Chemical analyzes performed on these archaeological specimens of the short-tailed albatross in this undated image to investigate long-term behavioral trends. Eric Guiry / The Canadian Press
Short-tailed albatrosses are habitual creatures, according to a new study that found they returned to Vancouver Island to feed for generations for 4,200 years before being brought to the brink of extinction by feather hunters.
Evidence may be the key to helping birds return from extinction, said lead author Eric Guiri, a professor at the University of Leicester in England.
The potential range of birds covers thousands of kilometers of open space along the Pacific coast and across the oceans, but Guiri said the animals still prefer certain places to hunt and feed.
“This type of eating behavior has only recently been discovered in birds today,” he said in an interview. “But we have evidence of what has been happening for thousands of years. The same birds enter the same area throughout their lives. “
Researchers have analyzed these eating patterns using chemical fingerprints or isotopic compositions preserved in albatross bones found through archeological excavations and museum samples, according to a study published this month in the open access journal Communications Biology.
One of the places where researchers have collected ancient bone samples is the village of Mowachaht Nuu-chah-nulth on Nutka Island off the west coast of Vancouver Island, dating back to 2300 BC. The study compares samples found on Vancouver Island with those in the United States, Russia and Japan.
Scientists have been able to connect different dots with chemical fingerprints to put together a puzzle of the migration and feeding pattern of the short-tailed albatross for 4,250 years, Guiri said.
By mapping biological markers against known isotope baselines in the range of the species – which was thousands and thousands of kilometers each year of migration – the researchers were able to build a picture of birds’ migratory and forage behavior for hundreds of generations, he said. .
The behavior of birds in search of food gives researchers an idea of their vulnerability, he said.
The short-tailed albatross was nearly wiped out by its feathers between the 1880s and 1930s, leaving no functioning breeding colonies in the North Pacific, from Japan to Russia, Vancouver Island south to California, the study said.
Known for their pink beaks, the wingspan of the albatross can exceed two meters. Their white and gray feathers fade to yellow on their heads.
After numbering in the millions, seabirds are rebuilding their populations, but remain at less than one percent of their pre-collapse levels. The birds are classified as endangered by the Committee on the Status of Endangered Wildlife in Canada.
“As population growth continues, understanding the factors that determine how and where short-tailed albatrosses choose and divide their time between specific feeding areas may be key to developing effective conservation approaches,” the study said.
Guiri said the birds would have “good reasons” to return to the same places to find food. He said it was not clear at the time what the birds were eating, but they knew the squid had been on their diet.
“They will be particularly rich in hotspots. This is especially true where there is uplift and strong winds, so there is a lot of nutrient-rich water, and this is important for the types of food they are looking for. “
That behavior could return when the population recovers, he said.
“The fact that this seems to have been happening to such an extent for so long makes you wonder if there is something more fundamental.”
What surprised him the most, Guiri said, was the constant path and pattern.
“Only the enormous distance they travel thousands of kilometers to the same areas,” he said. “The fact that one species travels great distances and this has been happening generation after generation for thousands of years. It’s just a remarkable degree of consistency. “
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