A study published in the Proceedings of the National Academy of Sciences determined that exposure to oil from the BP spill last year in the Gulf of Mexico has led to developmental and reproductive issues in the gulf killifish.
National Wildlife Federation researcher Doug Inkley said similar effects were seen in wildlife following the Exxon Valdez oil spill in Alaska in 1988.
"The gulf killifish provides us with a reminder that oil's impacts on wildlife can't be separated from its impacts on people," he said.
Inkley's warning follows a notice from the U.S. Coast Guard in Louisiana that oil sheen near the sight of last year's spill is possibly from debris of the Deepwater Horizon oil rig, which sank in April 2010, triggering the spill.
The Coast Guard said it issued a notice to rig owner Transocean of the possible release of oil from the debris.
"This is part of the process we take whenever there is an oil sighting that cannot be immediately attributed to a specific source," Coast Guard Capt. Jonathan Burton said. "We will actively work with Transocean to discuss options to determine whether or not the wreckage is the cause."