Grim photo captures polar bear mom and cubs resting in mud in summer heat

A mother polar bear and her three cubs pause in the summer heat.

In "Family Rest," Christopher Paetkau captured a polar bear mom and her cubs napping in Canada's summer heat. (Image credit: Christopher Paetkau / Wildlife Photographer of the Year)

A bleak photograph shows a mother polar bear and her three cubs resting on bare ground and moss, their coats brown with mud.

The image is on the shortlist for this year's Wildlife Photographer of the Year Nuveen People's Choice Award — a contest in which members of the public vote for their favorite among 24 images that have been selected by the Natural History Museum, London, and a panel of photography and wildlife experts.

The touching new photograph is a reminder that global warming endangers polar bears by shrinking their sea ice habitat, forcing them to find new sources of food elsewhere. Unlike other bears, polar bears (Ursus maritimus) do not hibernate. Previously, most polar bears spent the entire year on the ice hunting their favorite prey of ringed seals (Pusa hispida) and bearded seals (Erignathus barbatus). But with sea ice declining each year, polar bears now have to seek out more land-based prey, such as reindeer.

Another image of a polar bear is also shortlisted for this year's People's Choice Award. It captures a cub during a hunting trip on the Norwegian archipelago of Svalbard that ended in tragedy when the baby bear and its mother approached a human settlement. The mother bear was found dead shortly after, and police officers shot the cub because it seemed aggressive.

Voting for the Nuveen People's Choice Award is now open online until March 18 for anyone to select the winner of the people's choice award.

The winning image and four runners-up will be announced March 25.