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Sea Around Us project newsletter, issue 39, January/February 2007 Forrest, Robyn; Sea Around Us Project Jan 31, 2007

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SSSS Seeee e aaaa a     AAAA Arrrr r ouououou ounnnn ndddd d     UUUU Ussss sThe Sea Around Us Project NewsletterIssue 39 – January/February 2007Lessons from areconstruction of catchtime series for Mauritaniaby Didier GascuelFor a fisheries scientist,Mauritania is probablyone of the world’smost fascinating countries.It is a very poor country, adesert for the bulk of itsterritory.  Landing for the fisttime at the airport ofNouakchott, the capital, is ashock: how can people livehere, in the middle ofnowhere?But in fact, this is a countryof very enterprising people,and there are naturalresources: large irondeposits in the desert,recently discovered oilfieldson the shelf, an intensiveupwelling along the coast,and a large, extremelyproductive shallow, the‘Banc d’Arguin.’ As a result,Mauritania’s coastal watersare (or have been) amongthe world’s richest fishinggrounds, and the fisherysector is of hugeimportance to the country’seconomy. In 2005, officiallandings were estimated ataround 720,000 tons,representing 6 % of GrossDomestic Product,generating 30 % of thevalue of Mauritanian exportsand 30 % of the state’srevenue (IMROP 2007).The fisheries statisticsavailable from Mauritania, atleast those submitted toFAO, leave much to bedesired, however.  While afisheries monitoring system,based on logbooks,sampling at landinglocations, and onboardobservers has beendeveloped by theMauritanian nationalfisheries institute (IMROP) inthe 1980s, itsimplementation has faceddifficulties, and a completedatabase is available onlysince 1991 for the industrial,and 1997 for the small scalefisheries. Only scattered andheterogeneous statisticswere published earlier,covering short periods.I have attempted toharmonize these differentdatasets, and to generate, inthe process, a ‘catchreconstruction’ (sensu Zelleret al. 2006) of the industrialpelagic and demersalfisheries, and of the artisanalfisheries, covering the years1950 to 2005 (Gascuel etal., in prep.).Seven lessons emergefrom this reconstruction1. Even if estimates remainuncertain, notably for the1950s and 1960s, the catchreconstruction is extremelyuseful in that it provides afirst picture of long termcatch trends by the variousfisheries which haveexploited (what became) theMauritanian EEZ.  The FAOstatistics are really deficientin this regard. The mainreason for this is that the bulkof the catch is due to foreignfleets, and thus is notreported by Mauritania toFAO. Of course, the foreignboats have to declare theircatches. Their declarations,however, refer to larger FAOfishing areas, not theMauritanian EEZ. Thus, in FAOstatistic, neither the catch bycountry, nor the catch by areagives information on thecatch taken from theMauritanian EEZ.2. The results I obtained canbe compared with the catchestimates by the Sea AroundUs project database (seewww.seaaroundus.org). Thelatter relied on Watson et al.(2004), who allocated theFAO catch by (groups of)species to ½ degree cells,and regrouped these intodifferent EEZs. This case studyof Mauritania was the firstCont. on page 2 - MauritaniaPage 2Sea Around Us – January/February 2007The Sea Around Us project newsletter ispublished by the  FisheriesCentre at the Univer-sity of British Co-lumbia. Includedwith the FisheriesCentre’s newsletterFishBytes,six is-sues of this news-letter are publishedannually. Subscrip-tions are free of charge.Our mailing address is: UBC Fisheries Cen-tre, Aquatic Ecosystems Research Laboratory,2202 Main Mall, Vancouver, British Colum-bia, Canada, V6T 1Z4. Our fax number is(604) 822-8934, and our email address isSeaNotes@fisheries.ubc.ca. All queries (in-cluding reprint requests), subscription re-quests, and address changes should be ad-dressed to Robyn Forrest, Sea Around UsNewsletter Editor.The Sea Around Us website may be foundat www.seaaroundus.org and contains up-to-date information on the project.The Sea Around Us project is a Fisheries Centre partner-ship with the Pew Charitable Trusts of Philadelphia,USA. The Trusts support nonprofit activities in the areasof culture, education, the environment, health and human serv-ices, public policy and religion. Based in Philadelphia, theTrusts make strategic investments to help organisations andcitizens develop practical solutions to difficult problems. In2000, with approximately $4.8 billion in assets, the Trustscommitted over $235 million to 302 nonprofit organisations. ISSN 1713-5214   Sea Around Us (ONLINE)independent test of the resultsobtained by Watson et al. (2004),and it passed the test with flyingcolours: total catches in theMauritanian EEZ from the SeaAround Us are very close to myestimates of the official landingsof the industrial fisheries (whichshould roughly resemble theFAO data). On the other hand, adetailed look allowsidentification of the limitationsof the method of Watson et al.(2004), which requires localknowledge for validation. Thus, Ifound that demersal catches offMauritania were overestimatedin the Sea Around Us database,while pelagic catches wereunderestimated. The mainreason is the fact that thefisheries history differs betweenMauritania and its neighbours,particularly Senegal. Mauritaniahas no tradition of fishing, and itsresources have been exploitedby mainly foreign countriestargeting the small pelagicfishes. On the other hand, smallscale fisheries targetingdemersal resources developedvery early in Senegal. Thus, thedemersal and pelagic catches tobe allocated between these twocountries do not simply dependon their fishable areas. Themethod, however, allows for theincorporation of informationsuch as provided here, and thusit should be possible to correctthe result in a subsequent catchallocation.3. Several hundred thousandtons of small pelagic fishes,recorded in the IMROP databaseduring the 1980s and 1990shave simply disappeared fromthe statistics reported to FAO.These had been caught byforeign boats (particularly fromEastern Europe), operating onthe basis of special agreementsas ‘Mauritanian chartered boats.’Thus, they probably should havebeen declared as Mauritaniancatches. But they were not, andneither do they appear (or onlypartially) in the landingsreported by the foreigncountries in question.4. As in many other developingcountries, official landings arealso underestimated due to alarge amount of undeclared by-catches and neglect of the smallscale fisheries. Indeed, the latterhave always been consideredinsignificant in Mauritania. Thiswas more or less true before theearly 1990s, when a fewhundreds ‘pirogues’ wereinvolved, with annual catchesunder 15,000 t. However, sincethen, their number has increasednearly ten-fold, generatingcatches of around 80,000 t, ofwhich 60,000 t are demersal fishand invertebrates. Obviously, a‘small-scale’ fishery of suchmagnitude is a major economicfactor, whose impacts on theecosystem can no longer beignored. As for the by-catch, ithas been so far ignored becausethe vessels reportoverwhelmingly the speciesthey target, and for which theyhave a license. As if shrimptrawlers caught only shrimps,and the cephalopod fishery onlyoctopus! Taking into account theundeclared by-catches leads toan increase of the industrialdemersal catches by a factor ofover 1.7.5. As a consequence, the overallpicture of Mauritanian fisheries isstrongly modified. So far, it wasthought that the industrialfishery for small pelagicsoverwhelmingly dominated thefisheries sector. While this is stilltrue in term of tonnage (indeedMauritania has one of the worldlargest reduction fisheries,where the catch is used formaking fishmeal), this may notbe true in term of value or valueadded, as the demersal fisheriesMauritania - Continued from page 1Continued on page 3 - MauritaniaAs aconsequence,the overallpicture ofMauritanianfisheries isstronglymodifiedPage 3 Sea Around Us – January/February 2007(industrial and small-scale),catching higher-priced speciessuch as hake, octopus, shrimp,etc., have much higher catchthan previously thought.6. Having established thatdemersal resources areimportant, we must then dealwith the fact that theseresources suffer fromtremendous overexploitation.The industrial demersal fisheriesdeveloped in the late 1960s,mainly targeting octopus, whoseabundance increased at thattime, probably due to theprevious overexploitation ofbottom fish, notably porgies(family Sparidae). Since then,total demersal catches haveremained around 180,000 t,albeit with a huge increase offishing effort. For instance, thenumber of industrial trawlersgrew from around 150 in theearly 1980s to 300-350 in thelate 1990s/early 2000s. Ofcourse, their fishing efficiencyhas also increased, which furtherincreased effective effort. In theprocess, various species groupshave been successivelyexploited, then overexploited.This was probably the case forseveral fishes belonging to theSparidae community in the1960s and 1970s. Octopus hasbeen overexploited since themid 1980s, which induced adecrease in cephalopod landingsfrom a maximum of 55,000 topresently about 35,000 t.Catches of coastal Scianidaereached their maximum in the1990s and are now decreasingtoo. Now, it is turn of the mulletand shrimps. Overall, thedemersal biomass has beenstrongly depleted: at present, it isabout 25 % of what it was in1982, when regular trawlsurveys began (Gascuel et al.,submitted). This corresponds tothe loss of 20,000 t per year.Moreover, the biomass of toppredators has been reduced by afactor of 8 to 10 and up to 20 forthe most affected species. Themean trophic level of the catch,and its biodiversity decreased,inducing a higher sensitivity toclimatic variability.7. Mauritania is, finally, a veryclear case study of aninequitable allocation offisheries resources. Almost allthe large fishing countries of theworld have exploitedMauritanian waters. Octopus anddemersal fishes have beentargeted by Japanese, then bySpanish, Korean and Chinesevessels. Pelagic fishes haveattracted vessels from Russia,Ukraine and other easternEuropean countries and, morerecently, Dutch vessels. TheMauritanian industrial fisheriesremained limited in spite ofseveral attempts to developnational or joint ventures,especially during the 1980s. Ofcourse, foreign countries have topay for licenses or fishingagreements. Presently, 30 % ofpublic receipts come from theEU – probably not a good basisfor exerting national sovereignty.But the main part of the catcheswas and is still not landed inMauritania. Rather, the foreignvessels offload in the CanaryIslands (i.e., in Spain), or directlyin their country of origin.Mauritania benefits neitherthrough jobs, nor value added.As for the small-scale fishery, wesaw that it was very limited for along time, and that it hasdeveloped only since the mid1990s, partially in competitionwith industrial fisheries – andMauritania - Continued from page 20200,000400,000600,000800,0001,000,0001950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005Industrial pelagicUndeclared by-catchesIndustrial demersalSmall scale fisheryTonnes0200,000400,000600,000800,0001,000,0001950 1955 1960 1965 1970 1975 1980 1985 1990 1995 2000 2005Official landings of theindustrial fisheriesSAUP previousestimatesTonnesFigure 1 – Reconstruction of the catch time series off Mauritania.Top: desegregation by fisheries. Bottom: comparison with SAUP previous estimatesContinued on page 4 - MauritaniaMauritaniais a veryclear casestudy ofaninequitableallocationoffisheriesresourcesPage 4Sea Around Us – January/February 2007Publications Mail Agreement No: 41104508Selected recent publicationsAlder, J., and D. Pauly. (Editors) 2006. On the multiple Uses of Forage Fish: from Ecosystem toMarkets. Fisheries Centre Research Reports 14(3), 109 pp.Berman, M. and Sumaila, U.R. 2006. Discounting, amenity values and marine ecosystem restoration.Marine Resource Economics 21(2), 211-219.Chuengpagdee, R., D. Preikshot, L. Ligouri and D. Pauly. 2006. A public sentiment index forecosystem management. Ecosystems 9, 463-473.Kaschner, K., R. Watson, A.W. Trites and D. Pauly. 2006. Mapping world-wide distribution of marinemammal species using a Relative Environmental Suitability (RES) model. Marine EcologyProgress Series. 316, 285-310.Morato, T., R. Watson, T.J. Pitcher and D. Pauly. 2006. Fishing down the deep. Fish and Fisheries 7(1),24-34.Palomares, M.L., E. Mohammed and D. Pauly. 2006. European expeditions as a source of historicabundance data on marine organisms. Environmental History. 11 (October), 835-847.Palomares, M.L.D., K.I. Stergiou and D. Pauly. (Editors) 2006. Fishes in Databases and Ecosystems.Fisheries Centre Research Reports 14(4), 95 pp.Pauly, D. 2006. Major trends in small-scale marine fisheries, with emphasis on developing countries,and some implications for the social sciences. Maritime Studies (MAST) 4(2), 7-22.Sumaila, U.R. and D. Pauly (Editors) 2006. Catching more bait: a bottom-up re-estimation of globalfisheries subsidies. Fisheries Centre Research Reports 14(6), 114 pp.Sumaila, U.R., J. Alder, and H. Keith. 2006. Global scope and economics of illegal fishing. MarinePolicy 30, 696-703.Watson, R., C. Revenga and Y. Kura. 2006. Fishing gear associated with global marine catches: IDatabase development. Fisheries Research 79, 97-102.Watson, R., C. Revenga and Y. Kura. 2006. Fishing gear associated with global marine catches: IITrends in trawling and dredging. Fisheries Research 79, 103-111.Zeller, D., S. Booth and D. Pauly. 2006. Fisheries contributions to GDP: Underestimating small-scalefisheries in the Pacific. Marine Resource Economics  21(4), 367-386.Zeller, D., S. Booth, P. Craig, and D. Pauly. 2006. Reconstruction of coral reef fisheries catches inAmerican Samoa, 1950 – 2002. Coral Reefs 25, 144-152.For more Sea Around Us publications, click on the Publications link at www.seaaroundus.org.only after the resources weremuch reduced.ConclusionThe context in whichMauritanian fisheries scientistsoperate, and try to assess stocksand fisheries is thus verychallenging. Perhaps the veryrecent development of an oilindustry will make it possible forMauritania to acquire moreweight in internationalnegotiations and to manage itsfisheries resources, and theaccess of foreign fishing fleet toits waters in a more equitablefashion, i.e.,  so that more of thebenefits accrue to Mauritania.There is no doubt thatinternational scientificcooperation will remain useful inthis process.ReferencesIMROP, 2007. Rapport de synthèsedu 6ème Groupe de Travail surl’évaluation des ressources etl’aménagement des pêcheriesde la ZEE mauritanienne.Document Imrop, 26p.Gascuel, D., et al. in prep. Thereconstruction of catches dataseries in the Mauritanian EEZ(1950/2005). Fisheries CentreResearch Reports.Gascuel, D., et al. submitted. Thedecline of demersal resourcesin North-West Africa: ananalysis of Mauritanian trawlsurvey data over the last 25years. Submitted to AfricanJournal of Marine Science.Watson, R., et al. 2004. Mappingglobal fisheries: sharpeningour focus. Fish and Fisheries 5:168-177.Zeller, D., et al. 2006. Reconstructionof coral reef fisheries catches inAmerican Samoa, 1950 – 2002.Coral Reefs 25: 144-152.AcknowledgementsThis study was done with thesupport of a Marie Curiefellowship, within the sixth EUFramework programme. I alsothank the Sea Around Us projectfor hosting me during mysabbatical at the FisheriesCentre.Mauritania - Continued from page 3The contextin whichMauritanianfisheriesscientistsoperate, andtry to assessstocks andfisheries isthus verychallenging


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