The icy waters of Antarctica are home to millions of seals representing several species. Most of them belong to the streamlined and blubber-rich Phocidae family, also known as true or earless seals. Though they are hunted by killer whales in the water, Antarctic seals do not have any natural predators above water. They can be seen hauled out on beaches and sometimes even in the snow far from water. They are often observed reposing placidly on land-fast ice and drifting ice floes. Seals found in Antarctica today are tame and trusting of people and boats. Witnessing this great abundance of docile seals is one of the highlights of an Antarctic expedition cruise. Here are a few seal species frequently encountered on a cruise to the Antarctic Peninsula.
The crabeater seal (Lobodon carcinophaga) is an Antarctic specialist and the most numerous seal in the world. They are primarily seen on ice floes, often in small groups. They can be identified by their slender bodies with brown to light yellow coats, often bearing the scars from attacks by leopard seals or killer whales. Adults can reach 7.5 feet (2.35 m) in length and weigh up to 500 pounds (225 kg). Despite their common name, they do not eat crabs. They feed mostly on krill, to which their teeth are highly adapted. Red stains on the ice around resting seals are evidence of their diet. They hunt mostly at night, leaving them plenty of time during the day to lounge around and pose for photographs.
The Weddell seal (Leptonychotes weddellii) was discovered by James Weddell, a British sealing captain. It has the southernmost distribution of any mammal. Weddell seals are generally quite fat with adorable cat-like faces. They have gray or brown coats with dark and light patches all over. Out of water, they have a characteristic habit of laying on their sides with their bellies exposed. Adults can attain weights up to 1,200 pounds (550 kg) on a diet of large fish, which they catch on dives up to 1,600 feet (500 m) deep. They favor coastal areas where they maintain breathing holes in land-fast ice up to 7 feet (2 m) thick. But, unlike Arctic ringed seals who use their claws, Weddell seals use their teeth to scrap away ice accumulating in their holes. This is thought to decrease their life span. Weddell seals are extremely vocal and produce a vast repertoire of sounds including whistles, tweets, buzzes, chirps and growls. Occasionally they can be heard singing on land while apparently dreaming, much to the amusement of cruise passengers.
The leopard seal (Hydrurga leptonyx) is easily recognized by its dark, variably spotted pelage, sleek muscular body, large reptilian head, and broad mouth with long canine teeth. Adults can reach 11.5 feet (3.5 m) in length and weigh up to 1,320 pounds (600 kg). Leopard seals are one of Antarctica’s top predators. They eat everything from tiny krill to young elephant seals. Individuals can often be seen around penguin colonies, where they hunt adult penguins as well as fledglings. The leopard seal’s habit of skinning a penguin by thrashing it violently against the surface of the water is a gruesome spectacle not to be forgotten. Though sometimes acting aggressively around boats, leopard seals are not known to attack people. Kayakers and Zodiac cruisers are often treated to amazing close encounters with these inquisitive and supremely graceful seals.
Along with the Ross seal (Ommatophoca rossii), which can also be found around the Antarctic Peninsula, the seals mentioned above belong to the true seal tribe known as the lobodontine (”lobe-toothed”) seals. Southern elephant seals (Mirounga leonina) are also present in the