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The Honolulu Advertiser

Posted at 9:41 a.m., Tuesday, March 27, 2007

White-tailed eagle's visit to Kaua'i a 'phenomenon'

By Keya Keita
The Garden Island

LIHU'E, Kaua'i — "It's a natural phenomenon when a new species shows up on an island," said Brenda Zaun, referring to the recent confirmed visit of a white-tailed eagle to Kaua'i.

The threatened bird, typically from coastal Europe (Norway, Iceland, Poland and Greece) or Siberia and the northern Asia region, has flown thousands of miles to arrive on our shores.

"This is history in the making," said Zaun, who is almost sure the feathered raptor flew on its own from some other distant land mass to Kaua'i.

The Garden Island reported that Zaun, a wildlife biologist with the U.S. Fish and Wildlife Service, feels fortunate to have witnessed the bird's visit.

Known also as the white-tailed sea eagle, it is a huge bird that can have a wing span of up to 8 feet. According to Great Britain's Forest commission, the eagle typically nests in trees rather than cliffs.

Fish and seabirds, like albatross and ducks, make up the diet of the eagle; when hunting for fish, the white-tailed eagle prefers to watch from a suitable perch, then swoop and pluck the fish from the surface of the water without getting wet. The eagles also scavenge, scouring the shoreline for washed up fish and often steal food from other birds.

Despite having witnessed one albatross kill by the eagle on Kaua'i and confirmed a report of two others killed, Zaun is not concerned that the eagle is a threatening predator for the island's bird population.

"Humans remain the major threat for our bird population. Even if the eagle was to eat 10 albatross, that would only be 10 percent of this year's new population. It really isn't an issue to be concerned with," she said.

Reading up on the bird of prey, Zaun said, "There was one sighted in Alaska in 2006, and another eagle that lived on Kaua'i for 17 years several years ago. But that one was reportedly killed by a helicopter."

While German ornithologists believe that the bird was hunted in the beginning of the 20th century for its magnificent feathers and egg size, today, it is threatened by indirect factors such as heavy metal intoxication, collisions with railway trains and power lines.

The eagle, which has no specific animal predator, is considered to hold a top spot in the food chain.

When one of the these "top" animals, in any ecosystem, shows signs of rapid population decrease, it is considered a "reasonable bio-indicator" that there are heavy toxins deep within the chain itself.

Current studies, using GPS collar tracking, are helping scientists understand this beautiful and threatened species, but much of the information is still elusive.

"It's really spectacular to see one here," said Zaun. "Bird watchers from the other islands have come to Kaua'i to see if they can catch a glimpse of this beautiful, protected animal."

Zaun believes the bird has been here since early December when a volunteer for the refuge claimed to have seen it. Another sighting, confirmed by photograph last week, was on the South Shore — breaking the pattern of the bird having only been seen on the North Shore.

"Before this last time, we've only heard it being seen around here. I hope anyone who sees it can take a photo and contact me," Zaun said.

When asked why she thinks it came to Kaua'i, Zaun can only speculate.

"When a sea bird is on such a long flight, land means possible food. He seems to be very skittish of people, so I am pretty sure he was not from any captive environment. Most probably he is just looking for food and a rest," she said.

Mike Walther, owner of O'ahu Nature Tours, has been on Kaua'i for three weeks trying to spot and photograph the eagle.

"I'm fairly sure it's gotten here on its own as these birds have been known to fly 2,000 miles. It's possible the bird hopped from island to island from Siberia, but since there were no other reported sightings, it's anybody's guess," he said.

Walther, a naturalist and photographer who tries to add new birds to the Hawaiian check-list of bird species sighted in the islands, is excited to place the eagle on this year's list.

"This is a welcome addition and even though we didn't see the eagle ourselves, we are happy to have a confirmed sighting of this bird that lived here thousands of years ago. Sub-fossil bones have been found on Kaua'i that prove this species of bird once lived here," Walther said.

Over the past few weeks Zaun has worked with many birders who are hoping to see the eagle.

"Brenda has been so wonderful and helpful to us," Walther said. "We were here to also document a snow goose on the West Side, and a pair of tundra swans near Lihu'e.

"Our Web site shows over a hundred Hawaiian birds and we are happy to add these two species — our company is dedicated to conservation through education. We believe by showing residents and visitors the beautiful array of bird species here, we can inspire them to get involved with their plight to survive and thrive."

Coincidentally, this Friday the foremost scholar on ornithological DNA and fossil research is coming to Kaua'i to give a lecture.

Storrs Olsen published a paper in 2000 introducing the DNA proof of the white-tailed eagle's ancient Kaua'i home, separating it from the bald eagle through DNA research.

Whether the eagle is visiting, here to stay, or welcoming a scientist who has only long studied cave fossils that illuminate its old stomping grounds, "It really could be just the first chapter in what may become a 15-year-story of the eagle's new residence on Kaua'i," Walther said.

For more Kaua'i news, visit The Garden Island.