Many bottlenose dolphins in Barataria Bay are underweight, anemic, have low blood sugar and/or some symptoms of liver and lung disease, the National Oceanographic and Atmospheric Administration reported Monday.
The findings are the result of a study of 32 live dolphins conducted in the summer of 2011 in the bay in the northern Gulf of Mexico.
NOAA biologists found that nearly half of the dolphins also had abnormally low levels of hormones that help with stress response, metabolism and immune function.
Some of the study dolphins are in such poor health they will likely not survive, researchers said.
Since February 2010 more than 675 dolphins have stranded themselves in the northern gulf -- from Franklin County, Fla., to the Louisiana/Texas border -- a rate significantly higher than the usual average of 74 dolphins per year, NOAA biologists said.
The study is part of the Natural Resource Damage Assessment to analyze the effects of the oil spill, and is being conducted by NOAA with local, state and federal partners