(MOBILE, Ala.) - Scientists are learning more about what caused nearly 200 dolphins to die and wash ashore in early 2011. It's the subject of a study published Wednesday in the international journal Plos ONE.
Their study centered around surges of snowmelt coming down the Mississippi River and into the Gulf and how they contributed to the death of young dolphins.
"There was a period where an unusual number of young dolphin were stranding," says Ruth Carmichael, Senior Marine Scientist at Dauphin Island Sea Lab.
Of the dolphins to wash ashore, almost all of them were infants or juveniles. According to the study, the standings peaked several weeks after each surge of water entered the Gulf.
"We found it wasn't just a Mobile Bay phenomena," she says. "It was particularly intense coming out of Mobile Bay."
Carmichael says it wasn't necessarily the cold water surges that directly killed the dolphins, but one of many stressors contributing to the spike in deaths.
"The 2009-2010 winter was a particularly cold winter, and then after that the Deepwater Horizon spill," she says. "Follow that up with another colder than usual and this case long-duration winter."
Many of the dolphins were also infected with a bacteria that causes a condition called brucellosis. Carmichael says it was essentially a perfect storm.
She says the results of the study will be beneficial to scientists working to learn about conditions in the Gulf and the events that have unfolded there in the past few years.
"That's the best you can hope for," she says.
You can view the full study here.