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The Future of Fisheries: science, policy and societal challenges

The Future of Fisheries: science, policy and societal challenges. Andrew A. Rosenberg, University of New Hampshire.

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The Future of Fisheries: science, policy and societal challenges

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  1. The Future of Fisheries:science, policy and societal challenges Andrew A. Rosenberg, University of New Hampshire

  2. Predicting natural mortality rates and reproduction-mortality trade-offs from fish life history data. Myers, RA | Doyle, RWCanadian Journal of Fisheries and Aquatic Sciences. Vol. 40, no. 5, pp. 612-620. 1983. A method for estimating natural mortality and evolutionary constraint on fish life histories is presented based on the assumption that observed life histories are evolutionarily stable. I

  3. Rapid worldwide depletion of predatory fish communities 10 Atlantic Atlantic Atlantic 8 4 8 4 2 4 0 0 0 1960 1980 2000 1970 2000 1960 1980 2000 8 Indian Indian Indian 8 8 4 Catch per 100 hooks 4 4 0 0 0 1960 1980 2000 1960 1980 2000 1970 2000 8 8 Pacific Pacific 8 Pacific Myers and Worm (2003) 4 4 4 0 0 0 1960 1970 1980 1955 1965 1975 1955 1965 1975

  4. (t/km2) Biomass of table fish in 1900 ( Christensen et al. 2003)

  5. and in 2000….

  6. The History of Fishing Expansion to new areas, fishing methods and products resulting in massive overexploitation of marine ecosystems

  7. Biomass of cod on the Scotian Shelf in 1852 1,264,000 metric tons based on 19-century fishing logs carrying capacity, Myers et al 2001 • Average size cod in the 1990s, 6.5 lbs. Average size cod in the catch 1850s, 20 lbs. Relative cod size

  8. Localized Fishery Expansion Change in Relative Concentration of Fishing Effort 1935 1907 Analysis by S. Claesson, UNH

  9. Minimum Catch for Downeast Maine – 1861 223 vessels averaging 45 tons caught: 12,456 mt of cod Est. total Gulf of Maine Catch 1861 78,600 mt Total Gulf of Maine Cod Catch 1998 - 4156 mt 1999 - 1646 mt 2000 - 3730 mt 2007 - 3440 mt

  10. Cod Landings in the Gulf of Maine

  11. Mean Trophic Levels from Statistical Bulletin Landing Data (1901-1935) and LME Northeast US Continental Shelf Landings (1950-2003) Halibut = 4.59 Pollock = 3.75 Cusk = 4.22 Haddock = 3.58 Cod = 4.01 Herring = 3.46 TL: www.seaaroundus.org

  12. Evidence for ecosystem effects • Large declines in overall abundance of many stocks are have been documented • Fisheries can effect the structure and functioning of ecosystems at all levels • Regime shifts can be caused by physical forcing, fishing, or a combination of both. • Shifting baselines alter perceptions of marine ecosystems, masking the extent of ecosystem change. • Realizing that there is a theoretical limit to the productivity that can be taken from the oceans and that we may currently be at or approaching that limit, National Academy of Sciences 2006. Dynamic Changes inMarine Ecosystems: Fishing, Food Webs, and Future Options

  13. What do we have to adapt to? • Loss of abundance • Loss of biodiversity • Changes in distribution of species • Changes in productivity of ecosystems • Changes in species composition • Changes in variability from year to year and place to place • Changes in resilience (the ability of ecosystems to recover

  14. Lessons Learned (from Ram and others) for the Future of Fisheries • Beware the false dichotomy between environmental changes or fishing effects. Both are inevitably affecting resources • As species composition, ranges and productivity shift, fisheries will adapt to those changes, very rapidly • If management continues on a course of reducing flexibility, both management and fisheries will fail • If fisheries are to be flexible, overcapacity is intolerable

  15. More Lessons… • It is ecosystems that will undergo changes, not just individual stocks, so an ecosystem-based approach is essential • Ecosystem plans must be adaptable to changing conditions. It will be impossible to adapt one species at a time • Pushing to the limits of exploitation for each species or in each circumstance is incredibly risky. Be careful

  16. If management continues on a course of reducing flexibility, both management and fisheries will fail

  17. George’s Bank Cod

  18. Gulf of St. Lawrence Cod Landings and TAC’s for Northern Gulf of St. Lawrence cod. Canada Dept. Fisheries and Oceans 2007

  19. Is fishing affecting the rebuilding ??Gulf of St. Lawrence Cod 2003 1996 1995 1998 1994 2004 2006 1997 2002 2001 2005 2000 1999 Courtesy A. Frechet, DFO Canada

  20. If fisheries are to be flexible, overcapacity is intolerable

  21. P. Dengbol As species composition, ranges and productivity shift fisheries will adapt to those changes, very rapidly

  22. Political Pressure to Keep Fishing

  23. P. Degnbol

  24. P. Degnbol

  25. When fishing pressure remains high, stocks show little recovery Rosenberg et al. 2006. Frontiers in Ecol. Env.

  26. When fishing pressure is reduced, stocks can recover Rosenberg et al. 2006. Frontiers in Ecol. Env.

  27. Incentives • Current incentives are to resist restrictions not make them work. • The privilege to fish must be linked to conservation performance. • Incentives must be changed to support conservation through linking compliance to access. • The fishing does not exist in isolation. Changing policies to consider all impacts changes the dynamics of policy-making

  28. Can Catch Shares Prevent Fisheries Collapse? C. Costello, S. D. Gaines, J. Lynham Science 2008

  29. Shifts Due to Climate, in Productivity and Susceptibility Expected for Species within regions Productivity and Susceptibility Analysis Adapted from Hobday

  30. Precautionary Measures to Prevent Overfishing

  31. Science 2006

  32. Bald Rock Ground 6356 518 Eastern Bay Egg Rock Broken Ground 4595 1269 Turtle Island Shoals Inner Blue Hill Bay 14345 4053 Martin’s Ridges 250 Cranberry Isles Harbor Bass Harbor 99 Fishing grounds identified from logbooks Almost all are near shore, many are well within bays. Centroids of New Fishing Grounds identified from fishing logs Number of Cod landed on small grounds near Mt Desert in 1861. Near shore areas were essential cod habitat in the mid-1800s. Average distance from shore for previously unrecorded, mid-19th century fishing grounds = 9.27 km Average distance from shore for grounds mentioned in Rich (1929) = 22.59 km

  33. Changing Productivity From W. Leavenworth, UNH

  34. Ocean ecosystems provide many services,most of which are undervalued • Food • Medicines • Recreation & tourism • Trade • Education & research • Water purification • Shoreline protection • Nutrient cycling • Moderation of climate • Cultural, spiritual, and religious values

  35. Five Features of EBM • Common goal – conserve ability of the ecosystem to provide a full suite of services • Manage based on natural, not jurisdictional, boundaries • The sectors of human activity interact so management should be integrated • Impacts of human activities on an ecosystem are often cumulative across both time and space • Tradeoffs in services among sectors must be made and should be explicit

  36. It is ecosystems that will undergo changes, not just individual stocks, so an ecosystem-based approach is essential Rosenberg & MacLeod 2005

  37. Changing Uses

  38. Scientific Consensus Statement on Marine Ecosystem-Based Management WHAT IS ECOSYSTEM-BASED MANAGEMENT FOR THE OCEANS? Ecosystem-based management is an integrated approach to management that considers the entire ecosystem, including humans. The goal of ecosystem-based management is to maintain an ecosystem in a healthy, productive and resilient condition so that it can provide the services humans want and need. Ecosystem-based management differs from current approaches that usually focus on a single species, sector, activity or concern; it considers the cumulative impacts of different sectors.

  39. Is the whole greater than The sum of the parts?

  40. Lessons Learned (from Ram and others) for the Future of Fisheries • Beware the false dichotomy between environmental changes or fishing effects. Both are inevitably affecting resources • As species composition, ranges and productivity shift, fisheries will adapt to those changes, very rapidly • If management continues on a course of reducing flexibility, both management and fisheries will fail • If fisheries are to be flexible, overcapacity is intolerable

  41. More Lessons… • It is ecosystems that will undergo changes, not just individual stocks, so an ecosystem-based approach is essential • Ecosystem plans must be adaptable to changing conditions. It will be impossible to adapt one species at a time • Pushing to the limits of exploitation for each species or in each circumstance is incredibly risky. Be careful

  42. From Robert Wilson: The Hidden Assassins (2006) “You’re smiling, Javier…. I’m impressed ‘I’m solitary but not depressed’, said Falcon. ‘That’s not bad going for a middle-aged homicide detective’, said Pablo. ‘Being a homicide detective isn’t such a problem for me. There aren’t that many murders in Seville and I crack most of them, so my work with the homicide squad actually gives me the illusion that problems are being resolved. And, as you know, an illusory state can contribute to sensations of well-being,’ said Falcon. ‘If I were trying to resolve something like global warming, or the oceans’ dwindling fish stocks, then I’d probably be in much worse mental shape.’

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