BLUEFIN TUNA Thunnus thynnus Implications and Conservation Strategies Nick Gezon Linda Isakson Laura Pratt and Alex Lee 166 of animal protein consumed 80 billion year industry ID: 799483
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Slide1
Dramatic introduction!
Slide2OVERFISHING OF ATLANTIC
BLUEFIN TUNA(Thunnus thynnus)
Implications and Conservation Strategies
Nick
Gezon, Linda Isakson, Laura Pratt, and Alex Lee
Slide316.6% of animal protein
consumed$80 billion/year industryEmploys ~750 million people worldwideCatch peaked in late 1990s at 90 million tonnes, now at 77 million tonnes as a result of exploitationBottom-trawling, dredges, traps have damaged or altered 95% of marine habitats85% of global fish stocks depletedIllegal, unregulated and unreported (IUU) main culprit GENERAL OVERFISHING
Slide4ATLANTIC BLUEFIN TUNA
OVERFISHING61% of tunas are either overexploited or fully exploited worldwideUsed as dog food prior to 1950s, then technology improved deliveryUse 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 biomassEastern Atlantic population reduced to 33% of 1950's biomass
Slide5Western Atlantic or Gulf of Mexico stock
Eastern Atlantic or Mediterranean Sea stock*Horizontal dashed lines represent the stock biomass necessary for maximum sustainable yield.
ATLANTIC BLUEFIN TUNA
OVERFISHING
Slide6ECOSYSTEM IMPLICATIONS
Slide7Bluefin 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)ECOSYSTEM IMPLICATIONS
Slide8COMMUNITY STRUCTURE
Slide9Slide10High Demand with depleting
populationsThe Japanese MarketAnnually 500 million USDPrices average $100KFish at breeding locationsRicardo Fuentes makes annually 220 million USDECONOMIC IMPLICATIONS
Slide11IUU: Illegal, unregulated, unreported fishing
The Japanese MarketEstimates 6-7 billion USD over last 20 yearsCatching undersized fishMisreporting number caughtFishing in unregulated waters (North Africa)IUU FISHING
Slide12Recreational fishing in Haterras region, North Carolina
Emerged in 1996For financial gainCondition of capturing one legal-sized tunaSurvey found Hatteras Fishery made 5 million USDSPORTFISHING
Slide13Kayak Angler
unlawfully catches a bluefin tunaSPORTFISHING
Slide14ICCAT created in 1969 to regulate bluefin harvesting
40 years later, bluefin still in declineIUU fishing still rampant but more stringent measures are being takenProposal to list T. thynnus under CITES rejectedRecently adopted 13,500 tonnes limit for 2013ATLANTIC BLUEFIN TUNA OVERFISHING
Slide15Current:
Aquaculture– the farming of bluefin tunaCleanSeas Aquaculture GrowoutSpawning SanctuariesProtected habitatsGulf of MexicoCONSERVATION MEASURES
Slide16Problems:
There is a significant amount of IUU (illegal, unreported, unregulated)Bluefin are not optimal fish to farmBiomass is so low that it’s hard to bounce back with continued fishingLittle international cooperationBecause of adverse affects on economy and culture CONSERVATION MEASURES
Slide17The future:
Continue placing regulations and bans upon fishingEncourage international complianceTrade embargosOnboard monitors for IUUDevelop new methods of aquacultureCONSERVATION MEASURES
Slide18RAISE AWARENESS!
Slide19Bohnsack
, 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. Vol 298, 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. Vol 31(2), p150-159.Fromentin, J.M., Powers, J.E. 2005. Atlantic bluefin tuna: population dynamics, ecology, fisheries and management.
Fish and Fisheries
.
Vol
6, 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
.
SOURCES