Dead bottlenose dolphin from GRN trip to coastal Louisiana, May 17, 2011. (cc) GRNThe BP oil spill appears to have profoundly impacted the 28 species of dolphins, whales and porpoises that inhabit the Gulf of Mexico. Since April 30, 2010, ten days after the disaster at the Macondo rig, 558 of these mammals have been found stranded along the Gulf coast, almost all of them dead. In 2011, strandings quintupled the annual average from 2002 to 2009.The spill has impacted the health of bottlenose dolphins. A recent study by NOAA examined 32 dolphins in Barataria Bay and found them to be in incredibly poor health. They were underweight and anemic, had low blood sugar and possessed signs of liver and lung disease.The Gulf’s endangered population of approximately 1700 sperm whales is in particular danger. Because of their low birth rates, scientists estimate that the long-term survival of this population would be in serious jeopardy if as few as three whales were killed by human-induced causes. The spill exposes sperm whales to the risk of poisoning and drowning. The harmful effects on whales’ prey also impair the whales’ ability to feed. Three sperm whales have been found dead since February 1, 2010.Sperm whale in the Gulf. Three have been found dead since the BP disaster, threatening the recovery of this endangered species. August 19, 2011. Photo (cc) GRN.The most disturbing fact of all is that the number of mammals found stranded likely dwarfs the true number killed or otherwise harmed by the spill. One study finds that true number of dolphins and whales killed may be as high as 50 times the amount of carcasses found. The study estimates different multipliers for different species. The number of sperm whales killed may be almost thirty times the number of carcasses recovered. Hundreds of dead marine mammals quickly becomes thousands of animals killed by BP.Lost in all of these statistics is the incredible tragedy of this mass death of dolphins and whales. Fishermen who routinely patrol the waters of the Northern Gulf face this heartbreaking reality on a daily basis. Some of these majestic creatures, such as the bottlenose dolphin, are believed to be among the most intelligent species in the animal kingdom, capable of a variety of cognitive tasks far beyond most animals. Despite their intelligence, however, they could not escape the drastic effects of such an enormous man-made tragedy. One Houma fisherman after finding a dead whale and bemoaning the tragedy of his day-to-day routine to community advocate Kindra Arnesen said “Two years later, nothing but death.” For more information on the effect of the oil spill on marine mammals, see this memo. Joe Lustig is a policy intern at GRN. He is currently pursuing his BA in American Politics and Economics at Tulane.