Marine scientists are debating whether 80-plus bottlenose dolphins found dead along the U.S. Gulf Coast since January were more likely to have perished from last year’s massive oil spill or a winter cold snap. The National Oceanic and Atmospheric Administration declared “an unusual mortality event” last week when the number of dead dolphins washing up…

Marine scientists are examining the deaths of 20 baby dolphins whose carcasses have washed ashore in Mississippi and Alabama this year, the bulk of them since last week, researchers said on Tuesday. The unusually large number of young dolphin deaths are being looked at as possible casualties of oil that fouled the Gulf of Mexico…