Phocids

Phocids, commonly known as earless seals, are a family of pinnipeds (Phocidae) that includes many species adapted to life in cold and temperate seas. They differ from the fur seals and sea lions (otariids) and the walrus (odobenids) in several key ways: phocids lack external ear flaps, their hind limbs cannot be rotated forward under the body, and they swim primarily with their hind flippers while on land they move awkwardly compared with otariids.

The family comprises roughly 15 to 25 species organized into several genera and is widespread in Arctic, Antarctic, and temperate waters. Well-known examples include the harbor seal (Phoca vitulina), gray seal (Halichoerus grypus), harp seal (Pagophilus groenlandicus), ringed seal (Pusa hispida), bearded seal (Erignathus barbatus), Weddell seal (Leptonychotes weddellii), leopard seal (Hydrurga leptonyx), and crabeater seal (Lobodon carcinophaga). Monk seals (Monachus spp.) and elephant seals (Mirounga spp.) are also phocids. The Mediterranean monk seal and the Hawaiian monk seal are among the most threatened, while elephant seals are among the largest seals.

Ecology and behavior vary by species but share some traits. Phocids are predominantly aquatic, feeding on fish, squid, crustaceans, and other marine prey. They are strong divers, often reaching substantial depths and durations. Reproduction typically occurs on shore or ice, with females nursing pups for a period before weaning. In many species, males establish territories or engage in displays during the breeding season, and sexual dimorphism is common.

Conservation concerns for phocids include habitat loss, climate change, pollution, and bycatch. Several species are listed as endangered or threatened, and ongoing protection and monitoring are important for their persistence.