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Status and Trends in Global Marine Fisheries

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Status and Trends in Global Marine Fisheries Status and trends in global marine fisheries Trevor A. Branch School of Aquatic and Fishery Sciences University of Washington Climate Change and the Future of Food Bellingham, WA, 25 October 2012 All fisheries will be collapsed by 2048 Boris Worm Time magazine, November 2006 That’s just mind- bogglingly stupid Ray Hilborn Seattle Times, 2006 NCEAS working group: Finding common ground in marine conservation and management Worm et al. (2009) Science 325:578-585 Rebuilding global fisheries Catches Assessments ) Surveys Percent collapsed Percent Average length (cm length Average Year Year Worm et al. (2009) Science 325:578-585 Rebuilding global fisheries Rebuilding global fisheries Overfishing Fishery reduction RAM Legacy database ) MSY u (u/ Harvest rate rate Harvest RAM Myers, 1952-2007 Lightly Recovery exploited Biomass (B/BMSY) Worm et al. (2009) Science 325:578-585 Ricard et al. (in press) Fish and Fisheries. doi: 10.1111/j.1467-2979.2011.00435.x “we will be left with a Fishingdiet of jellyfishdown marine and planktonfood webs stew” (Christensen(Pauly & 1996, Watson Pauly 2003) et al. 1998) Picture: Sea Around Us Project, www.seaaroundus.org Christensen (1996) Rev Fish Biol Fish. 6:417-442 Pauly et al. (1998) Science 279:860-863 Pauly & Watson (2003) Scientific American July:43-47 Fishing food webs Scientific American March 24, 2009, by Dave Beck & Jennifer Jacquet Fishing food webs Food webs and trophic levels 4 3 level 2 Trophic Trophic 1 Slide courtesy of Tim Essington Fishing food webs Mean trophic level trophic Mean Pauly et al. (1998): “declined in recent decades at a rate of about 0.1 per decade” Year Pauly et al. (1998) Science 279:860-863 Fishing food webs 2010 data: increased in recent decades Mean trophic level trophic Mean Pauly et al. (1998): “declined in recent decades at a rate of about 0.1 per decade” Year Branch et al. (2010) Nature 468:431-435 Fishing food webs Trophic level Hypothesis: High fishing down Med. marine food webs Low 1950 2007 Catch amount Trophic level Data: High fishing increasing Med. at all levels of Low marine food webs 1950 2007 Catch amount Branch et al. (2010) Nature 468:431-435 Profits not predators Development of new fisheries continues… Cumulative Fisheriesdeveloped Year Sethi, Branch & Watson (2010) PNAS 107:12163-12167 Profits not predators But new fisheries are low volume Cumulative (million (million t) Annual catch catch Annual Year Sethi, Branch & Watson (2010) PNAS 107:12163-12167 Profits not predators And new fisheries are low value Cumulative Value Value (billion 2000) (billion US$ year Year Sethi, Branch & Watson (2010) PNAS 107:12163-12167 Trends in status Proxy based on catch Actual status from trends over time biomass Collapsed Collapsed Overexploited Overexploited Fully exploited Fully exploited Developing Developing Percentage of fisheries Percentage Year Branch et al. (2011) Conservation Biology 25:777-786 Trends in status Assessed stocks ) (RAM Legacy) unfished FAO status reports Region of maximum yield Biomass (% of (% Biomass Year Worm & Branch (2012) Trends Ecol Evol. doi: 10.1016/j.tree.2012.07.005 Trends in status ) gigawatt Catch (million t) (million Catch Effort ( Effort Year Worm & Branch (2012) Trends Ecol. Evol. doi: 10.1016/j.tree.2012.07.005 Effort data: Watson et al. (2012) Fish and Fisheries doi: 10.1111/j.1467-2979.2012.00483.x Trends in status 80% Food provision: globally catching 75-95% of maximum sustainable yield Branch et al. (2012) in prep. Trends in status 30% Over-harvesting 30% of large fisheries FAO (2012) The state of world fisheries and aquaculture 2012, FAO, Rome Trends in status 57% Sustainable catches from 57% of large fisheries FAO (2012) The state of world fisheries and aquaculture 2012, FAO, Rome Trends in status 13% Still developing 13% of large fisheries FAO (2012) The state of world fisheries and aquaculture 2012, FAO, Rome Trends in status 0.1% Could survey all coastal ecosystems by redirecting 0.1% of current subsidies From subsidy estimates in Sumaila et al. (2010) Journal of Bioeconomics 12:201-225 Acknowledgments • FAO: global catch data, status reports • Sea Around Us project: price data, catch data • RAM Legacy database: stock assessments • FishBase for trophic levels and other biological data • Funding: NCEAS, National Science Foundation • Coauthors on Worm et al. (2009), Branch et al. (2010, 2011), Sethi et al. (2010), also Tom Carruthers, Michael Wilberg and Sean Anderson • Special thanks to Boris Worm and Ray Hilborn and NCEAS group members Fishing food webs Top predators Rainer Froese Daniel Pauly FishBase trophic levels 2010 data Atlantic cod Mean trophic level trophic Mean Year Pauly & Froese (2012) Marine Policy 36:746-752 Fishing food webs Top predators Rainer Froese Daniel Pauly FishBase trophic levels 2010 data Atlantic cod 2011 data Atlantic cod Mean trophic level trophic Mean Year Branch (2012) Marine Policy 36:1191-1192 Trends in status Kleisner et al. (2012) method Actual status from applied to catches biomass Collapsed Collapsed Recovering Overexploited Overexploited Fully exploited Fully exploited Developing Percentage of fisheries Percentage Developing Year RAM Legacy assessments for stocks yielding 20-25% of global catches Trevor A. Branch, unpublished analysis of Kleisner et al. (2012) Fish and Fisheries doi: 10.1111/j.1467-2979.2012.00469.x Trends in status Froese et al. (2012) method: retrospective bias 1959 1969 1979 1989 1999 2009 Percentage of fisheries of Percentage Year Sean C. Anderson, unpublished analysis of Froese et al. (2012) Marine Biology 159:1283-1292 The future of fish RAM Legacy stock assessments (n=331) (20-25% of global catches) Ricard et al. (in press) Fish and Fisheries. doi: 10.1111/j.1467-2979.2011.00435.x The future of fish Compiled trawl surveys (n=29) (14 of 64 LMEs) Branch et al. (2010) Nature 468:431-435 The future of fish Proposal: global fleet of scientific survey vessels • Survey all LMEs every 5 years • Costs around US$7 million per year to run the R/V Dr Fridtjof Nansen, which surveys roughly 3 LMEs in a year • Surveying the unsurveyed LMEs every 5 yr would cost ~$23 million per yr • Who would be in charge? FAO? Norway? • Data access? Private for 2-5 years then publicly available Rough cost estimates courtesy of Åsmund Bjordal, Institute of Marine Research, Norway The future of fish $23 million in context • Pew Charitable Trusts: $250 million per yr • Global Environmental Facility: $500 million per yr, $18 million for MPAs in Brazil in 2011 • James Webb Telescope: $9 billion • Global subsidies: $25-29 billion in 2003 alone Branch et al. (2010) Nature 468:431-435 Trends in status Catch proxy: only scoring 25% for food provision from marine fisheries Halpern et al. (2012) Nature 488:615-620 .
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