Federal wildlife officials said Monday that the deaths of thousands of seabirds in Western Alaska this summer was because of starvation, as they investigate a fifth straight year of unusually high numbers of seabird fatalities amid warm sea surface temperatures.
Thousands of short-tailed shearwaters were reported dead and washing onto beaches in the Bristol Bay region starting in late June, the National Park Service said in a statement on Monday.
As the summer continued, the deaths of the dark-colored birds extended to the Chukchi Sea off Northwest Alaska.
“Initial results indicate starvation as the cause of death for most locations,” said the agency, which is working with the U.S. Fish and Wildlife Service to track the deaths.
“Puffins, murres, and auklets are also being reported, but at much lower numbers than shearwaters,” it said.
Seabird die-offs have been known to occur in Alaska, but large numbers of different varieties of seabirds have been found every year since 2015, with starvation blamed. The die-offs have come as Alaska waters continue to be warmer than normal, the NPS says, potentially impacting sea life the birds eat.
In Southeast Alaska, the agencies blamed a “localized die off" of breeding arctic terns in June on exposure to saxitoxin, a biotoxin associated with paralytic shellfish poisoning.
“Analyses of tissue samples for harmful algal bloom toxins are ongoing and results will be shared as they become available. To date there has been no evidence of disease,” the statement said.