Using satellite data from the European Space Agency, researchers estimate that over 20% of juvenile Atlantic bluefin tuna in the Gulf of Mexico were killed by the BP oil spill. Although that percentage may not seem catastrophic, the losses are on top of an 82% decline in the overall population over the past three decades due to overfishing. The population plunge has pushed the International Union for the Conservation of Nature (IUCN) to categorize the fish as Critically Endangered, its highest rating before extinction.
Given the perilous state of bluefin tuna worldwide, the US National Marine Fisheries Service announced in September, following the BP oil spill, that it would consider listing the species under the Endangered Species Act.
"This study confirms our worst fears about the oil spill’s impacts on bluefin tuna and provides more evidence that this species needs the Endangered Species Act to survive," said Catherine Kilduff, an oceans program attorney with the Center for Biological Diversity. "The federal government could have predicted the effects of the spill during spawning season prior to the disaster; listing Atlantic bluefin tuna as endangered will prevent such an oversight from ever occurring again."
Conservation groups and marine biologists have been pushing for a ban on bluefin tuna fishing for years, but to date the bluefin tuna regulating body—the International Commission for the Conservation of Atlantic Tunas (ICCAT), has placed short-term industry demands over long-term population concerns, consistently overriding its own scientists' recommendations on quotas. Bluefin tuna hit another setback earlier in the year when a proposed trade ban failed the at the Convention on International Trade in Endangered Species (CITES) after heavy lobbying from the Japanese. Japan is currently hosting the Convention on Biological Diversity (CBD), an international event meant to develop plans to stem the loss of biodiversity worldwide.
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http://news.mongabay.com/2010/1019-hance_bluefin.html