Polar bears forced to change diet due to retreating ice

Polar bears are having to shift their diet from eating seals and other marine animals to plants and land animals, largely due to climate change.

Three different studies published last year suggest that the warming Arctic is forcing polar bears in western Hudson Bay to forage through vegetation, including mushrooms and berries, replacing their regular diet of seal pups with snow geese and caribou. The consumption of seal pups and marine animals during the spring months is essential for the bears as this is when they gain their fat reserves.

Polar bears are known for standing near breaks in the ice and waiting for seals and other marine animals to surface before pouncing on them. As sea ice is melting earlier and reforming later during the course of a year, these hunting patterns are increasingly difficult.

Foraging local vegetation means the bears are not moving beyond their habitats, suggesting they are keeping energy expenditure at a minimum. Researchers also believe this foraging behavior comes from a shared genetic heritage with brown bears.

“For polar bear populations to persist, changes in their foraging will need to keep pace with climate-induced reduction of sea ice from which the bears typically hunt seals,” said Linda Gormezano, researcher at the American Museum of Natural History.

[American Museum of Natural History]