Polar bears turn to Goose eggs to survive

Polar bears may be turning to snow goose eggs to help them survive as Arctic sea ice melts due to global warming, scientists say.

Polar bears typically hunt seals out at sea, returning to land when springtime temperatures melt the ice floes the bears use as rest stops. But climate change has been causing sea ice to melt earlier each year, forcing polar bears to come ashore sooner.

In a previous study, biologist Robert Rockwell and his colleague Linda Gormezano documented polar bears in Canada's Hudson Bay area returning to land about two weeks earlier than they'd done in the past, near the end of June instead of the middle of July. This early arrival brings the bears back to shore around the same time that nesting snow geese are incubating their eggs in Hudson Bay.

Snow goose eggs are more often food for skuas and Arctic foxes. But polar bears are famous for their voracious appetites. One polar bear reportedly went on a 'goose egg-fest,' Rockwell said, devouring more than 800 eggs in four days.

Accounts like this have caused some scientists to worry that hungry polar bears might severely reduce or wipe out nesting snow goose populations.

But in new research, recently published online in the journal Oikos, Rockwell and his team show that the currently plentiful snow goose population is in no danger from the bears. In fact, the eggs might provide a valuable backup food source as polar bears are forced to end their seal hunts early.

For one thing, a snow goose egg is about twice the size of a chicken egg, but it is much more nutritious, said Rockwell, a research associate at the American Museum of Natural History and a professor at the City University of New York.

National Geographic News