Migrating Manatees Threatened by BP Oil Spill

The BP Deepwater Horizon offshore oil spill, widely regarded as the worst ecological disaster in U.S. history, continues to leak crude oil into the Gulf of Mexico.Although efforts are underway to stop the leak and keep oil off beaches and out of estuaries, much remains unknown about the potential impacts to wildlife, in particular West Indian manatees (Trichechus manatus).

Biologists in 2007 documented that as many as 100 West Indian manatees leave peninsular Florida and travel west to spend the summer in Mobile Bay, Alabama.This migration puts these endangered marine mammals at risk of exposure to oil leaking from BP’s Deepwater Horizon well and dispersants being used to scatter the oil.

Due to their behavior, manatees are especially at risk to oil.Manatees, like all mammals, breathe air and must surface regularly, which could put them in contact with toxic chemicals and fumes.Manatees are also herbivorous and eat up to 10% of their body weight a day in sea-grass and other aquatic vegetation, making the potential for ingestion of contaminated food a concern.Additionally, if a manatee were to become injured by oil or dispersant, rescue would be extremely difficult due to the animals’ large size.

As the summer continues, the impacts of this spill on manatees in the Gulf of Mexico will become clearer. Manatee biologists hope to avoid similar results to a 1983 oil spill in the Persian Gulf.In that spill, 38-60 dugongs, a close relative of the manatee, were killed as a result of exposure to oil.