Birds fly 16,000 kilometers without cause

Most migratory birds travel long distances from north to south and vice versa to spend heavy winters in warmer climates. Some birds travel from east to west in search of more food.

But Brachyramphus marmoratus is unique in its kind. It crosses the entire Pacific ocean, and the climate does not change significantly throughout the whole of the Pacific. Some birds breed in Canada and then spend the winter in Japan, China or Korea. This is the only feathered species that goes all the way across the Pacific Ocean.

"This is a great mystery," says Tony Gaston of the National Center for Wildlife Research. "It's a long way to go, and there's no clear reason why."

To investigate the migration of these interesting birds, Guston and his colleagues used geolocators. The results showed that birds moved from Canada to Japan from July to November. "I'm not familiar with another species of birds that passes such a huge distance from east to west. Especially provided climatic conditions and food stocks are similar in both places. "

It is even more strange - in February, the birds take the opposite path, this time arriving in Canada for only a month. That is, they had to pass 270 kilometers a day, equivalent to at least 4-5 hours of continuous flying. Guston and his colleagues do not know why one trip is so shorter than the other, but the basic theory is related to the loss of the plumage that slows down the speed of flight.

Genetic evidence suggests that Brachyramphus marmoratus comes from Asia and settled in North America very soon. It is possible for the birds to re-iterate mechanically the way they colonized the North American continent. "There is no other satisfactory explanation," Guston concluded.

images source: pixabay