Unusually warm ocean water may be causing seabirds to starve.
Editor's note: second of a two-part series.
Thousands of the dead seabirds have been washing ashore along the state’s coasts over the past several months. And Alaska Audubon spokeswoman Beth Peluso says hundreds of weak and emaciated murres have been spotted elsewhere around the state in areas they’re not known to frequent.
“Some of these birds that they’ve been finding are really starving,” Peluso said. “They’re not in good shape.”
[asset-images[{"caption": "Thousands of dead common murres have been found along beaches and other areas around Alaska in recent months. Scientists believe warm ocean water in the North Pacific has disrupted the usual circulation of water that brings plankton closer to the surface for small fish to eat. Murres usually feed on the small fish, but they've haven't shown up over the past year in the birds' usual feeding grounds along the continental shelf of western North America.", "fid": "4453", "style": "offset_right", "uri": "public://201601/murredieoff4.jpg", "attribution": "Credit U.S. Fish and Wildlife Service"}]]
Dead and dying birds also began showing up this fall on beaches along the Kenai Peninsula, south of Anchorage. Heather Renner, with the Alaska Maritime National Wildlife Refuge says that confirmed concerns biologists have had about the species since last spring’s unusually bad breeding season.
“At many colonies in the western Gulf of Alaska, murres completely failed reproductively,” Renner said. “And that’s really unusual.”
Migratory bird expert Robb Kaler says the murres left their long-time western breeding grounds well before the mating season usually ends. That’s never occurred since researchers began collecting data there in the 1970s.
“They’ve never seen a colony abandonment in the middle of the breeding season – essentially where the birds just give up,” Kaler said.
Kaler, a U.S. Fish and Wildlife Service biologist, says hunger probably interrupted the murres’ mating season. He says they likely flew far and wide in search of food, which would explain why emaciated birds have found as far north as Fairbanks, some 350 miles from the coast.
“I mean, all these things are pointing toward starvation – a lack of finding their food,” he said. “What we don’t know is the mechanism.”
Kaler says tests have pretty much ruled out disease and poisoning from for example toxic algal blooms. He says most scientists now believe a large area of abnormally warm water near the surface of the North Pacific, commonly referred to as “The Blob,” is the root cause of the die-off.
He says the warm water apparently has sharply reduced the number of capelin and other fish the murres eat in that area, because there’s less “upwelling” and circulation in warmer ocean water, which brings plankton up from lower depths for the fish feed on.
