Atlantic bluefin tuna (seen schooling in an undated picture) are high on the list of species scientists have feared would be devastated by the Gulf oil spill.
As the most sought-after seafood, Atlantic bluefin populations had already plunged by 80 percent or more when the spill struck.
(See related pictures: "Tuna Demand Pressures Wild Stocks.")
In a worst-case-scenario for the imperiled western North Atlantic bluefin stock, the Gulf oil spill landed smack in the fish's only known spawning ground—right during the spawning season. Vulnerable eggs and larvae, along with adult fish, were undoubtedly exposed to toxic crude and chemical dispersants, experts say.
For now, the spill's effect on bluefin and other Gulf fish remains unknown, William Richards, a retired senior scientist for the National Marine Fisheries Service in Miami, said by email.
Last year, oil clogged nets used for collecting baby bluefin and sampling was interrupted, preventing a complete population estimate, said Richards, who has long studied bluefin larvae.
Scientists will begin sampling this year's larvae in late April, but no results will be available until late 2011.