Miscount of animals harmed by spill may limit BP fine, study says

BP's oil spill in the Gulf of Mexico killed or sickened up to 200 times the number of animals estimated by the government, an undercount that could limit the company's spill-related fines, an advocacy group said.

The Center for Biological Diversity, an environmental group based in Tucson, Ariz., said in a study released Tuesday that it estimates five times as many sea turtles, 10 times as many birds and 200 times more marine mammals were injured or died than officially estimated. BP faces civil penalties based, in part, on the number of wildlife and fish killed or harmed by more than 4.1 million barrels of crude that poured into the Gulf last year.

The government's counts haven't been updated to reflect the dozens of bird, turtle and dolphin carcasses washing ashore this spring, Tierra Curry, a biologist with the center, said in the report.

The group added those casualties to the official tallies and then multiplied those numbers "by accepted scientific multiplication factors" to reach what it calls the "true mortality counts," she said.

U.S. tallies released in mid-February counted wildlife harmed by the spill to include 1,146 sea turtles, 8,209 birds, and 128 dolphins and whales, Curry said, citing government data.

By the center's estimate, the spill caused harm or death to about 6,165 sea turtles, 82,000 birds of 102 species and up to 25,900 marine mammals, including four species of dolphins and whales.

Scientists working for environmental groups and government agencies have been conducting separate studies. The studies rely on multipliers, as scientists say exact counts of killed or sickened animals are impossible, given that most carcasses sink into the ocean, rot unseen in marshes or are consumed by predators, according to Curry.

The center has filed a suit against London-based BP for Clean Water Act violations. It also has sued the Interior Department over offshore-drilling policies' impact on wildlife. Both lawsuits are pending along with hundreds of cases against BP and other companies involved in the oil spill. The suits were consolidated in New Orleans federal court.

"The Center for Biological Diversity's is an independent study," Wyn Hornbuckle, a Justice Department spokesman, said in an email.

"The government's investigation and assessment of damages to natural resources and wildlife is ongoing."