An estimated 8,000 black and white seabirds, called murres, were found dead on a beach in Alaska earlier this month.
Their bodies were found floating in the surf and washed ashore in the Prince William Sound community of Whittier. Wildlife ecologist Dan Grear said this is the biggest die off of the common murre in Alaska this season, but not the first.
"Carcasses started to be noticed this fall in Alaska, and as the winter has progressed into December and early January, observers ... have started to find thousands of dead murres on specific beaches,” Grear said.
Grear works at the USGS National Wildlife Health Center in Madison, Wisconsin, which investigates animal health conditions and diseases.
"I think we've examined close to 100 of these [murres] that they’ve shipped down,” Grear said. “The consistent finding is that these murres are emaciated, they have very poor body condition."
Alaskan scientists have also observed live birds changing their flight patterns.
"They started to see murres show up farther inland on lakes and rivers, which suggests that the murres are having trouble finding appropriate food at sea,” Grear said.
Murres may be starving to death because of abnormally warm surface water temperatures in the North Pacific over the past year. The seabirds eat by diving into the water to catch fish, and have to consume the equivalent of 10 to 30 percent of their body weight every day.
Scientists believe the abnormally warm waters of the Pacific are either killing off the murres' prey, or pushing them into cooler waters.
"(The fish) could be too deep, they could be moving to areas in the ocean where the murres aren't used to finding them,” Grear said. “These are all now just hypothesis that the science folks up in Alaska are trying to figure out how to test."
As they figure out what's happening now, those scientists are also worried about what the warming Pacific waters of an expected 2016 El Nino will mean for both the murres and their aquatic prey.
From PRI's The World ©2015 Public Radio International