Creatures of Habit: Albatrosses have returned to Vancouver Island every year for thousands of years

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The short-tailed albatross was a creature of habit, according to a new study that has found it returned to Vancouver Island to feed for generations over a 4,200-year period before being driven to the precipice of extinction by feather hunters.

The evidence could be the key to helping birds recover from extinction, said the study’s lead author, Eric Guiry, a senior lecturer at the University of Leicester in England.

The birds’ potential ranges span thousands of miles of wide open spaces along the Pacific coast and across oceans, but Guiry said the animals still prefer certain hunting and feeding grounds.

“This type of feeding behavior was only recently discovered in birds today,” he said in an interview. “But we have evidence that this happens over thousands of years. The same birds go to the same area all their lives.”

A short-tailed albatross in flight. The species is known for its distinctive pink beak. (ajmatthehiddenhouse/Creative Commons)

Researchers analyzed the birds’ foraging patterns using chemical fingerprints, or isotopic compositions, preserved in albatross bones discovered during archaeological digs and museum samples, according to the study published this week. this month in the open-access journal Communications Biology.

One of the sites where researchers collected ancient bone samples, a Mowachaht Nuu-chah-nulth village on Nootka Island off the west coast of Vancouver Island, dates back to 2300 BC. The study compared samples found on Vancouver Island with those from the United States, Russia and Japan.

Scientists were able to connect various dots with the chemical fingerprints to piece together the puzzle of the short-tailed albatross’ 4,250-year migration and feeding pattern, Guiry said.

By mapping biological markers against known isotopic baselines in the species’ foraging range – which was thousands upon thousands of miles each year of migration – researchers were able to paint a picture of migratory behavior. and foraging birds over hundreds of generations, he said. .

The birds’ foraging behavior gives researchers insight into their vulnerability, he said.

The short-tailed albatross was nearly wiped out for its feathers between the 1880s and 1930s, leaving no functioning breeding colonies in the North Pacific, from Japan to Russia, from Vancouver Island to southern California, according to the study.

Known for its pink beak, the wingspan of the albatross can exceed two meters. Their white and gray feathers turn yellow on the head.

Once numbered in the millions, seabirds are rebounding, but they remain at less than 1% of their pre-collapse level. The birds are listed as threatened by the Committee on the Status of Endangered Wildlife in Canada.

“As population growth continues, understanding the factors that govern how and where short-tailed albatrosses select and allocate their time among specific foraging areas may be critical to developing effective conservation approaches,” the study says. .

A male and female short-tailed albatross. Albatross numbers are now less than one percent of what they were before widespread feather hunting. (USFWS Pacific/Creative Commons)

Guiry said the birds will have “good reasons” to return to the same places to find food. He said it was unclear at the time what the birds ate, but they knew squid was part of their diet.

“These will be particularly rich hotspot areas for foraging. This happens particularly where there is upwelling and strong winds, so a lot of nutrient-rich water is coming up, and that’s important for the types of foods they crave.”

This behavior could return as the population rebounds, he said.

“The fact that it seems to be happening to such a degree for so long makes you wonder if something more fundamental is going on.”

What surprised him the most, Guiry said, was the unchanging path and pattern.

“Just the distance they travel thousands of miles to the same types of areas,” he said. “The fact that a species travels huge distances, and that happens from generation to generation for thousands of years. It’s just a remarkable degree of consistency.”

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