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Sea Around UsThe Sea Around Us Project NewsletterIssue 4 – May/June 2000On Sunday, April 30,2000, those fromthe FisheriesCentre who are involved inthe Sea Around Us Project(SAUP) gathered atDunsmuir Lodge, nearVancouver Island’s SwartzBay, for the welcomedinner (the first of thelegendarily divine meals atDunsmuir) to the SAUPMethodology Workshop.They were joined by sixreviewers whom theyinvited as external auditorsto give insights andvalidity to their work.The workshop proper,which lasted from Monday,May 1 to Friday, May 5,allowed those involved inthe SAUP to get an idea ofhow their own project fitinto the larger scheme ofthings, as well as getfeedback from those whohave not worked on theprojects on an intimatelevel.  The visitors eachbrought a differentperspective to theproceedings. Lee Alverson(President, NaturalResources Consultants Inc.,and Professor of Fisheries ,University of Washington)brought with him hisextensive experience withfisheries management.Paul Fanning (Fisheries andOceans Canada, Halifax)and Poul Degnbol(Director, Institute forFisheries Management andCoastal CommunityDevelopment, Denmark)had perspectives from thetwo sides of the Atlantic.Kevern Cochrane andRichard Grainger (both ofthe UN Food andAgriculture Organisation inRome) had insights intointernational standards,and Jay Maclean (freelancewriter and editor) kept thefocus on the project’sobjective. With the addedsupply of contact names,advice, and suggestionsfrom the visitors, theSAUP’s already impressivearsenal was improved.Because timeconstraints and lackof personnel werethe recurring concernsabout the project, somerearrangement of prioritiesof the SAUP was necessary.Two projects were movedfrom the SAUP to bepicked up later as FisheriesCentre projects.  Dataanalysis would be done onvarying levels, wheredetailed models will come
		
out of locations in theNorth Atlantic where datais rich, whereas moregeneral and robust modelsthat could be appliedworldwide will come outof locations where data ispoor. These, along withother useful suggestions,came out of the visitors’insights.Although some of thereviewers were intiallyhesitant about the scopeand purpose of the SAUP,they were soon won over.The project was lauded forits holistic and broadapproach, its leadership,and its innovation.Concerns such as potentialgaps in data, targetaudience for the reports,and degree of depth, werealso addressed.There is less than ayear to go on theSAUP. As the clockticks, the participants willfeel the time crunch morekeenly. However, their taskswill be aided by the ideasand suggestions that cameout of this workshop.Amy Poon is an M.Sc. student atthe Fisheries Centre, and, alongwith Yvette Rizzo, acted asrapporteur at the SAUP workshop.			The Sea Around Us project newsletter ispublished by the  Fisheries Centre at the Uni-versity of British Colum-bia. Included withthe Fisheries Cen-tre’s newsletterFishBytes,six is-sues of this news-letter are pub-lished annually.Subscriptions arefree of charge.Our mailing address is: UBC Fisheries Cen-tre, 2204 Main Mall, Vancouver, British Co-lumbia, Canada, V6T 1Z4. Our fax number is(604) 822-8934, and our email address isSeaNotes@fisheries.com. All queries (includ-ing reprint requests), subscription requests,and address changes should be addressed toMelanie Power, Sea Around Us Newsletter Edi-tor.The Sea Around Us website may be foundat www.fisheries.ubc.ca/Projects/SAUP/index.htm, and contains up-to-date infor-mation on the project.This is a summary of: D. Zeller and D.Pauly (2000) How life history patternsand depth zone analysis can helpfisheries policy. In: Pauly, D. and Pitcher,TJ. (eds) Methods for assessing theimpact of fisheries on marineecosystems of the North Atlantic.Fisheries Centre Research Reports 8(1):(in prep).The stocks of anexploited fish speciesmay be utilized by morethan one fishery sector duringdifferent stages in the specieslife history. Often, scientists andmanagers alike view life historypatterns as a multi-dimensionalproblem, with complexinteractions betweencomponents defined byecology, time andoceanography. Often thiscomplexity has made it difficultto assimilate effects of multiplefishery sectors on a species andthe industry it supports. Thismay be either due to theperception of multi-dimensional complexitythought to be intractable, orbecause of an oversight ofbasic patterns.The life-history patterns of fishspecies are complex. But muchof this complexity can becaptured in simple diagrams ofcoastal transects, wherejuveniles usually occur inshorein large numbers, while adultsare often in deeper, offshorewaters. Here we argue that thismulti-dimensional complexitycan be reduced to a simpler,two-dimensional life historypattern, while still capturingthe essential information.  BothCharles Darwin and Alexandervon Humboldt used themethod of reduceddimensionality to focus onesattention to the key issueswhile capturing most of thesignificant informationconcerning the topic at hand.For example, after reviewingmuch literature, Darwinconcluded that “latitude is amore important element thanlongitude” for explaining thedistribution of organisms(Barrett et al. 1987).  It wasHumboldt, however, who firstused a transect technique tovisualize the advantage ofreduced dimensionality inexplaining observed patterns indistribution (Gayet p. 2284-2287 in Tort 1996).  In fisheriesscience, a classic example ofdata suitable for reduceddimensionality was presentedby Garstang (1909) for theNorth Sea plaice (Pleuronectesplatessa, Figure 1 - page 3).Heincke (1913) re-expressedthis as a ‘law’ wherein waterdepth and/or distance fromshore explained most of theobserved life historydistribution patterns.The life history characteristicsof many species and stocksshow generalized two-dimensional patterns, involvingwater depth and/or distancefrom shore. For example, FAO(1972) used this approach formany species in their Atlas ofthe Living Resources of theSeas. It is recognized that aninshore/offshore axis maybetter convey information onstructure and processes thanan alongshore axis or generalgeographic map view (Paulyand Lightfoot 1992).  A goodexample of this isdemonstrated by comparisonof Garstang’s map-view ofplaice size distribution in theNorth Sea (Figure 1) with ourrepresentation of the sameinformation for the same					
			Continued on page 4 - Life Histories	 		Figure 1: Schematic representation (geographic map view) of the distribution of plaice (Pleuronectes platessa) in the North Sea.Mean sizes (cm TL) are given for each depth isobar (modified after Garstang 1909) 0.11101001000100000.1 1 10 100 1000Distance (km)Depth (m)Larval stage Dispersal and settlement  Nursery/juvenile stage Ontogenetic movements  Adult stage Spawning migrations  Spawning  Figure 2: Generalised life history pattern by depth zone for plaice in the North Sea (Pleuronectes platessa). Depth transect from53.8ºN, 8.6ºE to 56.9ºN, 3.5ºE.			species and area (Figure 2 -page 3).  Such a transectapproach allows the use oficons for key processes, andpermits standardization of axis(e.g. log scale), which enablesmost species or stocks to bedirectly compared acrossextensive depth and distancescales. Application of thistransect method in the contextof the Sea Around Us Projectwill require drawings of similartransects for all importantcommercial species of theNorth Atlantic.The visualization of two-dimensional life historypatterns is clearly only a smallpart in our evaluation ofecosystem effects of fishing(see issue 3, Sea Around Usnewsletter). Firstly, we will usethese transect distributions tohelp assign catch data to areassuch as those described in theclassification systems of LargeMarine Ecosystems (Shermanand Duda 1999) and‘biogeochemical provinces’(Longhurst 1995). A consensussynthesis approach to theseclassification systems is beingconsidered by the Sea AroundUs Project (see Issue 2, Jan/Feb2000). Secondly, the depth anddistance from the coast ofmajor fish populationcomponents determines theirrelative vulnerability to coastal(often small-scale) and offshore(often large-scale) fishing gearand hence potentialinteractions and conflictsbetween these different fisherysectors. We will be super-imposing the various scales ofoperation of each fishery sectoronto the life history illustrationsof each species concerned.Thus, coastal transects of fishdistributions will show differentspecies ‘connect’, through theirlife history patterns, differentfisheries sectors, such as smallwith large scale fisheries.We consider the presentapproach useful forvisualizing theexistence, interaction andpotential conflicts betweendifferent fishery sectors forspecies or stocks whose lifehistory patterns illustrate theneed for improved integrationof management of the differentfishery sectors. This may applyin particular to rationalizationof overcapitalized fisheries. Theproposed visualization may beused by management toincorporate the concept of lifehistory interconnectivitybetween different fisherysectors and may assist in theformulation of more informedpolicy options for ecosystem-based management of NorthAtlantic fisheries.Acknowledgements:We would like to thank theEnvironment Project of ThePew Charitable Trusts for theirfunding of the Sea Around UsProject.  Thanks also to Drs TonyPitcher, Reg Watson and LoreRuttan for assistance with thedepth transects and forcomments on an earlier versionof this article.References:Barrett,PH; Gautrey,PJ;Herbert,S; Kohn,D and Smith,S(Editors). 1987. Charles Darwin’sNotebooks, 1836-1844:geology, transmutation ofspecies, metaphysical enquiries.British Museum (NaturalHistory), London and CornellUniversity Press, Ithaca andNew York, 747 p.FAO. 1972. Atlas of the livingresources of the seas. FAOFisheries Circular No. 126.Garstang, W. 1909. Thedistribution of the plaice in theNorth Sea, Skagerrak andKattegat, according to size, age,and frequency.  Rapp. Counc.Int. Explor. Mer. 1:136-138.Heincke, F. 1913. Investigationon the plaice. General Rapport I.Plaice fishery and protectiveregulation. Part I. Rapp. P.-v.Reun. Counc. Int. Explor. Mer.17A:1-153.Longhurst, AR. 1995. Seasonalcycles of pelagic productionand consumption. Prog.Oceanog. 36:77-167.Pauly,D and Lightfoot,C. 1992. Anew approach for analyzingand comparing coastalresource systems. NAGA15(2):7-10.Sherman,K. and Duda,AM. 1999.Large Marine Ecosystems: anemerging paradigm for fisherysustainability. Fisheries24(12):15-20.Tort, P. (Editor) 1996.Dictionnaire du Darwinisme etde l’ évolution. Volume 2.Presses Univeritaires de France.Dirk Zeller is a post-doctoral fellow withthe Sea Around Us project. Daniel Paulyis Project Leader.Life Histories - Continued from page 2