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Dramatic introduction!

Dramatic introduction!. OVERFISHING OF ATLANTIC BLUEFIN TUNA ( Thunnus thynnus ). Implications and Conservation Strategies Nick Gezon, Linda Isakson, Laura Pratt, and Alex Lee. GENERAL OVERFISHING. 16.6% of animal protein consumed $80 billion/ year industry

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Dramatic introduction!

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  1. Dramatic introduction!

  2. OVERFISHING OF ATLANTIC BLUEFIN TUNA(Thunnus thynnus) Implications and Conservation Strategies Nick Gezon, Linda Isakson, Laura Pratt, and Alex Lee

  3. GENERAL OVERFISHING 16.6% of animal protein consumed $80 billion/year industry Employs ~750 million people worldwide Catch peaked in late 1990s at 90 million tonnes, now at 77 million tonnes as a result of exploitation Bottom-trawling, dredges, traps have damaged or altered 95% of marine habitats 85% of global fish stocks depleted Illegal, unregulated and unreported (IUU) main culprit

  4. ATLANTIC BLUEFIN TUNAOVERFISHING 61% of tunas are either overexploited or fully exploited worldwide Used as dog food prior to 1950s, then technology improved delivery Use in sushi and sashimi exploded market from 20,000 tonnes/yr harvest to over 80,000 tonnes/yr at peak. Western Atlantic population reduced to 17% of 1950's biomass Eastern Atlantic population reduced to 33% of 1950's biomass

  5. ATLANTIC BLUEFIN TUNAOVERFISHING • Western Atlantic or Gulf of Mexico stock • Eastern Atlantic or Mediterranean Sea stock • *Horizontal dashed lines represent the stock biomass necessary for maximum sustainable yield.

  6. ECOSYSTEM IMPLICATIONS

  7. ECOSYSTEM IMPLICATIONS • Bluefin Tuna are apex predators in the Atlantic pelagic ecosystem. • They feed on mackerel, squid, herring, and sardines. • They have a top-down effect on the food web controlling prey populations. • Overfishing of bluefin tuna has caused populations of prey to become unstable (Boom and Bust Cycles) • This threatens the health of the whole ecosystem. • A study assessing the risks for global fisheries health found that changes in lower trophic level prey fish populations pose the greatest threat to fisheries collapse(Pinsky et al. 2011)

  8. COMMUNITY STRUCTURE

  9. ECONOMIC IMPLICATIONS • High Demand with depleting populations • The Japanese Market • Annually 500 million USD • Prices average $100K • Fish at breeding locations • Ricardo Fuentes makes annually 220 million USD

  10. IUU FISHING • IUU: Illegal, unregulated, unreported fishing • The Japanese Market • Estimates 6-7 billion USD over last 20 years • Catching undersized fish • Misreporting number caught • Fishing in unregulated waters (North Africa)

  11. SPORTFISHING • Recreational fishing in Haterras region, North Carolina • Emerged in 1996 • For financial gain • Condition of capturing one legal-sized tuna • Survey found Hatteras Fishery made 5 million USD

  12. SPORTFISHING Kayak Angler unlawfully catches a bluefin tuna

  13. ATLANTIC BLUEFIN TUNAOVERFISHING • ICCAT created in 1969 to regulate bluefin harvesting • 40 years later, bluefin still in decline • IUU fishing still rampant but more stringent measures are being taken • Proposal to list T. thynnus under CITES rejected • Recently adopted 13,500 tonnes limit for 2013

  14. CONSERVATION MEASURES • Current: • Aquaculture– the farming of bluefin tuna • CleanSeas Aquaculture Growout • Spawning Sanctuaries • Protected habitats • Gulf of Mexico

  15. CONSERVATION MEASURES • Problems: • There is a significant amount of IUU (illegal, unreported, unregulated) • Bluefin are not optimal fish to farm • Biomass is so low that it’s hard to bounce back with continued fishing • Little international cooperation • Because of adverse affects on economy and culture

  16. CONSERVATION MEASURES • The future: • Continue placing regulations and bans upon fishing • Encourage international compliance • Trade embargos • Onboard monitors for IUU • Develop new methods of aquaculture

  17. RAISE AWARENESS!

  18. SOURCES Bohnsack, B.L., Ditton, R.B., Stoll, J.R., Chen, R.J., Novak, R., Smutko, L.S. 2002. The economic impacts of the recreational bluefin tuna fishery in Hatteras, North Carolina. North American Journal of Fisheries Management. Vol 22, Issue 1, p165-176. Center for Public Integrity. 2012. The black market in bluefin tuna. http://www.publicintegrity.org/2010/11/07/2335/overview-black-market-bluefin Ellis, R. 2008. The bluefin in peril. Scientific American. Vol298, p70-77. Ezzy, E., Scarborough, H., Wallis, A. 2012. Recreational value of southern bluefin tuna fishing. Economic Papers: A Journal of applied economics and policy. Vol31(2), p150-159. Fromentin, J.M., Powers, J.E. 2005. Atlantic bluefin tuna: population dynamics, ecology, fisheries and management. Fish and Fisheries. Vol6, p281-306. International Commission for the Conservation of Atlantic Tunas. Statistical Bulletin 40, 1960-2009. July 2011. Kato, Dawn, M. 2011. The Battle for Bluefin: The Consumers Role in Preserving the Atlantic Bluefin Tuna. California Western International Law Journal. Vol 42, Issue 1, p149-188. Pinsky M.L., Jensen O.P.,Ricard D., Palumbi S.R. 2011 Unexpected patterns of fisheries collapse in the world’s oceans. PNAS Ecology Polachek, Tom. 2012. Assessment of IUU fishing for Southern Bluefin Tuna. Marine Policy. Vol 36, p1150–1165. United Nations Conference on Sustainable Development. 2012. The Future We Want: Oceans. Rio+20 Factsheet.

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