Blair Mase of the National Marine Fisheries Service said that dolphin carcasses had been found in Louisiana, Mississippi and Alabama since May 2. Samples have been sent for testing to see whether the massive oil spill in the Gulf of Mexico was to blame for their deaths.
Mr Mase and animal rescue coordinator Michele Kelley in Louisiana said that none of the carcasses had obvious signs of oil. Mr Mase also said it's common for dead dolphins to wash up this time of year when they are in shallow waters to calve.
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Barack Obama's other war on terrorMoby Solangi, director of the Institute for Marine Mammal Studies, said his agency found one of the dolphins on the north side of Horn Island in Mississippi. He said the body was decomposed.
"We have this additional factor (oil spill) going on, so that will be tested," Mr Solangi said. "We are not leaving that factor out and they are being tested."
There are 3,000 to 5,000 dolphins in and around Mississippi waters and an estimated 75,000 in the Gulf of Mexico. Federal officials reported that about a dozen birds, fouled and sickened by oil, had been rescued, and that two had been rehabilitated enough to be released.
Dozens of dead sea turtles have also been found.