ANCHORAGE, Alaska (AP) - The main prey of polar bears has been declared a threatened species because of diminishing sea ice due to climate warming. The National Marine Fisheries Service on Friday declared ringed seals as a threatened species, joining polar bears on the list.
The agency also placed a second ice-dependent seal, bearded seals, on the list. Ringed seals are the only seals that thrive under completely ice-covered Arctic waters. They use stout claws to dig and maintain breathing holes. Females give birth in snow lairs to pups that are susceptible to freezing until they grow a blubber layer. Bearded seals give birth and rear pups on drifting pack ice. Sea ice this year reached record low levels.