The Antarctic fur seal is an eared seal that breeds mainly on sub-Antarctic islands and hunts in the cold Southern Ocean. Thick underfur once made it a target for commercial hunters, but protection allowed an extraordinary recovery during the twentieth century. The story has taken a darker turn: warming seas and reduced access to krill have driven a major modern decline, and the IUCN listed the species as Endangered in 2026.

Arctic foxes are small, tough foxes that live in some of the coldest places on Earth. They have thick fur, furry feet, short ears, and clever food-finding skills that help them survive in the icy Arctic.

The Arctic hare is a large hare built for the treeless tundra of northern Canada and Greenland. Thick fur, short ears, a compact body, and enormous furry feet help it survive bitter wind and snow. Far-northern hares stay white for most or all of the year, while some southern populations develop gray-brown summer coats that blend with exposed rock and vegetation.

Beluga whales are small white whales that live in cold Arctic and subarctic waters. They are social, vocal, and famous for their rounded melon heads, flexible necks, and many whistles, clicks, chirps, and squeals.

Bowhead whales are huge Arctic baleen whales with dark bodies, massive bow-shaped heads, thick blubber, and giant mouths. They live in icy northern waters and can survive for an extremely long time.

The caribou, Rangifer tarandus, is a cold-adapted deer of North America’s Arctic, subarctic, boreal forests, mountains, and tundra. It is the same species that people call reindeer in Eurasia, although the word reindeer is also widely used for domesticated and semi-domesticated animals. Caribou populations differ greatly: some live in forests or mountains, while enormous tundra herds make long seasonal journeys between winter ranges and spring calving grounds.

The colossal squid, Mesonychoteuthis hamiltoni, is a massive deep-sea cephalopod found only in the Southern Ocean around Antarctica. It is shorter than the longest giant squid but has a broader, heavier body and is the heaviest known invertebrate. Adults live in freezing water at depths of roughly 1,000 metres or more, where direct observation is extraordinarily difficult. Much of what scientists know comes from rare specimens and beaks recovered from sperm-whale stomachs.

Emperor penguins are the largest penguins in the world. They live in Antarctica, survive freezing weather, dive deep for food, and gather in huddles to stay warm on icy breeding grounds.

The Harp Seal, Pagophilus groenlandicus, is a true seal of the Arctic and North Atlantic oceans. Adults have pale silver-gray bodies, dark faces, and a black harp-shaped or saddle-like marking across the back and sides. They migrate between feeding seas and drifting pack-ice breeding grounds. Three main populations or stocks breed in the Northwest Atlantic, Greenland Sea, and White Sea or Barents Sea. Females give birth to one pup on the ice and nurse it for less than two weeks before returning to sea.

The Leopard Seal, Hydrurga leptonyx, is a large solitary true seal of the Antarctic pack ice and Southern Ocean. It has a long muscular body, powerful front flippers, a broad reptile-like head, enormous jaws, and dark spots across a pale underside. Females are generally larger than males. Leopard Seals are unusual predators because the same mouth can seize penguins, fish, squid, and young seals while interlocking back teeth strain tiny krill from seawater. The species is currently assessed as Least Concern, but its abundance is difficult to measure across moving pack ice.

Musk oxen are shaggy Arctic mammals with thick coats, curved horns, short legs, and strong bodies. They live on cold tundra in places such as Canada, Greenland, and Alaska, where herds help each other survive.

Narwhals are small Arctic whales famous for their long spiral tusks. They are sometimes called unicorns of the sea, but the tusk is not a horn. It is actually a special tooth.

Polar bears are huge Arctic bears built for ice, snow, cold water, and seal hunting. They have thick fur, strong paws, a great sense of smell, and a close connection to sea ice.

Reindeer are members of the deer family that live in cold northern places. They are also called caribou in North America and are known for antlers, wide hooves, thick fur, and traveling in herds across snowy lands.

The ringed seal, Pusa hispida, is a small true seal adapted to icy northern waters. Pale rings and spots pattern its darker back, while strong front claws keep breathing holes open in sea ice. Most ringed seals live around the Arctic Ocean, but distinct subspecies also inhabit the Baltic Sea and the freshwater lakes Ladoga and Saimaa. Snow, ice, and access to water shape nearly every part of their lives.

Snowy owls are large white owls with bright yellow eyes, round heads, thick feathers, and powerful wings. They live in Arctic tundra and can wander far south when food is scarce.

The southern elephant seal is the largest seal and one of Earth’s most extreme diving mammals. It breeds and molts on subantarctic and southern coasts but spends most of its life roaming the cold Southern Ocean for fish and squid. An adult male can weigh several times as much as a female and develops the inflatable trunk-like nose that gives elephant seals their name.

Walruses are huge Arctic marine mammals with long tusks, thick blubber, wrinkly skin, stiff whiskers, and flippers. They spend time in cold seas and haul out on ice or beaches to rest.

The Weddell Seal, Leptonychotes weddellii, is a large true seal that lives around Antarctica, especially beside stable coastal fast ice. It is the only living species in its genus and is famous for maintaining breathing holes with its teeth, making eerie underwater calls, and diving beneath sea ice for fish and other prey. Weddell Seals breed farther south than any other mammal, but they still need open cracks or holes because they breathe air. Their global IUCN category is Least Concern, while climate-driven changes to sea ice and food webs remain important long-term concerns.