U.S. government tightens lid on dolphin death probe
Biologists contracted by the National Marine Fisheries Service to document spikes in dolphin mortality were ordered to keep their findings confidential.

DEATH TOLL: As of this week, scientists have counted nearly 200 bottlenose dolphin carcasses found since mid-January along the shores of Louisiana, Mississippi, Alabama and Florida, about half of them newly born or stillborn infants. (Photo: Mike Stewart/AP)






















