Weddell Seal

Weddell Seal Facts

LATIN NAME Leptonychotes weddellii.

LENGTH 2.5–3.5 m (8.2–11.5 ft) long.

WEIGHT Adults commonly weigh about 400–500 kg (880–1,100 lb).

LIFETIME About 20 years, although some individuals live beyond 30. The long-running Erebus Bay study has documented a female still producing pups at age 31.

PHYSICAL TRAITS Their coat is mottled with large darker and lighter patches, and they have upturned, “smiling” mouths.

BEHAVIOR Deep dives may reach some 700 m (2,300 ft), and exceptional dives go farther: recent research reports depths beyond 900 m (2,950 ft) and durations up to 96 minutes. These are extremes, not typical dives. Weddell seals avoid blizzards by staying underwater and breathing through holes in the ice. They are very placid animals when resting on the ice, but should be observed without disturbing them.

Found in the Antarctic, the Weddell seal’s complex descending sweeps and chirping calls are associated with breeding and social interactions. Both males and females vocalize; males use calls while defending underwater territories during breeding season. Signals are complex in frequency, amplitude, and time domain. Not enough is known to fully explain what accounts for the complexity. A 2020 study added nine ultrasonic call types, recorded throughout the year, above the range of human hearing; their functions remain uncertain.

HABITAT On, under, and around the Antarctic sea ice, especially coastal fast ice attached to the shore.

LOCATIONS Antarctica and surrounding coastal waters.

FOOD Fish, squid, octopus, and bottom-feeding prawns and other crustaceans. Diet varies with location and season.

PREDATORS At sea or on pack ice, they become prey for killer whales and leopard seals. Young seals are particularly vulnerable. Fast ice and the under-ice environment offer relative protection.