Hundred-year decline of North Atlantic predatory ®shes Villy Christensen, Sylvie Gue¨ nette, Johanna J Heymans, Carl J Walters, Reginald Watson, Dirk Zeller & Daniel Pauly FisheriesCentre,UniversityofBritishColumbia,2204MainMall,Vancouver,BC,CanadaV6T1Z4 Keywords biomassdecline,ecosystemmodelling,NorthAtlantic,predatory¢sh FISHandFISHERIES,2003, 4, 1^24 # 2003 Blackwell Publishing Ltd 1 Abstract We estimate the biomass of high-trophic level ¢shes in the North Atlantic at a spatial scaleof0.58 latitudeby0.58 longitudebasedon23spatializedecosystemmodels,each constructedtorepresentagivenyearorshortperiodfrom1880to1998.Weextractover 7800datapointsthatdescribetheabundanceofhigh-trophiclevel¢shesasafunction ofyear,primaryproduction,depth,temperature,latitude,icecoverandcatchcomposi- tion.We then use a multiple linear regression to predict the spatial abundance for all North Atlantic spatial cells for1900 and for each year from1950 to1999. The results indicatethatthebiomassofhigh-trophiclevel¢sheshasdeclinedbytwo-thirdsduring the last 50-year period, and with a factor of nine over the century. Catches of high- trophiclevel¢shesincreasedfrom2.4to4.7milliontonnesannuallyinthelate1960s, and subsequently declined to below 2 million tonnes annually in the late1990s.The ¢shingintensityforhigh-trophiclevel¢shestripledduringthe¢rsthalfofthetimeper- iod and remained high during the last half of the time period. Comparing the ¢shing intensitytosimilarmeasuresfrom35assessmentsofhigh-trophiclevel¢shpopulations fromtheNorthAtlantic,weconcludethatthetrendsinthetwodataseriesaresimilar. Our results raise serious concern for the future of the North Atlantic as a diverse, healthyecosystem;wemaysoonbeleftwithonlylow-trophiclevelspeciesinthesea. Correspondence: VillyChristensen, FisheriesCentre, Universityof British Columbia,2204 MainMall, Vancouver,BC, CanadaV6T1Z4 Tel.:  1604 8225751 Fax:  1604 822 8934 E-mail: v.christensen@ ¢sheries.ubc.ca Received17Apr2002 Accepted30Aug2002 Introduction 2 Methodology 3 EcosystemmodelsfromtheNorthAtlantic 3 Assigningmodelstostrata 7 Fisheriescatches 8 Regression analysis 9 E¡ectofindividualmodelsontheregressionanalyses 11 E¡ectofcatchcompositionontheregressionanalyses 13 Predicting biomass of predatory ®shes 13 Catches 14 Fishingmortalities 16 Discussion 17 Acknowledgements 21 References 21 Christensen, V., S. Guénette, J. J. Heymans, C.J. Walters, R. Watson, D. Zeller and D. Pauly. 2003. Hundred year decline of North Atlanticpredatory fishes. Fish and Fisheries 4(1): 1-24.