What important Antarctic animal answers to the name fin-feet? Seals, so named because of their large fin-like flippers. Their official name is pinniped, which also means “winged feet.”
There are three types or families of seals:
- Eared seals are fur seals and sea lions, who rarely live in sub-polar zones.
- Earless seals, also called true or hair seals, include five species in Antarctica – Weddell, Crabeater, Elephant, Leopard, and Ross seals.
- Walruses are more closely related to eared seals, and they live in the Arctic.
Fur Seals Have Ears
Southern Fur seals – the only eared seal in the Antarctic – have visible earflaps and short broad snouts. Adult males are medium to dark brown and weigh up to 200 kg (440 lb). Fur seals are smaller than Antarctic true seals, and males are larger than females. Females can be up to 4 times smaller than males, and they are greyer with a lighter underside. Sometimes you’ll even see a blonde in the bunch.
Fur seals are known primarily for their thick fur coats, which are waterproof and mostly windproof. This coat has two layers – a coarse outer layer of guard hairs and a velvety underfur. Unfortunately, their fancy fur coats were nearly their undoing when Antarctic fur seals were hunted to near extinction for their pelts. They made an amazing comeback, and now 95% of the world’s fur seal population lives on South Georgia Island.
Fur seals are also called “walking” seals. Though they don’t stand as upright as penguins, these seals are well adapted to strolling across on the land and ice on their muscular tail and flippers. They bring their rear flippers forward and under them and put weight on their front flippers to create a walking or running motion.
Eared seals are less adapted to a watery lifestyle than earless seals, but not by much. Like true seals, fur seals also love to play and dine with their friends in the ocean. Fur seals have their coats to keep them warm so they have less blubber than true seals. That makes them especially agile in the water.
Eared seals live about 15-25 years, with females probably outliving males because of the stressful competition between males for breeding rights.
True Seals Are Earless
Not really. True, or earless, seals do have ears. They just don’t have visible earflaps. True seals are also called hair seals – again, they have fur, but it’s not the lovely thick coat found on fur seals.
True seals are better designed for water than for land. They are sometimes called “crawling” seals because most are built for efficiency in the water vs speed and agility. Some strictly live in the ocean and on the ice and don’t bother with terra-firma at all. They depend more on their well-developed blubber than on their fur to keep warm.
Not all Antarctic true seals are truly alike. They range greatly in size. The Elephant seal is the largest at over 5 meters (15 ft) long and over 2 tons (8000 lbs) for males. The Ross seal is the smallest at less than half the size of an Elephant seal. Most males are bigger than the females, except for Crabeaters and Leopard seals.
Each type of true seal looks a little different, which helps us non-pinnipeds identify them. Weddell seals are grayish with lighter streaks on their underbelly, and they have beautiful, sensitive eyes. Ross seals have distinctive markings on their throat and heads. Of course, Elephants are huge with a lot of fat and a giant proboscis. Leopard seals have snake-like bodies with large toothy mouths – the better to eat you with. Crabeaters are the most prolific of the species. More than half the seals in the world are Crabeaters.
Earless seals have different habits and preferences from each other, and they live and breed in slightly different places.
Weddells live the furthest south of any other mammal and they seem to stay on inshore fast ice. They create holes in the ice, where they enter and exit the water and pop up for a breath of fresh air. Weddells maintain their breathing holes by sawing and grinding the ice with their teeth. This practice creates serious dental issues that might cut their lifespan in half – Weddells live around 18 years, while Crabeaters live into their 30’s.
Ross and Leopard seals usually move with the flow of the ice. Ross seals in particular hang out deep in the ice and rarely haul out on land.
Crabeaters are not land lovers either. They prefer to haul out onto ice, where they can just slide around. These guys have a huge play area, considering the pack ice expands from 4 million square km (1-1/2 million sq miles) in the summer to 22 million square km (8-1/2 million sq miles) in the winter.
Southern Elephant seals live both north and south of the polar front around Antarctica, and they make a habit of crowding side by side in noisy, smelly piles on beaches. They breed on the surrounding islands as well as the Argentina and Patagonia coasts.
Seal Songs And Conversations
Like all animals, seals have their own language. Both eared and earless seals sing and make various other sounds above and under
water, including barking, growling, moaning, and even belching!
Some species make a lot of noise while others are relatively quiet. How talkative a seal is can depend on its environment. More communal s
pecies living in colonies talk more than solitary species living further apart. A seal probably won’t talk much to itself, but get it on a beach with a lot of its buddies… a few fish later… you know how it goes.
Fur seals should be called “barking” seals, since that’s how they communicate. Earless (true) seals don’t typically bark, and instead they do more grunting and slapping the water.
Elephant seals bellow and roar, particularly the males. Their big noses become echo chambers that emphasize their statements.
Weddell seals are known for being particularly talkative under water, communicating with a series of whistles, buzzes, chirps, tweets, growls that seem complicated to the average person. Males can be heard up to 30 km (20 miles) away.
[TRIP TRIVIA: Weddell Seals were named after the British commander Sir James Weddell. Ironically, he led sealing expeditions in the Weddell Sea, which was also named for him.]
What’s On The Menu?
What do seals eat? All of them are carnivores. The details depend on the species, but mostly fish, krill, invertebrates, squid, penguins, and other sea creatures. The bigger the mouth on the species, the bigger its preferred prey.
Leopard seals have the biggest mouths and they’re the most gruesome predators of the bunch. They nab penguins and flip them inside out to access the meat. Discarded penguin skins indicate a leopard seal is in the neighborhood. Even other seals need to look out for these hungry relatives.
Don’t be confused by a name: Crabeater seals don’t eat crabs. Crabeaters nearly exclusively eat krill.