Most northern fur seals breed on islands in the Bering Sea during the summer and embark on an eight-month-long journey to the North Pacific Ocean to forage for food in November and December of each year. For unexplained reasons, seal births have been declining there since the late 1970s, prompting increased research into the animals’ behavior. Researchers found many pups die during their initial migration from the Bering Sea to the North Pacific Ocean, but the rate at which this happens varies from year to year – and scientists are unsure why.
New research comparing the movements of individual seal pups during their migration with reconstructions of ocean surface winds shows that as wind speed increases, pups increasingly move downwind and to the right. The preliminary findings suggest surface winds could influence an individual pup’s displacement by hundreds of kilometers during their first winter migration.
It is unclear whether being blown downwind is helpful or harmful to the seal pups, but the results offer a new insight into environmental effects on seal survival, according to the researchers.
Read more at American Geophysical Union
Image: Many northern fur seal pups die on their initial migration from the Bering Sea to the North Pacific Ocean, but researchers are unsure why. (Credit: Jeremy Sterling)