For some years now, the plight of the polar bear has looked pretty grim. As climate change continues to accelerate Arctic ice melting, the seasons where they must stay on land, instead of being able to hunt for seals on ice floes, has seemed to doom the species. Some studies have predicted mass starvation by 2068. But according to a new study by researchers at the American Museum of Natural History, extended stays on land might not be so bad for polar bears after all.
Earlier studies have generally assumed that polar bears aren’t really eating anything other than the seals that would under normally make up most of their diets. Severely reduced access to seals would mean too few calories, which would result in starvation. However, as far back as the earliest recorded observations of polar bears, they’ve been eating various other foods while on land. Polar bears have been recording eating snow geese, their eggs, caribou and even some plants.
According to the new study, those other food sources, specifically caribou and snow geese eggs, should be able to provide enough calories for polar bears to survive. It doesn’t even seem like they’ll be short on those calories, especially because the way they’ve been observed acquiring these food shortages are pretty similar to their normal hunting methods.
Caribou are about the same size as seals, and provide a roughly similar calorie count. What really helps is the fact that polar bears have been observed using much the same ambush techniques they use while hunting seals, which means they have about the same calorie expenditure for the same intake. Meanwhile, snow goose eggs require very little effort to come by, meaning even less energy expenditure for the intake.
As long as caribou keep passing through Western Hudson Bay, and snow goose egg predation doesn’t ramp up too much, the bears should be able to survive without taxing the existing ecosystem. Not a perfect solution to melting Arctic ice, but at least things look better for the polar bears.