There are many species of seals living in the tundra biome, including harp, grey, Weddell, elephant and ribbon seals. Seals are great swimmers that dive deep into arctic seas to hunt for fish, although they gather on land for mating, socialising and birthing pups. With thick fat deposits and watertight coats, seals are well-adapted to their cold environments.
Seals are mammals, even though they live and hunt in the sea. Mammals breathe air, birth live young, feed their young with milk, have fur and are warm blooded. Other sea mammals include orcas, sea lions, whales, dolphins and manatees.
Born on Land or Ice
Most seal species are born on land or ice, even though they spend most of their lives living and hunting in the sea. Many seal populations gather on rocky tundra shores for birthing pups, moulting and breeding. Some species, such as the Weddell and ringed seals, gather on thick ice deposits in the middle of the cold seas. The Weddell seal spends most of its time under the ice, emerging only to breath and birth pups.
Seals can hold their breath for a long time underwater and dive very deep by letting air out of their lungs. The Weddell seal lives in Antarctica and can hold its breath for up to an hour. Many species of seal also blow air bubbles under the ice to breath between dives. Staying under the ice helps seals avoid predators, such as polar bears.
Because seals that live in the tundra must survive very cold conditions, their bodies have adapted in many ways. Arctic seals have thick layers of fat called blubber that protects their internal organs from cold. Other species, such as the harp and bearded seals, grow very thick coats that help keep their body temperatures high.
In a process called moulting, baby seals lose their thick fur quickly to reveal a sleek adult coat. Most seal species moult in the warmer months, and some seals that live in the tundra migrate to warmer seas to moult.
Named for Coat Markings
Harp, ribbon, ringed, leopard and spotted seals are named for the different markings they have on their coats. After moulting, harp seals usually have a distinctive black harp pattern. Ribbon seals and ringed seals have swooping lighter marks on their dark coats. Leopard seals have dark spots on their tan or brown coats, and spotted seals have light grey or white spots on dark grey or black coats.
Seals and Sea Lions
Seals are different from sea lions in specific ways. Sea lions can walk on their back flippers, but seals pull themselves over land using only their front flippers. Sea lions also have flaps that cover their ears, but seals' ears are flat to their head without flaps. Having flat ears enables seals to swim faster.