elephant seal or sea elephant, a true seal of the genus Mirounga. It is the largest of the fin-footed mammals, or pinnipeds, exceeding the walrus in size. There is a northern species, Mirounga angustirostris, along the Pacific coast, and a larger southern species, M. leonina, that breeds on sub-Antarctic islands. Males commonly reach a length of 18 ft (5.5 m) and a weight of 5,000 lb (2,270 kg); the female may measure 10 ft (3 m). A hollow, flabby snout about 15–18 in. (38–45 cm) long on the male gives these seals their name. During the 3-month breeding season the largest bulls stake out territories and try to attract and hold as many females as possible. When a bull is sexually excited or angry it snorts air from the proboscis into the throat, producing sounds heard miles away. Bulls do not eat during breeding, but females without pups feed on squid, fish, crabs, and other organisms that compose their main diet. These earless seals are graceful in water, diving to 2,275 ft (700 m) for food. Seal hunters, who extracted oil from blubber, pushed the northern species to the edge of extinction in the 19th cent. In 1911 the Mexican government extended protection to the single remaining M. angustirostris colony on Guadalupe Island off Baja California; the United States eventually followed suit. By the early 1990s an estimated 60,000 animals were found on island rookeries off Baja and central California. Elephant seals are classified in the phylum Chordata, subphylum Vertebrata, class Mammalia, order Carnivora, suborder Pinnipedia, family Phocidae.

See W. N. Bonner, Seals and Man (1982); B. LeBeouf, Elephant Seals (1985); F. Trillmich, ed., Pinnipeds and El Niño (1991).