BP’s 2010 oil spill contributed to conditions that led to the deaths of hundreds of dolphins in the northern Gulf of Mexico, a new study conducted by half a dozen Southern universities and research institutes concluded.
The study, published in the journal PLoS One, points to three manmade and environmental stresses that formed a recipe for disaster for dolphins living along the Northwestern Florida, Alabama, Mississippi, and Louisiana coasts: the BP oil spill, which erupted off the Louisiana coast and released more than 200 million gallons of oil into the Gulf; the unusually cold winter of 2010; and an influx of cold, fresh water from snow melt in January 2011.
Dolphins are normally capable of surviving unusually cold conditions, but many of the dolphins in the northern Gulf were in poor health with thin layers of blubber following the BP oil spill.
Researchers involved in the study were careful not to blame BP outright for all the dolphin deaths, but they acknowledged a growing body of evidence that found the oil and the chemicals used to disperse it flooded the marine environment and coastal ecosystems, negatively impacting the food web. At the same time, the Gulf food chain may have been further diminished by colder than normal conditions excessive fresh water from snow melt arriving by river.
More than 750 dolphins have washed ashore since February 2010, more than twice the average rate. A spike in baby dolphin deaths occurred in January 2011, and dolphins continue to die in higher than normal rates along the Gulf Coast, with the exception of Florida, where the deaths have ceased.
In March, the National Oceanic and Atmospheric Administration released its report on autopsies performed on a group of Louisiana dolphins, which revealed abnormally low levels of a stress hormone and adrenal insufficiency – a condition linked to oil contamination among mammals in other studies.