As part of the Natural Resource Damage Assessment (NRDA) study on effects of the Deepwater Horizon oil spill, the National Oceanic and Atmospheric Administration (NOAA) performed a study of Bottlenose dolphins in Barataria Bay, Louisiana. The study performed a comprehensive physical of 32 live dolphins in the Bay during the summer of 2011. Batararia Bay, located in the northern Gulf of Mexico, received heavy and prolonged exposure to oil during the Deepwater Horizon oil spill.
The results of the NRDA study are rather upsetting – many of the dolphin exhibited significant adverse health conditions that the researchers attribute to the oil spill. The dolphins were found to be underweight, anemic, have low blood sugar, and exhibit symptoms of liver and lung disease. More than half also showed low levels of hormones that deal with stress response, metabolism and immune functions.
The researchers, including NOAA marine mammal biologists, and local, state, federal and other research partners, fear that some of the study dolphins are in such poor health that they will not survive much longer. Tragically, one of the studied dolphins was found dead in January 2012.
The NRDA study follows a finding of an Unusual Mortality Event (UME) by NOAA. Since February 2010, 714 dolphins have stranded themselves on the shores of the northern Gulf of Mexico – the area from Franklin County, Florida, to the Louisiana/Texas border. These strandings represent a much higher rate than the typical 75 strandings that occur yearly. More information on the UME can be found here.