Friday, February 11, 2011

ANCHORAGE, Alaska (AP) -- A Kodiak Island bald eagle survived 25 years of Alaska hazards but met an unfortunate fate last month on the crossbar of a utility pole: electrocution.

A band attached to its leg showed the bird to be the second-oldest bald eagle documented in Alaska and one of the oldest in the country.

"It would be, based on the bird-banding record that I've seen, one of the top 10 oldest birds ever recorded," said Robin Corcoran, a wildlife biologist from the Kodiak Island National Wildlife Refuge.

The eagle's death was first reported by the Kodiak Daily Mirror.

The death was of high interest to raptor biologists, who have no other way besides recovered bands to confirm the age of mature wild eagles.

"Once they reach that full adult stage - white head, brown body, white tail - you don't have any idea how old they are," said Steve Lewis, coordinator of raptor management for the Alaska region of the U.S. Fish and Wildlife Service.

The oldest eagle documented in the country was a 32-year-old bird from Maine. Alaska's oldest recorded eagle was a 28-year-old from the Chilkat Valley outside Haines. Lewis suspects most eagles don't approach three decades but proving that with leg bands can be haphazard.

"Banding is one of these things, you put a lot of effort into it and you get little return, but the returns you get are really interesting," he said.

The odds of recovering a band go up around communities such as Kodiak. The city is on the island of the same name, the second largest in the U.S. The Kodiak National Wildlife Refuge covers one-third of the island and has a resident population of 2,500 birds, but the city is a drawing card for other eagles.

Hundreds from mainland Alaska gather there each winter when lakes and streams freeze up. Eagles are opportunistic eaters, grabbing fish and small mammals, but America's national bird is not above Dumpster-diving or feasting on other tidbits from humans.

"The canneries and fish process plants, the commercial fishing, it's a real magnet," Corcoran said.



Kodiak's only road out of town crosses hills to the nation's largest Coast Guard base.

"When you drive that road, there are easily, every day, one hundred birds, just on the hillside, sunning themselves in the trees if it's sunny, or just trying to stay dry," Corcoran said. "And then if you look down at the canneries, right on the water's edge, there are another hundred, at least a hundred birds, perched on the cannery rooftops."

A garbage bag in the back of a Kodiak pickup will attract winged intruders. Fishermen mostly are conscientious, she said, but boats will draw birds.

"Sometimes when the fishing boats come in, the nets are spun up on the back deck, there will still be some fish in there. The birds are all over the nets. You can see a dozen birds on one boat, just on the nets," Corcoran said. "Usually they're accompanied by Steller sea lions that are climbing up in the back of the boat to see what's left on the back deck."

Fish bait is another temptation.

"Yesterday there was some bait left unattended on the back deck of a boat and that caused a frenzy," Corcoran said. "The birds ended up getting soiled and fighting over it, and then they fall into the water."

Oiled by fish slime, feathers are less waterproof and eagles are more prone to hypothermia, she said.

Refuge biologists have retrieved starved eagles and birds killed by airplanes, cars or leg-hold traps meant for fox. Sometimes there are mass mortalities.

Fifty eagles in January 2008 spotted an uncovered dump truck filled with fish guts outside a Kodiak seafood plant. Twenty drowned or were crushed. The rest were so slimed they had to be cleaned.

The refuge last year sent off 30 dead eagles to the National Eagle Repository northeast of Denver. Thirty to 40 eagle dead eagles recovered is typical, Corcoran said.

The electrocuted bird was captured in July 1989 as part of research project into possible health damage from the Exxon Valdez oil spill, which had occurred on March 24 that year.

"It was a beautiful older female," Corcoran said. The power pole near a cannery had been fitted with two devices designed to protect eagles but it perched on the lowest of three cross bars where utility authorities did not believe there was enough room to alight.

Lewis said there may be a new candidate for Alaska's oldest eagle. A dead eagle was found late last year on Adak Island in the Aleutians and may be as old as 29 1/2 years.

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