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hoto of a Laysan Albatross pair at nest on Midway Atoll.
John Klavitter (US Fish and Wildlife Service) |
By Suzan Phillips
Last Updated Mar 14, 2011,
Published Mar 13, 2011
The Laysan Albatross, Wisdom, one of the world's oldest known birds, and her newly hatched chick, have survived a tsunami at Midway Atoll.14th March 2011 - Among the terrible human tragedy of the Japan earthquakes and the tsunami waves that have swept the Japanese coastline and across the Pacific ocean, comes a good news bird story.
Last week, news sources around the world celebrated Wisdom’s efforts to raise another chick when she is reported to be the oldest known albatross, at more than 60 years old.
Wisdom had returned safely to her nest on Sand Island to raise another chick in the Midway Atoll National Wildlife Refuge in the Pacific Islands.
Last Saturday, one of the tidal waves from Japan’s 8.9 magnitude earthquake hit Midway Atoll.
The islands of Midway Atoll include a large colony of Laysan Albatross and the second largest breeding population of Black-footed Albatross and these were nesting on the ground with eggs and chicks in the nests this week when the tsunami waves struck.
Tsunami washes away nests and chicks
Staff on Midway Atoll reported that the tsunami that hit Midway Atoll was about 1.4 metres high and flooded some parts of the island. At least some chicks and adult Laysan Albatross were killed and hundreds of chicks were washed away from their nests onto roadways and under bushes. The nests inland were not affected, and by the morning both the adults and chicks there were going about their business as usual, according to one report.
Volunteers and visitors to the island spent the afternoon freeing dozens of albatross chicks that had been washed into and caught inside thickets of naupaka. This often required hacking through the bushes with large clippers and small saws, and either crawling through the spaces or climbing on top of the branches to perch suspended over the ground. Visitors also dug out many petrels who had been trapped and buried in their burrows.
Wisdom had a nest in the inland area, and so was safe. The first Short-tailed Albatross to nest on hard hit Eastern Island was also out of danger.
Kure Atoll colonies also devastated
The colony on Kure Atoll (89km east of Midway), was also devastated. Field Camp manager, Cynthia Vanderlip from Kure Atoll Conservancy said they climbed up onto the roof of their building.
“We are all fine. We stayed on the roof from 12pm until 4 am (on March 11th). Midway called and said that the wave had passed. ... I took a quick walk to see the damage at the beach and it is extensive. The wave washed about 400 feet inland,” she said.
“The Black-foot colony at the pier is gone, chicks are everywhere. Thousands of ghost crabs are cleaning up the dead. The wave washed over the top of the pier and tore the window frames out. The ocean is chocolate brown.”
“I am thankful that our building is 700 feet inland and 20 feet above sea level. We were spared, but I fear for all the other folks in the Pacific. The loss of wildlife breaks my heart. Thanks for your thoughts and prayers,” she said.
News came through to them later on that Wisdom and her chick, as well as the nest of the first Short-tailed Albatross to nest at Midway, had all survived the tsunami.
An albatross with a long record
Biologists suspect that Wisdom’s age may be double or triple the expected life span for a Laysan albatross, but were still gathering information and learning about the species.
Wisdom is the oldest wild specimen in American records, documented during the 90-year history of the US and Canadian bird-banding research program. A US Geological Survey scientist first tagged the bird with an aluminum identification band when she was about 5 years old in 1956 as she was incubating an egg. Since then, Wisdom has logged more than three million flying miles - the equivalent of six round trips to the Moon.
"It's really exciting to see that these birds are long-living and still raising chicks at 60 years old or older," said
US Fish and Wildlife Service biologist, John Klavitter, who spotted Wisdom with her chick in February.
Sand Island is the largest piece of land in the Midway Atoll area. Midway is a tiny US territory that lies about a third of the way between Honolulu and Tokyo in the North Pacific. The chick, whose gender is unknown at present, was doing well. Wisdom and her mate were taking turns feeding it, and the young bird will soon be banded, said Klavitter.
“Wisdom has probably raised about 35 chicks during her lifetime. Her species generally mates with one partner for life and lays only one egg at a time”, he said. Wisdom also nested in 2006, 2008, 2009 and 2010.
Many threats to breeding success
Wisdom has had five bird bands since she was first banded by
US Geological Survey scientist Chandler Robbins in 1956 as she incubated an egg. Chandler rediscovered Wisdom in 2001.
In 1956, he estimated Wisdom to be at least five years old then, since this is the earliest age at which these birds breed, though they more typically breed at 8 or 9 after an involved courtship lasting several years. This means, of course, that Wisdom is likely to be in her early sixties.
“Wisdom is now the oldest wild bird documented in the 90-year history of our USGS-FWS and Canadian bird banding program,"said Bruce Peterjohn, the chief of the North American Bird Banding Program.
"To know that she can still successfully raise young at age 60-plus, that is beyond words. While the process of banding a bird has not changed greatly during the past century, the information provided by birds marked with a simple numbered metal band has transformed our knowledge of birds," he said.
Albatross lay only one egg a year, but it takes much of a year to incubate and raise the chick. After years in which they have successfully raised and fledged a chick – which on Midway is about two-thirds of the time – the adults may take the occasional next year off from parenting.
Laysan albatross also breed on the Hawaiian islands of Oahu, at Kaena Point, and on Kauai, at Kilauea Point. They feed in areas off the west coast of North America, including the Gulf of Alaska, and spend their first three to five years constantly flying, never touching land. Scientists believe they even sleep while flying over the ocean.
Nineteen of the world’s 21 albatross species are listed as threatened with extinction from a variety of causes, including lead poisoning. On Midway Atoll, injuries from longline fishing, climate change and ingestion of garbage floating on the ocean threaten the area’s albatross species.
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