.4 Cost o f M e d i c a t i o n and V e t e r i n a r y S e r v i c e Lee (1988) determined the average c o s t s f o r f i s h m e d i c a t i o n and v e t e r i n a r y s e r v i c e a t e i g h t d i f f e r e n t B.C. farm s i t e s . T h i s c o s t i s thus f i x e d a t $.08/kg o f f i s h a t h a r v e s t . 4.7.2.5 Cost o f A i r F i l l s In t h i s study a t l e a s t one d i v e per week i s assumed t o be necessary t o m a i n t a i n and i n s p e c t the FVR. The p r i c e o f an a i r f i l l i s s e t a t $5.00. For the e n t i r e p r o d u c t i o n c y c l e a i r f i l l c o s t w i l l be f i x e d a t $360. 4.7.3 I n d i r e c t O p e r a t i n g Costs I n d i r e c t c o s t s a r i s e from work t h a t i s b e n e f i c i a l t o the farm o r not d i r e c t l y a t t r i b u t a b l e t o smolt p r o d u c t i o n . I n c l u ded i n the i n d i r e c t o p e r a t i n g c o s t s a r e : m o r t a l i t y i n s u r a n c e , f i n a n c i n g c o s t , d e p r e c i a t i o n , l a b o u r and maintenance and t e s t i n g . 4.7.3.1 M o r t a l i t y Insurance The premiums f o r m o r t a l i t y i nsurance are based on the expected h a r v e s t v a l u e m u l t i p l i e d by an in s u r a n c e r a t e o f .04 (Lee, 1988). 44 4.7.3.2 F i n a n c i n g I n t e r e s t w i l l accrue on the s t a r t - u p c o s t , o r c a p i t a l c o s t , a t an annual r a t e t h a t can be s e t by the us e r . For t h i s study the i n t e r e s t r a t e i s a r b i t r a r i l y s e t a t 15% per annum. 4.7.3.3 Management Cost The management c o s t i s the s a l a r y o f the owner/operator o f the f i s h farm. T h i s amount w i l l be a r b i t r a r i l y s e t a t $55,000.00. 4.7.3.4 D e p r e c i a t i o n D e p r e c i a t i o n i s c a l c u l a t e d simply as the s t r a i g h t - l i n e method which i s an i n v e r s e f u n c t i o n o f the l i f e s p a n o f the equipment (Lee, 1988) such t h a t : D = IC - sv LY where D = D e p r e c i a t i o n c o s t IC = I n i t i a l c o s t SV = Salvage v a l u e LY = Expected l i f e o f equipment (years) 4.7.3.5 Cost of Labour The c o s t o f la b o u r i s based on 1 l a b o u r e r w i t h a monthly wage o f $1,500 ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1989). The l a b o u r i n c l u d e s job f u n c t i o n s such as s t o c k i n g , f e e d i n g , h a r v e s t i n g and t r a n s p o r t i n g of f i s h ; 4.7.4 Net O p e r a t i n g Revenues The Net O p e r ating Revenue (NOR) i s determined by the p roduct o f number o f smolts s o l d and the v a l u e per smolt ( t o t a l revenue) minus the t o t a l c o s t w i t h i n a c y c l e . The number and s i z e of smolts produced i s c a l c u l a t e d by the b i o l o g i c a l system (see s e c t i o n 4.2). The v a l u e of the smolt i s t y p i c a l l y s e t by the market. C u r r e n t l y 50-60 gram A t l a n t i c salmon smolts s e l l f o r $3.50 per smolt ( M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991). 4.7.5 Net Cash Flow The Net Cash Flow (NCF) of a h a t c h e r y system can be c a l c u l a t e d by s u b t r a c t i n g the c o s t s of p r o d u c t i o n from the t o t a l revenue from the s a l e of smolts ( A l l e n e t . a l . , 1984; B j o r n d a l , 1988 and B j o r n d a l , 1990). The c o s t o f l o s t o p p o r t u n i t i e s , i . e . i n t e r e s t on o p e r a t i n g and c a p i t a l c o s t s and o p e r a t o r l a b o u r and management, i s c o n s i d e r e d i n t h i s c a l c u l a t i o n ( M i n i s t r y of A g r i c u l t u r e and F i s h e r i e s , 1989). Hatchery systems t h a t v a r i a b l y a f f e c t these component c o s t s w i l l d i r e c t l y a l t e r the NCF ( S c h u e l l e r and K r u t z , 1989). 46 4.7.6 Break-Even P e r i o d The break-even p e r i o d i s the c y c l e i n which the NCF i s p o s i t i v e and a s u r p l u s o f cash i s e s t a b l i s h e d . The t o t a l revenue w i l l c o n s i s t e n t l y exceed the t o t a l c o s t s o f farm o p e r a t i o n and s t a r t - u p . 5.0 SPREADSHEET VALIDATION AND PARAMETER ESTIMATION Simulated experiments performed on the CGSS were f i r s t conducted t o compare t o the a c t u a l data accumulated from and a t the two aforementioned FVR farm s i t e s . T h i s i s the p rocess o f v a l i d a t i o n . More s p e c i f i c a l l y the p h y s i c a l c h a r a c t e r i s t i c s t h a t d e f i n e the FVR system ( i . e . the h e i g h t o f f r e s h water above the s a l t water datum) are compared t o the computed v a l u e s . T h i s s p e c i f i c p rocess i s parameter e s t i m a t i o n . F i s h growth, oxygenation and flow r a t e , changes i n the f reshwater h e i g h t above the s a l t w a t e r datum (HSD), and s t a b i l i t y and t u r g i d i t y of the FVR were i n v e s t i g a t e d and compared t o a c t u a l d ata. These i n v e s t i g a t i o n s generated output and parameter e s t i m a t i o n s t h a t f u r t h e r r e s o l v e d the s i m u l a t e d FVR system. The r e s u l t s from t h e s e i n i t i a l i n v e s t i g a t i o n s were used as r e v i s e d i n p u t s . The CGSS was p r o v i d e d w i t h a growth c o e f f i c i e n t and p r o d u c t i o n c y c l e t h a t emulated A t l a n t i c salmon growth r a t e s , otherwise i t was g i v e n i n p u t s t h a t r e f l e c t e d the Agammemnon farm s i t e . These were: 47 1) temperature regime -averaged monthly temperatures of t he FVR i n Agamemnon Channel 2) growth c o e f f i c i e n t (Gc) - 0.675 3) i n i t i a l smolt number - 50,000 4) i n i t i a l smolt mass - 0.2 g 5) l e n g t h o f p r o d u c t i o n c y c l e - 18 months 6) decimal f r a c t i o n m o r t a l i t y r a t e - 0.20 7) dimensions o f a f r u s t r u m F V R - top diameter 6.2 m, bottom diameter 4.2 m, depth 4.75 m 8) c u r r e n t speed - 0.5 m/s 9) i n f l u e n t oxygen c o n c e n t r a t i o n - 11 mg/1 10) oxygenation (Yes) 11) s a l t and freshwater s a l i n i t y - 24 ppt, 0 ppt, r e s p e c t i v e l y 12) d i s t a n c e from water source - 1400 m 13) e l e v a t i o n o f source - 130 m 14) flow r a t e - 300 1/min 15) g r a v i t y flow o r pump (Gr a v i t y ) 5.1 Growth Rates Two P a c i f i c salmon growth models (Eq. 2 and Eq. 5) were compared t o determine which would b e t t e r v a l i d a t e A t l a n t i c salmon growth r a t e s . Through i t e r a t i o n , E q u a t i o n 5 p r o v i d e d the b e s t f i t A t l a n t i c salmon growth i f G c was 0.675. 48 E q u a t i o n (2) was compared t o eq u a t i o n (5) i n F i g u r e 5. Both models have a v e r y s i m i l a r growth curve t h a t have an e x p o n e n t i a l e x p r e s s i o n w i t h i n c r e a s i n g time. Both Equation (2) and (5) were developed from Oncorhynchus spp. growth data. However, a d j u s t i n g the growth c o e f f i c i e n t , as suggested by Iwama and F i d l e r (1989), allowed Equation (5) t o more c l o s e l y f i t A t l a n t i c salmon growth r a t e s . An adjustment o f the growth c o e f f i c i e n t t o 0.675 i n equ a t i o n (5) c l o s e l y approximated A t l a n t i c salmon growth r a t e s of 45 grams i n twelve months, 365 days, ( L a i r d and Needham, 1989) and i n 70 grams ( B j o r n d a l , 1990) i n f i f t e e n months, 450 days ( F i g . 6). Equation (2) s i g n i f i c a n t l y o v e r e s t i m a t e d f i s h mass w i t h r e s p e c t t o a 12-15 month (365-450 days) A t l a n t i c salmon growth p e r i o d . 5.2 Oxygenation and Flow Rate A t the Agammenon FVR s i t e supplemental oxygen had been used t o m a i n t a i n the oxygen s a t u r a t i o n of the c u l t u r e water. I n f l u e n t flow r a t e s , Q, were l i m i t e d t o 150 and 300 1/min. CGSS t e s t s were performed t o determine the oxygen needs f o r a s i m u l a t e d Agammemnon FVR u n i t a t the i n f l u e n t water flow r a t e s o f 150 and 300 1/min. When the parameter "Q" i s l i m i t e d t o a c t u a l flows the CGSS v a l i d a t e d the need f o r supplementary oxygen ( F i g . 7 ) . 49 300 250 ^ 2 0 0 CO £ 3 150 CO CO o 2 100 50 0 Time (days) - • - Iwama (GC=1) - s - Stauffer F i g u r e 5 . A C o m p a r i s o n Between E q u a t i o n (5) (Iwama) and E q u a t i o n ( 2 ) ( S t a u f f e r ) a s Growth M o d e l s . 50 300 Time (days) Iwama (GC=.675) - s - Stauffer F i g u r e 6. A Comparison Between Eq u a t i o n (2) ( S t a u f f e r ) and E q u a t i o n (5) (Iwama) Growth Models w i t h a G c o f 0.675 i n Eq u a t i o n (5). 51 5.3 Changes i n Head The p r e d i c t e d HSD v a r i e d between 0.094-0.097 m. I t was not s i g n i f i c a n t l y d i f f e r e n t than the HSD a t the Agamemnon FVR s i t e (0.105 m) and f e l l w i t h i n the range o f the documented HSD, 0.03-0.10 m (Martin and Heard, 1987). Screen f r i c t i o n l o s s (SFL) was expected but the e x t e n t of the f r i c t i o n was u n c e r t a i n . The a c t u a l HSD (h i n Eq. 9) a t the Agamemnon FVR s i t e was used i n the CGSS t o c a l c u l a t e SFL (±H) and the s c r e e n drag c o e f f i c i e n t C (see Eg. 7 and Eq. 10). The parameter C was determined t o be 9.28E05. A t a flow r a t e o f 150 1/min the s c r e e n f r i c t i o n component o f HSD i s approximately 0.006 m and i s r e l a t i v e l y u n v a r y i n g w i t h r e s p e c t t o the HSD ( F i g . 8 ) . The f o r c e a g a i n s t the s c r e e n and l i n e r , a s s o c i a t e d w i t h t h i s h e i g h t i s 1041 N. 6.0 SPREADSHEET ANALYSIS From v a l i d a t e d and estimated model parameters determined i n the p r e v i o u s s e c t i o n the t e c h n i c a l and economic output of the CGSS was analyzed. Design c r i t e r i a f o r t e c h n i c a l f e a s i b i l i t y a re determined from the spreadsheet behaviour. The economic f e a s i b i l i t y i s determined through the a n a l y s i s of farm case s t u d i e s . 6.1 Spreadsheet Behaviour Inputs of the CGSS were v a r i e d t o determine how t h i s v a r i a t i o n e f f e c t s system outputs. By a n a l y z i n g the output of t h i s v a r i a t i o n i t i s p o s s i b l e t o generate p r e l i m i n a r y FVR 52 2.5 600 Time (days) 150 l/min - + — 300 l/min 600 l/min Figure 7 . The Amount o f Oxygenation Needed Throughout a T y p i c a l P r o d u c t i o n C y c l e when the I n f l u e n t Flow Rate i s L i m i t e d t o 150, 3 00, and 600 1/min as P r e d i c t e d by the CGSS. 53 0.097 0.097 0.093-300 Time (days) -0.005 600 SFL -e- HSD F i g u r e 8. A Comparison Between the Height o f F r e s h Water Above the S a l t Water Datum (HSD) and the C o n t r i b u t i n g P o r t i o n o f which i s A t t r i b u t e d t o the Screen F r i c t i o n Loss (SFL). 54 d e s i g n c r i t e r i a . I n f l u e n t flow r a t e and c u r r e n t v e l o c i t y are two i n p u t s t h a t may a f f e c t the FVR o p e r a t i o n i n terms o f supplemental oxygen and s t a b i l i t y and t u r g o r . 6.1.1 I n f l u e n t Flow Rate and Oxygenation A CGSS t e s t run allowed the i n f l u e n t flow r a t e t o change w i t h the i n c r e a s i n g r e s p i r a t i o n needs o f the growing f i s h . G e n e r a l l y the flow r a t e s i n c r e a s e d w i t h i n c r e a s i n g f i s h biomass ( F i g . 9 ) . The r e l a t i o n s h i p between i n c r e a s i n g biomass and flow r a t e i s s i g m o i d a l . T h i s i s p a r t i a l l y an a r t i f a c t of the y e a r l y temperature regime. The i n i t i a l maximum i s an a d d i t i v e r e s u l t o f the i n c r e a s e d f i s h r e s p i r a t i o n and depressed s o l u b i l i t y of oxygen i n water d u r i n g the warmer summer months. The sharp p o s i t i v e s l o p e i n the l a t t e r stages of the graph r e f l e c t s an i n c r e a s i n g flow demand by the smolt crop as they move i n t o a second summer of growth. Spreadsheet t e s t s t o q u a n t i f y f i s h oxygen needs were run a t t h r e e i n f l u e n t water flow r a t e s , 150, 300 and 600 1/min ( F i g . 7 ) . At an i n f l u e n t flow r a t e o f 150 1/min oxygenation i s needed 160 days i n t o the c y c l e . Oxygen needs i n c r e a s e i n t o the f i r s t summer t o 5.0E05 mg/kghr. The need then decreases s l i g h t l y over the w i n t e r and subsequently i n c r e a s e s t o 2.0E06 mg/kghr as the water temperature i n c r e a s e s i n the second season. The t e s t a t a flow r a t e of 300 1/min p a r a l l e l s the 150 1/min p r o f i l e w i t h p r o p o r t i o n a t e l y l e s s oxygen needs. T h i s t e s t i n d i c a t e d t h a t oxygenation was r e q u i r e d 180 days 55 Biomass (kg) (Thousands) F i g u r e 9. The R e l a t i o n s h i p of U n l i m i t e d I n f l u e n t Flow Rate f o r I n c r e a s i n g F i s h Biomass as P r e d i c t e d by the CGSS. i n t o the p r o d u c t i o n c y c l e . At an i n f l u e n t flow r a t e of 600 1/min oxygenation appears t o be needed f o r a two month p e r i o d c o i n c i d i n g w i t h the warmer summer waters and then not a g a i n u n t i l day 420 when the t o t a l crop biomass begins t o i n c r e a s e q u i c k l y and warmer water temperatures r e o c c u r . The n e g a t i v e v a l u e s i n F i g u r e 9 are an a r t i f a c t of the computation and should be i n t e r p r e t e d as zero oxygenation requirements. These t e s t runs i n d i c a t e d t h a t s p e c i f i c oxygenation s t r a t e g i e s should be expected under d i f f e r e n t flow c o n d i t i o n s . Current farmers have had l o s s e s due t o the i n a b i l i t y t o q u i c k l y respond t o oxygen d e f i c i e n c i e s . 6.1.2 Changes i n Head The h e i g h t above the s a l t w a t e r datum (HSD) o f the freshwater i n the FVR s i m u l a t i o n v a r i e s between 0.094 and 0.097 m over the p r o d u c t i o n c y c l e f o r a FVR u n i t volume of 100 m3 ( F i g . 8) . The s i n u s o i d a l shape of F i g . 8 r e f l e c t s the e f f e c t s of temperature on the d e n s i t y of freshwater and s a l t w a t e r . The HSD i s t h e o r e t i c a l l y the r e s u l t o f 3 components: f l u i d v e l o c i t y , f r i c t i o n a l f o r c e s and r e l a t i v e s p e c i f i c weight (Eq. 9 ) . The f r i c t i o n f o r c e s can be from two s o u r c e s : l i n e r f r i c t i o n and s c r e e n f r i c t i o n . At a water flow r a t e of 150 1/min the v e l o c i t i e s through the FVR u n i t , a t t h e i n l e t and o u t l e t areas, are v e r y low, 1.79E-4 m/s and 2.63E-4 m/s r e s p e c t i v e l y . Consequently the v e l o c i t y component o f head and 57 the l i n e r f r i c t i o n can be c o n s i d e r e d n e g l i g i b l e under such flow regimes. T e s t s runs were performed w i t h the CGSS t o i n v e s t i g a t e the e f f e c t s on the HSD i f water flow r a t e s were i n c r e a s e d ( F i g . 10). At a flow r a t e o f 1000 1/min a HSD o f 0.10 m was p r e d i c t e d as confirmed by M a r t i n and Heard (1987). At h i g h e r flow r a t e s the HSD i n c r e a s e d w i t h more p o s i t i v e s l o p e s t o 2.2 m a t 7800 1/min. I f such flow r a t e s were t o be used i n a FVR u n i t the s c r e e n and surrounding l i n e r would have t o be designed t o support the f o r c e s a s s o c i a t e d w i t h such a HSD. 6.1.3 S t a b i l i t y and T u r g i d i t y The v a l u e s o f CG, CB and MC (Table II) show t h a t CG remains between CB and MC thereby s a t i s f y i n g the c r i t e r i a f o r s t a b i l i t y (see s e c t i o n 4.5.3). Under s h e l t e r e d c o n d i t i o n s t y p i c a l o f most f i s h farm c o n d i t i o n s i n B.C. any o f the f o u r shapes c o n s i d e r e d c o u l d p r o v i d e s t a b l e e q u i l i b r i u m . Table I I . The Center o f Buoyancy (CB), Center o f G r a v i t y (CG) , and Metacenter (MC) D e f i n i n g S t a b i l i t y f o r Four D i f f e r e n t Shapes. Shape  Center Frustrum Cuboid Hemisphere Pa r a b o l a CB (m) 2.333 2.455 3.069 3.274 CG (m) 2.376 2.546 3.125 3.333 MC (m) 4.341 3.066 8.018 6.360 58 ° 0 1000 2000 3000 4000 5000 6000 7000 8000 Flow (l/min) F i g u r e 10.The R e l a t i o n s h i p Between U n l i m i t e d I n f l u e n t Flow Rate and the Height Above the S a l t Water Datum (HSD) as P r e d i c t e d by the CGSS. 59 The f o r c e s e x e r t e d on e i t h e r s i d e o f a fr u s t r u m were c a l c u l a t e d over the p r o d u c t i o n c y c l e . The g r e a t e r f o r c e on the i n s i d e i s accounted f o r by the freshwater head. T h i s f o r c e m a i n t a i n s the t u r g i d i t y o f the l i n e r . F i g u r e 11 i s the r e s u l t s o f a s i m u l a t i o n t h a t i l l u s t r a t e s the r e l a t i o n s h i p between the d i f f e r e n c e o f the i n e r t i a l f o r c e s o f d i f f e r e n t shaped FVR u n i t s and the a s s o c i a t e d drag f o r c e e x e r t e d on these d i f f e r e n t shapes by a s e t o f c u r r e n t v e l o c i t i e s . The top diameter o f the u n i t s were s e t a t 6 meters and the depth o f the u n i t s 5 meters. A n a l y s i s o f the p r o f i l e s i n d i c a t e t h a t a fru s t r u m w i l l b e g i n l o s e t u r g i d i t y a t c u r r e n t speeds o f 1.1 m/s, a cuboid a t 1.15 m/s, a p a r a b o l o i d a t 1.2 m/s and a hemisphere a t n e a r l y 1.6 m/s. With the s t a t e d dimensions and a t g r e a t e r r e s p e c t i v e c u r r e n t v e l o c i t i e s a d d i t i o n a l mooring mass would be r e q u i r e d t o m a i n t a i n FVR t u r g o r . The d e c r e a s i n g s l o p e w i t h i n c r e a s i n g c u r r e n t v e l o c i t i e s r e f l e c t s the drag c o e f f i c i e n t s dependency on the square o f the c u r r e n t v e l o c i t y (Eq. 21). The f a c t t h a t the FVR t u r g i d i t y can be p r e d i c t e d by the CGSS has important s i t e s e l e c t i o n i m p l i c a t i o n s . For i n s t a n c e , a f r u s t r u m shaped l i n e r i n areas w i t h c u r r e n t v e l o c i t i e s g r e a t e r than 1.1 m/s would be u n s u i t a b l e . Many areas on the B r i t i s h Columbia c o a s t l i n e have r e g u l a r c u r r e n t v e l o c i t i e s g r e a t e r than 1.1 m/s (Thomson, 1981). 60 J T 1 1 1 1 1 1 1 1 1 1 0 . 0 0 . 4 0 . 8 1 . 2 1 . 6 2 . 0 Current Speed (m/s) frustrum —±— hemisphere —s— paraboloid -s— cuboid F i g u r e 11.A Comparison Between the I n e r t i a l and Drag Force D i f f e r e n c e s o f 4 FVR Shapes I n d i c a t i n g the Cu r r e n t V e l o c i t y C r i t e r i a f o r L i n e r Turgor. 61 6.2 Case S t u d i e s The CGSS parameters and t e c h n i c a l d e s i g n c r i t e r i a were e l u c i d a t e d from: 1) the Agamemnon FVR s i t e ; 2) the Ala s k a n FVR (Mar t i n and Heard, 1987); 3) spreadsheet v a l i d a t i o n ; and 4) spreadsheet behaviour. With t h i s i n f o r m a t i o n farm case s t u d i e s were analyzed f o r economic f e a s i b i l i t y . The base case i n v e s t i g a t e d was a v a r i a t i o n o f the Agamemnon FVR s i t e . The second and t h i r d cases were v a r i a n t s of t h i s base farm t h a t a re c o n s i d e r e d r e p r e s e n t a t i v e f o r oth e r p o t e n t i a l farm s i t e s i n B r i t i s h Columbia. Economic assumptions t h a t h o l d common t o a l l cases a re: 1) an i n i t i a l smolt p r i c e o f $3.50 d e c l i n i n g by 5% i n every subsequent p r o d u c t i o n c y c l e 2) FVR r u b b e r i z e d l i n e r c o s t o f $45.21 /m2 3) b u i l d i n g and shed c o s t o f $16,450.00 4) f l o a t and mooring c o s t per u n i t o f $6,500.00 5) water pump c o s t o f $3126.00 6) feed c o s t o f $1.25 /kg 7) l a b o u r c o s t o f $36,000.00 / y e a r 8) an e l e c t r i c i t y c o s t o f $0.0276 /KWhr 9) a s t a r t - u p l o a n a t an i n t e r e s t o f 15% / y e a r 10) s t r a i g h t - l i n e d e p r e c i a t i o n 11) l e a s e and l i c e n s e f e e s o f $1025.00 / y e a r 62 6.2.1 The Base Farm The base farm was analyzed u s i n g the t e c h n i c a l i n p u t s as l i s t e d i n s e c t i o n 5.0 and economic i n p u t s as l i s t e d above. T a b l e I I I i s the economic output from the base farm s i m u l a t i o n . The Net Cash Flow (NCF) i s n e g a t i v e f o r a l l but the f i r s t p r o d u c t i o n c y c l e . T h i s i s so because the s e l l i n g p r i c e o f the A t l a n t i c smolt i s s e t a t $3.50 i n the f i r s t h a r v e s t c y c l e and i s assumed t o d e c l i n e i n v a l u e by 5% f o r every subsequent p r o d u c t i o n c y c l e . As w e l l , not enough smolt revenue i s o b t a i n e d t o o f f s e t the c o s t s i n c u r r e d f o r c a p i t a l and o p e r a t i n g c o s t s f o r t h i s farm s c e n a r i o . The o n l y revenue source i s the s a l e o f smolts. The spreadsheet was used t o determine the r e l a t i o n s h i p between NCF and the i n i t i a l number of smolts assuming a 20% m o r t a l i t y r a t e ( F i g . 13). For 50,000 smolts the NCF goes n e g a t i v e i n the second c y c l e and c o n t i n u e s t o decrease through f u r t h e r p r o d u c t i o n c y c l e s . Both the s t o c k i n g o f 75,000 and 100,000 smolts m a i n t a i n s a p o s i t i v e NCF. The g e n e r a l d e c l i n e i n a l l the cases i s due t o both the d e c r e a s i n g s e l l i n g p r i c e o f the A t l a n t i c smolt and the a f f e c t s o f i n f l a t i o n . The r e l a t i o n s h i p between NCF and the number o f smolts s t a r t e d was a l s o c o n s i d e r e d ( F i g . 14) . T o t a l payback, as i n d i c a t e d by p o s i t i v e cash flow, i s h i g h l y dependent on the number o f smolts s t a r t e d . A g e n e r a l t r e n d toward sooner payback p e r i o d s appears as the number o f s m o l t - s t a r t s i n c r e a s e . Any smolt s t a r t s between 50,000 and 100,000 a l l o w 63 payback t o be achieved w i t h i n the f i r s t c y c l e . By the s i x t h c y c l e a t l e a s t 80,000 smolts must be s t a r t e d t o achieve payback o f the i n i t i a l investment. 6.2.2 Farm Case 2 A l l economic assumptions are as s t a t e d i n s e c t i o n 6.2 above and, w i t h the e x c e p t i o n of the f o l l o w i n g i n p u t changes, t e c h n i c a l assumptions are as s t a t e d i n s e c t i o n 5.0: 1) i n i t i a l numbers- 100,000 f i s h 2) d i s t a n c e from water source- 1000 m 3) e l e v a t i o n o f source- -5 m 4) l e n g t h of p r o d u c t i o n c y c l e - 15 months 5) g r a v i t y flow or pump- (pump) T h i s s c e n a r i o brought the i n i t i a l number o f smolts t o 100,000 i n o r d e r t o c r e a t e a p o s i t i v e NCF as suggested by the p r e v i o u s s i m u l a t i o n . The water source now, however, was t o be pumped t o the FVR t o t e s t the e f f e c t o f pumping c o s t s . The NCF remains p o s i t i v e through s i x c y c l e s (Table I V ) . The e l e c t r i c i t y c o s t of pumping water f o r t h r e e c y c l e s i s 0.36%, 0.37% and 0.38% of the t o t a l c o s t s , r e s p e c t i v e l y (Table V) . Furthermore, oxygenation c o s t s are c o n s i d e r a b l y lower a t .05% o f t o t a l c o s t s f o r the same t h r e e c y c l e s (Table V ) . In comparison t o o t h e r c o s t s such as PVC, feed and labour, e l e c t r i c i t y and oxygen c o s t s are i n s i g n i f i c a n t . PROFORM CYCLE 0 1 2 3 4 5 (+)TOTAL REVENUES $139,999.88 $132,999.89 $125,999.89 $118,999.90 $111,999.90 DOP/IDOP COSTS DEPRECIATION $136,484.42 $22,864.00 $140,186.27 $22,864.00 $145,66156 $22,864.00 $172,644.77 $22,864.00 $165,990.20 $22,864.00 (-)TOTAL COSTS $159,348.42 $163,050.27 $168,526.56 $195,508.77 $188,854.20 (=)NETOPER REVENUE (-)TAXES ($19,348.54) $0.00 ($30,050.38) $0.00 ($42,526.67) $0.00 ($76,508.87) $0.00 ($76,854.29) $0.00 (=)INCOME AFTER TAXES ($19,348.54) ($30,050.38) ($42,526.67) ($76,508.87) ($76,854.29) (+)DEPRECIATION $22,864.00 $22,864.00 $22,864.00 $22,864.00 $22,864.00 (=)NET CASH FLOW $3,515.46 ($7,186.38) ($19,66167) ($53,644.87) ($53,990.29) CUM SURPLUS/DEFICI ($142,437.54) ($138,922.08) ($146,108.45) ($165,771.12) ($219,415.99) ($273,406.28) 65 100 co o c (0 </) O 2 E -40 50,000 Smolt 75,000 Smolts 100,000 Smolts F i g u r e 12.The E f f e c t o f Stocked Smolt Numbers on the Net Cash Flow (NCF) f o r the Base Farm over 6 C y c l e s ( M o r t a l i t y = 20%). 66 100 Smolt Numbers (Thousands) Cycle 1 ' 2 3 e - 4 — x — 5 ~±r- 6 F i g u r e 13.The R e l a t i o n s h i p Between Net Cash Flow and Stocked Smolt Numbers over 6 P r o d u c t i o n C y c l e s f o r the Base Farm. PROFORM CYCLE 0 1 2 3 4 5 6 (+)TOTAL REVENUES $279,999.76 $265,999.77 $251,999.78 $237,999.80 $223,999.81 $209,999.82 DOP/1DOP COSIES DEPRECIATION $141,815.89 $19.70140 $131,275.90 $19,70140 $131,639.89 $19,70140 $155,773.93 $19,70140 $141,177.90 $19,70140 $151,234.92 $19.70140 (-)TOTAL COSTS $161,518.29 $150,97a30 $151,34129 $175,476.33 $160,880.30 $170,937.32 (=)NET OPER REVENUE (-)TAXES $118,481.47 $39,098.89 $115,021.47 $37,957.09 $100,657.50 $33,216.97 $61523.47 $20,63174 $63,119.50 $20,829.44 $39,06150 $11890.62 (= )INCOME AFTER TAXES $79,38159 $77,064.39 $67,440.52 $41,890.72 $42,290.07 $26,171.87 ( + )DEPRECIATION $19,70140 $19,70140 $19,70140 $19,70140 $19,70140 $19,70140 (=)NET CASH FLOW $99,084.99 $96,766.79 $87,14192 $61,593.12 $61,99147 $45,874.27 CUM SURPLUS/DEFIC ($126,629.54) ($27,544.55) $69,22123 $156,365.16 $217,95a28 $279,950.75 $325,825.02 68 T a b l e V . The Percentage o f the T o t a l Cost p e r Smolt f o r D i r e c t O p e r a t i n g Costs (DOPCOS) over 3 P r o d u c t i o n C y c l e s f o r Farm Case 2. Production Cycle 1 2 3 Direct Operating Costs (%) Feed Delivery 0.61 0.63 0.66 Feed 8.42 8.76 9.11 Eggs 6.19 6.44 6.70 Electricity 0.36 0.37 0.38 Oxygen 0.05 0.05 0.05 Fuel 1.98 2.06 2.14 Veterinary 0.17 0.18 0.18 Air Fills 0.22 0.23 0.24 69 6.2.3 Farm Case 3 A l l assumptions are as s t a t e d i n s e c t i o n 5.5.2 above wi t h the e x c e p t i o n o f the f o l l o w i n g changes: 1) M o r t a l i t y r a t e of 40% 2) Shape- P a r a b o l o i d 3) d i s t a n c e from water source- 2000 m 4) e l e v a t i o n of s ource- -10 m The m o r t a l i t y r a t e has a d i r e c t e f f e c t on the number of h a r v e s t e d smolts. More i m p o r t a n t l y , because o f the h i g h e r economic investment, i n c r e a s e d or unforseen m o r t a l i t i e s i n l a t e r growth stages can s i g n i f i c a n t l y a f f e c t NCF. B j o r n d a l (1988) makes an economic a n a l y s i s of the a f f e c t s o f changing m o r t a l i t y r a t e s and unforeseen m o r t a l i t y . The e f f e c t of m o r t a l i t y r a t e on NCF was s i m i l a r l y emphasized i n t h i s s i m u l a t i o n , however the CGSS can not account f o r p e r i o d i c , or unforeseen m o r t a l i t y . At a r a t e o f 40% o n l y 60,000 smolts w i l l go t o market f o r a h a r v e s t v a l u e of $209,999.52 i n the f i r s t c y c l e (Table VI) . The NCF remains p o s i t i v e f o r the f i r s t t h r e e c y c l e s but then accumulates a d e f i c i t of $819.72 i n the f o u r t h c y c l e . Although the NCF i s u s u a l l y p o s i t i v e not enough income i s o b t a i n e d t o o f f s e t the accumulated d e f i c i t (Table V I ) . A s i m u l a t i o n was run t o determine th e r e l a t i o n s h i p between m o r t a l i t y r a t e and NCF ( F i g . 14). A g e n e r a l l i n e a r decrease of NCF w i t h i n c r e a s i n g m o r t a l i t y r a t e f o r a l l c y c l e s was found. The NCF does remain p o s i t i v e f o r the f i r s t t h r e e c y c l e s even when the m o r t a l i t y r a t e reaches 50%. However, f o r the f o u r t h through s i x t h c y c l e NCF i s n e g a t i v e i f the m o r t a l i t y r a t e i n c r e a s e s p a s t 40%. The shape of the FVR u n i t was changed t o a p a r a b o l o i d t h a t has a s u r f a c e t o volume r a t i o approximately 6 times h i g h e r than t h a t o f the frustrum. The t o t a l c o s t o f the l i n e r m a t e r i a l f o r a p a r a b o l o i d i s $23,919.94 (Table V I I ) , whereas the c o s t o f the f r u s t r u m l i n e r i n the farm case 2 i s o n l y $3,147.54 (Table V I I I ) . C l e a r l y the r e l a t i v e l y l a r g e the s u r f a c e area of the p a r a b o l o i d c o n t r i b u t e s s i g n i f i c a n t l y t o the c a p i t a l c o s t s . In farm case 3 both the d i s t a n c e from the water source and the e l e v a t i o n from the water source was i n c r e a s e d t o 2000 m and 10 m, r e s p e c t i v e l y . Even w i t h these i n c r e a s e s the e l e c t r i c i t y f o r pumping c o s t s was s t i l l i n s i g n i f i c a n t . P o l y v i n y l c h l o r i d e p i p i n g , on the o t h e r hand, a t 45.32% of the c a p i t a l c o s t s (Table V I I ) , i s a concern. The d i s t a n c e from the water source may a f f e c t the f e a s i b i l i t y o f the farm as a r e s u l t of PVC c o s t s . PROFORM CYCLE 0 1 2 3 4 5 (+)TOTAL REVENUES $209,999.52 $199,499.55 $188,999.57 $178,499.59 $167,999.62 DOP/1DOP COSTS DEPRECIATION $146,810.20 $27,606.40 $143,329.76 $27,606.40 $140,724.25 $27,606.40 $179,319.32 $27,606.40 $143,976.94 $27,606.40 (-)TOTAL COSTS $174,416.60 $170,936.16 $168^ 30.65 $206,925.72 $171,583.34 (=)NET OPER REVENUE (-)TAXES $35,582.92 $11,742.36 $28,563.38 $9,425.92 $20,668.92 $6,820.74 ($28,426.12) $0.00 ($3,583.72) $0.00 (=)INCOME AFTER TAXES $23,840.56 $19,137.47 $13,848.18 ($28,426.12) ($3,583.72) (+)DEPRECIATION $27,606.40 $27,606.40 $27,606.40 $27,606.40 $27,606.40 (=)NET CASH FLOW $51,446.96 $46,743.87 $41,454.58 ($819.72) $24,022.68 CUM SURPLUS/DEFICI ($186,921.94) ($135,474.99) ($88,731.12) ($47,276.54) ($48,096.27) ($24,073.58) 72 Mortality Rate (%) Cycle 1 —•— 2 3 - B - 4 - x - 5 A - 6 F i g u r e 14.The R e l a t i o n s h i p Between the Net Cash Flow and the M o r t a l i t y Rate over 6 P r o d u c t i o n C y c l e s f o r Farm Case 3. 73 T a b l e VII.Summary o f t h e S t a r t - U p C o s t s a n d P e r c e n t a g e o f T o t a l C o s t p e r S m o l t i n t h e F i r s t P r o d u c t i o n C y c l e f o r Farm C a s e 3. TOTAL COSTS Start-Up Costs % TC 1 Building $13, 725.00 7.87 Liner $23, 919.94 13.71 Float $10, 000.00 5.73 Mooring $13, 000.00 7.45 Storage Shed $1,920.00 1.10 Diving Equipment $3, 299.00 1.89 Lab Equipment $5, 000.00 2.87 Tools $2, 950.00 1.69 Diesel Generator $6, 000.00 3.44 Water Pump $3, 126.00 1.79 Aluminum Skiff $12, 623.00 7.24 Work Boat $2, 433.00 1.39 PVC Piping $79, 040.00 45.32 Boat Motors $9, 886.00 5:^ 7 74 T a b l e V I I I . Summary o f S t a r t - U p C o s t s a n d P e r c e n t a g e o f T o t a l C o s t s f o r S m o l t s i n F i r s t P r o d u c t i o n C y c l e f o r B a s e Farm 2. TOTAL COSTS Start-Up Costs % TC 1 Building $13, 725.00 8.50 Liner $3, 147.54 1.95 Float $10, 000.00 6.19 Mooring $13, 000.00 8.05 Storage Shed Jl , 920.00 1.19 Diving Equipment $3, 299.00 2.04 Lab Equipment $5, 000.00 3.10 Tools $2, 950.00 1.83 Diesel Generator $6, 000.00 3.71 Water Pump $3, 126.00 1.94 Aluminum Skiff $12, 623.00 7.82 Work Boat $2, 433.00 1.51 PVC Piping $39, 520.00 24.47 Boat Motors $9, 886.00 6.12 75 7.0 CONCLUSIONS A CGSS of a f l o a t i n g v e r t i c a l raceway f o r A t l a n t i c salmon smolt p r o d u c t i o n was developed d u r i n g the course o f t h i s study. The spreadsheet mathematically d e s c r i b e d the FVR i n terms o f b i o l o g i c a l , p h y s i c a l and economic parameters. F r e s h water v e r t i c a l raceway s i m u l a t i o n s were v a l i d a t e d w i t h data from two a c t u a l FVR s i t e s . The CGSS was analyzed t o determine c o n d i t i o n s t h a t would p r o v i d e a t e c h n i c a l l y and e c o n o m i c a l l y f e a s i b l e smolt p r o d u c t i o n u n i t t h a t would u t i l i z e e x i s t i n g marine r e a r i n g space. T e s t s v a l i d a t e d the c o n c l u s i o n t h a t flow r a t e s t y p i c a l o f one l o c a l FVR farm, 150, 300 and 600 1/min, w i l l r e s u l t i n oxygen d e f i c i e n c i e s d u r i n g the p r o d u c t i o n c y c l e . These oxygen d e f i c i e n c i e s occur most r e g u l a r l y d u r i n g the warmer summer months, 160, 180 and 210 days i n t o the p r o d u c t i o n c y c l e , r e s p e c t i v e l y . By a n t i c i p a t i n g o x y g e n - d e f i c i e n t p e r i o d s the farmer w i l l have time t o o b t a i n and apply supplemental oxygen. A range o f i n f l u e n t flow r a t e s were an a l y z e d t o determine the e f f e c t on the f r e s h water head, o r h e i g h t above s a l t water datum (HSD). For a c t u a l i n f l u e n t flow r a t e s the HSD p r e d i c t i o n s were c o n s i s t e n t w i t h the Agamemnon and Ala s k a n FVR s i t e s , approximately 0.10 m. However, i n f l u e n t flow r a t e s of 2000-7800 1/min i n c r e a s e the HSD from 0.2-2.2 m. An i n c r e a s i n g p r o p o r t i o n o f t h i s HSD i s a t t r i b u t e d t o f r i c t i o n a t the o u t l e t s c r e e n which may cause the sc r e e n and l i n e r t o f a i l . The spreadsheet s i m u l a t i o n demonstrated t h a t a FVR shaped as e i t h e r a frustrum, hemisphere, p a r a b o l o i d , o r cuboid, i s s t a b l e w i t h r e s p e c t t o c r i t e r i a d e f i n e d by the r e l a t i o n s h i p between the metacenter, c e n t e r of buoyancy and c e n t e r of g r a v i t y . For the f o u r shapes i n v e s t i g a t e d t h e c e n t e r of g r a v i t y remains between the c e n t e r o f buoyancy and the metacenter. Turgor, d e f i n e d as an e q u a l i t y between the c u r r e n t drag f o r c e s e x e r t e d on the FVR and the i n e r t i a l f o r c e s o f the FVR, w i l l be maintained f o r a l l f o u r shapes p r o v i d e d the c u r r e n t v e l o c i t i e s are not too l a r g e . I f the c u r r e n t v e l o c i t y i s not g r e a t e r than 1.1 m/s a f r u s t r u m w i l l remain t u r g i d . The same i s t r u e f o r a hemisphere, p a r a b o l o i d and c u b o i d i f c u r r e n t v e l o c i t i e s are not g r e a t e r than 1.6, 1.2 and 1.15 m/s, r e s p e c t i v e l y . With d e s i g n c r i t e r i a determined from the CGSS and a c t u a l farm s i t e s , t h r e e h y p o t h e t i c a l farm cases were t e s t e d and analyzed t o determine economic f e a s i b i l i t y . The net cash flow of t h e base farm remains n e g a t i v e a f t e r the f i r s t p r o d u c t i o n c y c l e break-even. T h i s farm case, however, assumed t h a t o n l y 50,000 smolts were s t a r t e d f o r a f a c i l i t y t h a t took the r e s p o n s i b i l i t y f o r complete s t a r t - u p c o s t s . Farm case 2 and smolt s t a r t s of 100,000 obt a i n e d a c o n s i s t e n t p o s i t i v e NCF. P o s i t i v e NCF i s h i g h l y dependent on the number o f smolts s o l d . Farm case 3 f o r the most p a r t r e t a i n s a p o s i t i v e NCF but income never g a i n s on the accumulating d e f i c i t . The 2 km d i s t a n c e from the f r e s h water source, and t h e r e f o r e the PVC p i p i n g c o s t (45.32%) i s an important f a c t o r a f f e c t i n g t h i s d e f i c i t . The smolt p r o d u c t i o n c o s t ranged from $1.37-$5.89. The c o s t o f $1.37 was achieved w i t h a smolt s t o c k i n g o f 100,000, a 20% r a t e and a 15 month p r o d u c t i o n c y c l e , i . e . farm case 2. For a l l t h r e e base farms the e l e c t r i c i t y c o s t s o f pumping (0.25-0.87%) and oxygenation c o s t s (0.01-0.07%) c o n t r i b u t e d l i t t l e t o the t o t a l c o s t s as compared t o l a b o u r (12.02-32.79%) and feed c o s t s (5.58-12.39%). I t can be concluded t h a t the spreadsheet developed d u r i n g t h i s study i s an e f f e c t i v e t o o l t o i n v e s t i g a t e a l t e r n a t i v e s of FVR p r o d u c t i o n s t r a t e g y , d e s i g n and economy. In summary, these c o n c l u s i o n s can been drawn: 1. Oxygen d e f i c i e n c y becomes a concern d u r i n g the p r o d u c t i o n c y c l e . 2. The CGSS enables the farmer t o p r e d i c t when supplemental oxygen i s r e q u i r e d t o m a i n t a i n f i s h oxygen demands. 3. At flow r a t e s of 150, 300 and 600 1/min, s c r e e n head l o s s i s i n s i g n i f i c a n t . 4. At h i g h e r flow r a t e s , 2000-7800 1/min, the f r i c t i o n a l f o r c e s a t the o u t l e t screen may s t r e s s the s c r e e n and s u r r o u n d i n g l i n e r , c a u s i n g l i n e r f a i l u r e . 5 . Under t y p i c a l p r o d u c t i o n c o n d i t i o n s the f o u r shapes c o n s i d e r e d w i l l p r o v i d e hydromechanical s t a b i l i t y . 78 6. For the c o n d i t i o n s c o n s i d e r e d , a c u r r e n t v e l o c i t y g r e a t e r than 1.1 m/s r e q u i r e s a d d i t i o n a l mooring weight t o m a i n t a i n FVR t u r g o r , depending on the shape o f the l i n e r . 7. The NFC i s p o s i t i v e and maintains a cumulative s u r p l u s o n l y f o r farm case 2, i . e . 100,000 smolts, 20% m o r t a l i t y r a t e and a 15 month p r o d u c t i o n c y c l e . NFC i s a f f e c t e d most by the l a c k o f smolt revenue i n farm case 1 and by the c o s t o f PVC p i p i n g (45.32%) i n farm case 3. 8. The lowest smolt p r o d u c t i o n c o s t was $1.37 achieved w i t h i n farm case 2. 9. In r e l a t i o n t o the c o s t of feed and l a b o u r , e l e c t r i c i t y and supplemental oxygen c o s t s are i n s i g n i f i c a n t . 8.0 FURTHER STUDY AND SUGGESTIONS The CGSS developed d u r i n g t h i s study i s the o n l y s i m u l a t i o n known t o date t h a t i n t e g r a t e s b a s i c e n g i n e e r i n g w i t h the t e c h n i c a l and economic f e a s i b i l i t y o f l o c a l l y a p p l i e d a q u a c u l t u r e t e c h n o l o g i e s . T h i s study i s n e c e s s a r i l y l i m i t e d i n scope t o s p e c i f i c i n v e s t i g a t i o n s o f the a s p e c t s o f one of these t e c h n o l o g i e s . The a q u a c u l t u r e i n d u s t r y would b e n e f i t from c o n t i n u e d study i n the a p p l i c a t i o n o f spreadsheet s i m u l a t i o n s t o b a s i c e n g i n e e r i n g problems i n aq u a c u l t u r e technology. More s p e c i f i c a l l y t h i s study p r o v i d e s a b a s i c t o o l t h a t can f u r t h e r i n v e s t i g a t e a l t e r n a t i v e FVR farm s i t e s , technology and economy. Some o f the i n v e s t i g a t i o n s t h a t may be c o n s i d e r e d a r e : 1) d e v e l o p i n g a more r e s o l u t e s i m u l a t i o n f o r oxygen p r e d i c t i o n and c o n t r o l ; 2) d e t e r m i n i n g the s t a b i l i t y and t u r g o r c r i t e r i a d u r i n g the s m o l t i f i c a t i o n p r o c e s s when s a l i n i t i e s i n and out o f the FVR are more s i m i l a r ; 3) q u a n t i f y i n g and comparing the e l a s t i c l i m i t s o f the l i n e r and o u t l e t s c r e e n t o the h y d r a u l i c f o r c e s b e i n g a p p l i e d by the i n f l u e n t flow; 4) i n v e s t i g a t i n g a l t e r n a t i v e s t o water supply systems i . e . PVC p i p e s i z e s , pumping c o n f i g u r a t i o n s e t c . 5) a p p l y i n g the CGSS t o oth e r salmonid s p e c i e s t o determine the economic f e a s i b i l i t y w i t h i n the FVR; 80 6) a p p l y i n g an o p t i m i z a t i o n f u n c t i o n t h a t r e l a t e s the t e c h n i c a l and economic as p e c t s o f t h i s s i m u l a t i o n ; 7) a survey from the commercial h a t c h e r i e s o f the break-down of the smolt p r o d u c t i o n c o s t s t h a t can then used t o augment and r e v i s e t h i s s i m u l a t i o n t o r e f l e c t h a t c h e r y c o s t s more a c c u r a t e l y . 8) the a d d i t i o n o f a more r e s o l u t e cash flow a n a l y s i s t o study q u a r t e r l y p e r i o d s . 9) the a d d i t i o n o f an investment a n a l y s i s r o u t i n e . 81 BIBLIOGRAPHY A l l e n , P.G., B o t s f o r d , L.W., Schuur, A.M. and Johnston, W.E., 1984. Bioeconomics o f Aquaculture. E l s e v i e r S c i e n c e P u b l i s h e r s , New York, NY. Beveridge, M., 1987. Cage Aquaculture. F i s h i n g News. Farnham. B j o r n d a l , T., 1988. The Norwegian A q u a c u l t u r e I n d u s t r y : I n d u s t r i a l S t r u c t u r e and Cost of P r o d u c t i o n . Marine P o l i c y , 12:122-142. B j o r n d a l , T., 1990. The Economics of Salmon A q u a c u l t u r e . B l a c k w e l l S c i e n t i f i c P u b l i c a t i o n s . London. Blackburn, D., 1989. A t l a n t i c Salmon-The S p e c i e s of Choice? A paper presented a t the 5th Annual Sunshine Coast A q u a c u l t u r e Conference. Sept. 5, 1989. S e c h e l t , B r i t i s h Columbia. B r e t t , J.R., 1979. Environmental F a c t o r s and Growth. I n : W.S. Hoar and D.J. R a n d a l l ( E d i t o r s ) , F i s h P h y s i o l o g y V o l . V I I I . Academic Press, New York, NY. B r e t t , J.R., C l a r k e , W.C. and Shelbourne, J.E., 1982. Experiments on Thermal Requirements f o r Growth and Food Conversion E f f i c i e n c y o f J u v e n i l e Chinook Salmon Oncorhynchus tshawytscha. Canadian T e c h n i c a l Report of F i s h e r i e s and A q u a t i c S c i e n c e s No. 1127. C l a r k e , C., 1982. E v a l u a t i o n o f the Seawater Challenge T e s t as an Index of Marine S u r v i v a l . A q uaculture, 28:177-183. C l a r k e , C. and Blackburn, J . , 1978. Seawater Challenge T e s t Performed on Hatchery Stocks o f Chinook and Coho Salmon i n 1977. F i s h e r i e s and Marine S e r v i c e s T e c h n i c a l Report, 761:1-19. Combs, S., 1986. B r i t i s h Columbia M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s . Cash Flow Model f o r Salmon Farming. Cook, M. and Canton, S., 1988. C a l c u l a t i o n o f Percent Gas S a t u r a t i o n i n Water by Use of a Spreadsheet. The P r o g r e s s i v e F i s h C u l t u r i s t , 50:248-250. Duston, J . and Saunders, R.L., 1989. The Entrainment Role of Photoperiod on Hypoosmoregulatory and Growth-Related Aspects of Smolting i n A t l a n t i c Salmon (Salmo s a l a r ) . Canadian J o u r n a l o f Zoology, 68:707-715. Egan, B.D., Egan, H. M. and Wright, B.F., 1989. F i n a n c i a l A n a l y s i s o f Salmon Farming i n C o a s t a l B r i t i s h Columbia: 82 A Computer-Based Model Approach. Department of F i s h e r i e s and Oceans, Economic and Commercial A n a l y s i s D i v i s i o n Report No. 54. Egan, D. and Kenny, E., 1990. Salmon Farming i n B r i t i s h Columbia - An Indus t r y i n T r a n s i t i o n . World Aquaculture, 21(1):6. F r a n t s i , C. and Justason, B., 1988. D i f f e r e n t S t r a t e g i e s f o r the T r a n s f e r o f A t l a n t i c Salmon Smolts t o Sea Water. B u l l e t i n o f the Aquaculture A s s o c i a t i o n o f Canada No. 3, 36-44. F r i d l e y , R.B., 1986. M o d e l l i n g , I d e n t i f i c a t i o n and C o n t r o l o f Aqua c u l t u r e Processes and F a c i l i t i e s , i n Automation and Data P r o c e s s i n g i n Aquaculture. IFAC, Trodheim, Norway. From, J . and Rasmussen, G., 1986. A Model o f F i s h Growth i n Aqua c u l t u r e . In: Automation and Data P r o c e s s i n g i n Aqua c u l t u r e . IFAC, Trodheim, Norway. Fromberg, D., 1991. Owner/Operator Cedar Brook Sea Farms. Personnal communications. Gates, J.M., MacDonald, C. and P o l l a r d , B., 1980. Salmon C u l t u r e i n Water Reuse Systems: An Economic A n a l y s i s . U n i v e r s i t y o f Rhode I s l a n d Marine T e c h n i c a l Report 78. Heard, W. and M a r t i n , R., 1979. F l o a t i n g H o r i z o n t a l and V e r t i c a l Raceways Used i n Freshwater and E s t u a r i n e C u l t u r e o f J u v e n i l e Salmon, Oncorhynchus spp.. Marine F i s h e r i e s Review, 41:18-23. Heard, W. and S a l t e r , F., 1978. Simple V e n t u r i Device f o r Mi x i n g Freshwater and Seawater i n an E s t u a r i n e C u l t u r e System. P r o g r e s s i v e F i s h C u l t u r a l i s t , 40:101-103. Hoar, W.S., 1989. The P h y s i o l o g y o f Smolting Salmonids. In: W.S. Hoar and D.J. R a n d a l l ( E d i t o r s ) , F i s h P h y s i o l o g y V o l . 11B. Academic Press, New York, NY. Iwama, G.K. and Tautz, A.F., 1981. A Simple Growth Model f o r Salmonids i n H a t c h e r i e s . Canadian J o u r n a l o f F i s h e r i e s and A q u a t i c S c i e n c e s , 38:649-656. Iwama, G.K. and F i d l e r , L.E., 1989. The U n i v e r s i t y i f B r i t i s h Columbia Aquaculture P r o d u c t i o n A n a l y s i s Computer Program, User's Manual. B.C. M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s . 83 K a b i r , M. and R i d l e r , N.B., 1984. The Demand f o r A t l a n t i c Salmon i n Canada. Canadian J o u r n a l o f A g r i c u l t u r a l Economics, 32:562-568. Kepenyes, J . , 1984. R e c i r c u l a t i n g Systems and Re-use of Water i n A q u a c u l t u r e . In: I n l a n d A quaculture E n g i n e e r i n g . Food and A g r i c u l t u r e O r g a n i z a t i o n o f U n i t e d Nations, Rome. Kenny, A., 1991. B r i t i s h Columbia Salmon Farmer's A s s o c i a t i o n . Personnal Communication, May 23, 1991. L a i r d , L.M. and Needham, T., 1988. Salmon and T r o u t Farming. John Wiley and Sons. Lee, B.T., 1988. Costs and Returns of Salmon Farming i n B.C. M.Sc. T h e s i s , U n i v e r s i t y of B r i t i s h Columbia. Leung, P.S. and Rowland, L.W., 1989. F i n a n c i a l A n a l y s i s of Shrimp P r o d u c t i o n : An E l e c t r o n i c Spreadsheet Model. Computers and E l e c t r o n i c s i n A g r i c u l t u r e , 3:287-304. L i a o , P., 1971. Water Requirements f o r Salmonids. The P r o g r e s s i v e F i s h C u l t u r i s t s , 33:210-215. MacGregor, R.J., 1986. B r i t i s h Columbia M i n i s t r y of A g r i c u l t u r e and F i s h e r i e s . Cash Flow Model f o r Salmon Farming. MacKinley, D., 1984. The P r e l i m i n a r y Design of an Aquaculture F a c i l i t y U s i n g Systems A n a l y s i s Techniques: A B r i t i s h Columbia Case Study. M.Sc. T h e s i s , U n i v e r s i t y of B r i t i s h Columbia. Malamus, S., 1991. Owner/Operator f o r P a c i f i c A quaculture L i m i t e d . Personnal Communications, March 11, 1991. M a r t i n , R. and Heard, W., 1987. F l o a t i n g V e r t i c a l Raceway t o C u l t u r e Salmon (Oncorhynchus spp.)• A q u a c u l t u r e , 61:295-302. M a r t i n , R. and Wertheimer, A., 1987. S u r v i v a l of Coho Salmon (Oncorhynchus k i t s u t c h ) C u l t u r e d i n Fresh Water and i n E s t u a r i n e Net Pens. Aquaculture, 61:181-191. M a r t i n , R. and Wertheimer, A., 1989. A d u l t P r o d u c t i o n of Salmon Reared a t D i f f e r e n t D e n s i t i e s and Released as Two Smolt S i z e s . The P r o g r e s s i v e F i s h - C u l t u r a l i s t , 51:194-200. McLean, W.E., 1980. Rearing Model f o r Salmonids. M.Sc. T h e s i s , U n i v e r s i t y o f B r i t i s h Columbia. 84 Meade, T.L., 1975. The Technology of C l o s e d System C u l t u r e of Salmonids. U n i v e r s i t y of Rhode I s l a n d Marine T e c h n i c a l Report No. 30. M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1989. E s t i m a t e d Costs and Returns f o r Chinook Salmon P r o d u c t i o n i n the Campbell R i v e r Area. Aquaculture and Commercial F i s h e r i e s Branch. M i n i s t r y o f A g r i c u l t u r e and F i s h e r i e s , 1991. Input Cost Survey f o r the Mainland A g r i c u l t u r a l R e p o r t i n g Region. P u b l i c A f f a i r s Branch, S t a t i s t i c a l S e r v i c e s U n i t . Moore-Clarke Company Incorporated, 1991. The Feed P l u s Concept. An i n d u s t r y brochure f o r salmon f e e d i n g . Vancouver, B.C. Myers, J . J . , Holm, C. and M c A l l i s t e r , R.F., ( e d i t o r s ) , 1969. Handbook of Ocean and Underwater E n g i n e e r i n g . McGraw-H i l l Book Company. New York, NY. Needham, T. 1990. Canadian A q u a c u l t u r e - L e t 1 s Farm the Oceans. World Aquaculture, 21(2):76-80. P e n n e l l , W., 1988. The B.C. Salmon Farming I n d u s t r y . B u l l e t i n o f the Aquaculture A s s o c i a t i o n of Canada No. 1, 5-20. Pond, S. and P i c k a r d , G., 1989. I n t r o d u c t o r y Dynamical Oceanography. Pergamon Press. New York. R i c k e r , W.E., 1979. Growth Rates and Models. In: W.S. Hoar and D.J. R a n d a l l ( E d i t o r s ) , F i s h P h y s i o l o g y V o l . V I I I . Academic Press, New York, NY. R i d l e r , N.B. and K a b i r , M., 1988. Economic Aspects o f Salmon Aqu a c u l t u r e i n A t l a n t i c Canada. Canadian I n d u s t r y Report o f F i s h e r i e s and A q u a t i c S c i e n c e No. 188. Saunders, R.L., 1991. Salmonid Researcher. B i o l o g i c a l S c i e n c e s Branch, Department of F i s h e r i e s and Oceans, B i o l o g i c a l S t a t i o n , S t . Andrews, N.B. Personnal Communications, A p r i l 26, 1991. Saunders, R.L. and Harmon, P.R., 1990. I n f l u e n c e of Photoperiod on Growth of J u v e n i l e A t l a n t i c Salmon and Development of S a l i n i t y T o l e r a n c e d u r i n g W i n t e r - S p r i n g . T r a n s a c t i o n s o f the American F i s h e r i e s S o c i e t y , 119:689-697. 85 Saunders, R.L., Henderson, E.B. and Harmon, P.R., 1985a. E f f e c t s o f Photoperiod on J u v e n i l e Growth and Smolting of A t l a n t i c Salmon and Subsequent S u r v i v a l and Growth i n Sea Cages. Aquaculture, 45:55-66. S c h u e l l e r , J . and Kr u t z , G., 1989. An Economic Model o f Corn Combine Forward Speed C o n t r o l . Computers and E l e c t r o n i c s i n A g r i c u l t u r e , 3:209-223. Spence, J . , 1989. The B.C. Salmon Farming I n d u s t r y , I t ' s S t a t u s and D i r e c t i o n . A paper p r e s e n t e d a t : The 5th Annual Sunshine Coast Aquaculture Conference. Sept. 5, 1989, S e c h e l t B r i t i s h Columbia. S t a u f f e r , G.D., 1973. A Growth Model f o r Salmonids Reared i n Hatchery Environments. Ph.D. T h e s i s . U n i v e r s i t y of Washington, S e a t t l e , Washington. Storebakken, T. and Austreng, E., 1987. R a t i o n L e v e l f o r Salmonids I . Growth, S u r v i v a l , Body Composition and Feed Conversion i n A t l a n t i c Salmon F r y and F i n g e r l i n g s . A q u aculture, 60:189-206. S u t t e r l i n , A.M., Henderson, E.B., M e r r i l l , S., Saunders, R.L. and Mackay, A.A., 1981. Salmonid r e a r i n g T r i a l s a t Deer I s l a n d , New Brunswick, With Some P r o j e c t i o n s o f Economic V i a b i l i t y . Canadian T e c h n i c a l Report o f F i s h e r i e s and A q u a t i c S c i e n c e s No. 1011. Tchobanoglous, G., 1979. Wastewater E n g i n e e r i n g : Treatment, D i s p o s a l , Reuse. McGraw-Hill Book Company, New York, NY. Thomsen, R., 1991. Software D i r e c t o r , I s l a n d S c i e n c e , Oregon. Personnal Communications, A p r i l , 26, 1991. Thomson, R., 1981. Oceanography of the B r i t i s h Columbia Coast. Canadian S p e c i a l P u b l i c a t i o n s o f F i s h e r i e s and A q u a t i c S c i e n c e s . Department of F i s h e r i e s and Oceans. Vennard, J . and S t r e e t , R., 1982. Elementary F l u i d Mechanics. John Wiley and Sons, New York, NY. Weber, W., 1970. Physicochemical Processes f o r Water Q u a l i t y C o n t r o l . W i l e y - I n t e r s c i e n c e , New York, NY. Wheaton, F.W., 1985. A q u a c u l t u r a l E n g i n e e r i n g . Robert E. K r i e g e r P u b l i s h i n g Company Inc., F l o r i d a . 

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:
https://iiif.library.ubc.ca/presentation/dsp.831.1-0058866/manifest

Comment

Related Items