Walrus feed chiefly on bivalves, but also eat some shrimp. All of these groups are the Secondary carnivores of the Arctic. These predators eat a variety of organisms from lower levels of the food web. Baleen whales sometimes eat them when chasing schools of fish, and often engulf them incidentally when feeding on zooplankton . Small and large toothed whales and seals hunt them actively.
Some birds become prey of certain mammals, primarily the Arctic Fox.
Some whales consume birds that are on or just above the water surface, usually in the course of feeding on zooplankton. Occasionally these bears also kill Beluga Whales, particularly when they are stranded on shoals at low tide or in very shallow water. Ice Edges and the Ecology Animals tend to be abundant in open water near the ice edge and this is generally the most active biological area in the Arctic. The bottom of the pack ice is covered with single-celled algae . These algae are eaten by a variety of small crustaceans , which in turn are consumed by a wide variety of invertebrates , fish, birds, and mammals.