© Photo copyright Katie Florko.
7/12/2017 8:47:38 AM
Why Arctic Sea Ice Matters: Ringed Seals
Ringed seals live across the circumpolar Arctic. They are an ice-dependent species. During the winter and spring, they create breathing holes in the ice, maintaining multiple openings to help avoid polar bear predation.
While sea ice plays an important role in the ringed seal’s life history, the most critical time period is possibly late winter and early spring. During the winter, when the snow falls and snowdrifts form, a pregnant female ringed seal will dig out a birth lair in a snowdrift above one of their breathing holes.
When spring comes around, ringed seals give birth to their pups in these lairs, which provide protection from polar bear predation and help keep the young seals warm. The pups remain in the lair for about six weeks while they gain body fat from their mom’s rich milk. This is a critical part of the ringed seal’s life history, and also a key time of year for polar bears.
Blubber is an essential component of a polar bear’s diet. Newly weaned seal pups are naïve to the danger of predators. Their bodies are approximately 50% fat, providing an excellent source of blubber for polar bears. Polar bears take advantage of this time, feasting on the ringed seal pups and storing the energy for times when less prey is available.
But without sea ice and snow, ringed seals are unable to build effective birth lairs for their pups.
Polar bears do not simply rely on sea ice as a physical platform for traveling, hunting, and mating, but rather sea ice is critical for ringed seals—a vital part of the Arctic marine food web and the polar bear's main prey—to reproduce and survive.