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The BP oil spill turned out to be less disastrous than people feared at the beginning, but it still was a disaster, and the effects are still being felt. Dolphins in the Gulf of Mexico are getting very sick, we're told, from exposure to oil. For the first time, a government study confirms a host of problems in dolphins who live in one of Louisiana's bays worst affected. Here's NPR's Debbie Elliot.
DEBBIE ELLIOT, BYLINE: In 2011, the year following the disaster, scientists examined bottlenose dolphins in Barataria Bay. The South Louisiana estuary was hit hard by the oil spill, and remains an area where oil shows up on beaches and wetlands. Researchers say they discovered gravely ill dolphins.
LORI SCHWACKE: We just haven't seen animals that were in such bad shape as what we saw in Barataria Bay. I mean, nearly half of them (unintelligible) the worst prognosis.
ELLIOT: Lori Schwacke is with NOAA's Centers for Coastal and Ocean Sciences and a lead author of the study. She says they found a high prevalence of serious health issues.
SCHWACKE: Many of the Barataria Bay dolphins were underweight. Their blood tests showed abnormalities such as elevated liver enzymes or markers of inflammation. Many were hypoglycemic, which is low glucose or low blood sugar, and several were anemic.
ELLIOT: Symptoms consistent with the toxic effects of exposure to petroleum hydrocarbon, she says. The study, published in the journal Environmental Science and Technology, is the first evidence that the BP oil spill made marine mammals sick. The health of the Louisiana Dolphins was compared to the status of bottlenose dolphins in Sarasota Bay, Florida, which did not suffer direct oiling from the 2010 disaster.
The Barataria dolphins were five times more likely to have lung disease, including masses in the lungs and pneumonia. Schwacke says they also had unusually low levels of adrenal hormones, the ones that respond to stress.
SCHWACKE: To conduct these assessments, we had to encircle the dolphins with a net. And the dolphins would usually hit into the net, trying to escape. And at that point, we'd have a team of human handlers jump into the water and restrain the animals. So you can imagine that in a wild animal, this would prompt an acute stress response.
ELLIOT: It did not in these dolphins. The study is part of the natural resource damage assessment, an ongoing federal research project to determine the oil spill's harm to the environment. Debbie Elliot, NPR News. Transcript provided by NPR, Copyright NPR.