Reindeer
Reindeer live on Arctic tundra, mountain tundra and northern forests. Large members of the deer family that Reindeer live on lichens in the winter they are very well adapted for the harsh Arctic tundra where they migrate great distances each year. Reindeer have unique hairs which trap air providing them with excellent insulation. These hairs also help keep them buoyant in the water. They are very strong swimmers and can move across wide rushing rivers and even the frozen ice of the Arctic Ocean! They have large, concave hoofs that spread widely to support them in deep snow and soft tundra, and can be used as 'shovels' to dig for their food 'lichen.' The hooves also function well as paddles when they swim. 

Learn more about reindeer

Brown Bear
Brown bears live throughout the Arctic. "Brown" and "grizzly" bears are now considered to be in the same family. Weighing up to 290-1,500 pounds (130-700 kg), the larger brown bears tie with the Polar bear as the largest land carnivores. In winter when food is unavailable or scarce, most brown bears enter dens and sleep through winter. In Chukotka where the winters are long and harsh, brown bears may spend as much as 6 to 7 months asleep in their dens. 

Arctic Tern
The Arctic tern is one of the greatest travelers in the animal kingdom. Living in the Arctic over the summer, it migrates (flies) to its winter spots in Antarctica - a journey of at least 16,000 km! This tern is about 35-43 cm in length, smaller than a crow. Because Arctic terns divide their time between the two north and the south pole, living to enjoy the summer midnight sun of each place, these birds see more hours of daylight than any other animal! 

Polar Bear
Polar bears spend much of their life on the sea ice. Their coats are made up of water repellent guard hairs combined with a dense underfur that covers to the bottom of their feet. Polar bears have short, thickly furred snouts and ears that minimize heat loss to the environment. They have black skin, black tongue and black paws, but if you take each individual hair it is actually clear and it is hollow. The black skin increases the air temperature close to its skin when the sun shines on it and this air is then trapped in its coat of hollow hairs. Polar bears also have an extreme sense of smell. Polar bears can smell a seal up to one mile away or under three feet of ice. 

Moose
Moose are the largest member of the deer family in the world. Moose are long-legged and thick-bodied, adaptations that enable them to move about through deep snow and wet lands and to carry sufficient fat stores. Their thick, hollow hair is fatter at the tip than at the base. The shape helps trap an efficient insulating layer of air next to their bodies. 

Raven
The raven lives from the Arctic islands to northern Africa, and it is one of the few birds that can live and survive year-round in the Arctic. Ravens eat almost anything. When more food than they can eat at the time, ravens cache, or hide, their food and retrieve it later. Standing on snow and ice is chilly. Ravens have developed knobbly feet to reduce their contact with the cold ground. When these birds land, the small bumps on    the soles of each foot touch the ground first, keeping most of the foot off the cold snow. This protects the feet and reduces the amount of body heat lost to the cold surface. 

Wolf
Arctic wolves generally appear white from a distance, but actually have grey, black, or reddish flecks in their coats. Their extremely dense underfur insulates them against harsh Arctic winters.  Wolves hunt and live most of their lives in a pack with other wolves in their territory. Though wolf   packs tend to remain within a home range of 200 to 600 square miles, they will abandon their range and travel longer distances if necessary to follow migrating herds of animals such as reindeer or caribou. 

Wolverine
Wolverines are a relative of the mink and weasel. Wolverines have tremendous physical endurance - they are very strong. They may travel up to 40 miles each day in search of food, a necessity for an animal that does not hibernate. Even though they are not very large (an adult male averages about 14.5 kg or 32 pounds), wolverines are capable of bringing down some of Arctic's largest hoofed mammals. It can kill moose and reindeer weighing up to 500 kg. During the summer, wolverines eat a wide variety of foods: lemmings, voles, ground squirrels, eggs, carrion, berries, and roots 

Arctic Fox
The Arctic fox has a gray, or blue coat in the summer and a thick, warm white coat in the winter. They molt twice each year with the changing of the seasons. The foot pads of an Arctic fox are also densely furred so that they can travel on the snow and ice hunting for prey. The arctic fox feeds on lemmings, voles, squirrels, birds, bird eggs, berries, fish and carrion. In the winter the fox will follow polar bears hoping to eat the bear's leftovers. The Arctic fox has to be very sly or it will become the polar bear's dinner! In the winter they dig through the snow to capture lemmings. They have an excellent sense of hearing, which helps pinpoint the location of snow-covered prey. 

Lynx
Lynx inhabit forested terrain and are shy and unobtrusive animals. Lynx have short tails, and usually a tuft of black hair on the tip of the ears. They have a ruff under their neck which has black bars (hard to see) and it looks like a bowtie. They have large paws padded for walking on snow, and long whiskers on the face. The color of the body varies from light brown to grey and is occasionally marked with dark brown spots, especially on the limbs. It feeds on birds and mammals, fish, and often on sheep and goats, but its main prey is the Snowshoe Hare. It is very rare to spot a lynx because they are extremely shy and solitary nature of the animal. 

Snowshoe Hare
Unlike rabbits, snow hares are born fully furred with eyes open and can walk by the time their fur is dry. The hare's summer coat of yellowish to grayish brown is replaced by white pelage in winter. The Arctic hare is active year-round, feeding on Arctic willow, crowberry, meat, and seaweed. The huge feet these animals have act as snowshoes to enable quick escapes on top of the snow. 

Sea Otters
Sea Otters are playful animals that spend almost all their time in the sea. They eat, sleep, and even have their babies in the water. In the daytime sea otters float on their backs eating Abalone, their favorite food. To open the Abalone shell they place a small rock on their chest and smash the shell against it. Sea otters are one of the few mammals, beside humans, that use tools. They will use strands of kelp to tie themselves into the kelp beds for a secure night's sleep. They love to frolic with other otters and seals. Unlike seals and walrus, sea otters have no blubber to keep them warm in the cold arctic waters. Air trapped in their fur keeps them warm and buoyant. Oil spills can damage this fine fur and cause the otter to get very cold and die. That is why volunteers cleaned the sea otters so carefully after the oil spills in Alaska. 

Lemming
Lemmings are small mouse-like animals that live in the tundra. In summer they are brown, but in winter they are all white. Their white coats help them to hide from the snowy owl and other predators who depend upon them for food in winter. They have rounded bodies with long tails, and have teeth for eating seeds, grains, and other plant material, as well as insects. Lemmings make simple burrows in the tundra during the summer and in the winter, they hide from the coldest weather in shallow burrows in the snow. Most of them do not hibernate; but stay active all winter, tunneling through the space that forms between soil and snow in  search of vegetation. Their short appendages (ears, legs, tail) help reduce heat loss, and their fur grows thicker in winter. 

Muskox
Muskox look a lot like bison, but have wool like sheep. They are called omingmak meaning "the animal with skin like a beard," because of the long guard hair that hangs nearly to the ground. Muskox have not changed much since the ice age and are perfectly adapted to live in their harsh Arctic environment. Stocky and with a very short tail, muskox have cloven hooves, all four of which are the same size. Muskox underwool-called qiviut-is considered the softest and warmest in the world. Muskox roam in herds of 10-20 individuals. When they are threatened they form a circle around their young to protect them. Muskox have been known to scoop up wolves with their horns, hurl them into the air and then stomp them under hoof. But muskox are peaceful animals who eat only plants. Their name comes from the musky smell of their urine, which is especially strong in mating season. Muskox usually bear one calf every two years. 

Arctic Ground Squirrel
The Arctic ground squirrel lives throughout the Arctic. Known to the Inuit as siksiks - a descriptive term for their alarm call - ground squirrels are the only Arctic mammals that hibernate deeply, lowering their body temperature close to 0°C, and their heart rate from 300 to 5 beats per minute. Arctic ground squirrels live in colonies, in a system of burrows with several side branches and exits to the surface. They eat a variety of plants, including the leaves, seeds, flowers, and roots, and it is not uncommon for hungry adult males to cannibalize young squirrels. 

Bowhead Whale
The bowhead whale, only live in the north - in Arctic and sub-Arctic waters, close to the edge of the pack ice. It is called a bowhead because of the curve in its upper jar. It is also known "the whale with a moustache," because of the sheets of baleen that hang from its jaw. Baleen are horny plates with fringes that acts like a massive filtration system which the bowhead use to eat with. Bowheads are the longest of any whale - up to 18 m (54 feet) long  and weigh 60 to 100 tons, with a 50 cm (1-2 feet) thick layer of blubber that weighs 30 tons. Instead of tear ducts with water, their tears are grease! 

Ringed Seal
Seals swim in Arctic waters eating fish like arctic cod as well as crustaceans and mollusks. They are great divers and can stay under water for long periods of time without returning to the surface for a breath. Their rear flippers are turned backward. This improves their swimming, but makes it difficult to move around on land because their toes point backwards. Try walking around with your toes pointing backwards!  Instead they prefer sliding around on the ice. Ring seal is the smallest seal there is; adults measure about 5 feet (1.5 m) long and weigh only 110 lbs (50) kg with a thick layer of blubber that keeps them warm. They are brown to bluish black in color with irregular creamy rings. The ringed seal spends most of its time beneath the ice. It digs up through the ice with its strong claws to open breathing holes and must keep pushing it nose through the ice to keep the holes from icing over. 

Walrus
The walrus, is in close family with seals, but has two separate hind legs. Males reach 12 feet (4 m) in length and weigh up to 2500 lbs (1200 kg). Walrus are best known for their tusks which are actually two elongated canine teeth. Their latin name, Odobensus , means "tooth walker", referring to their behavior of dragging themselves along the ice using their tusks. In summer, walrus herds often bask on small islands or ice floes. Then they turn pink as their blood vessels widen out to not overheat.  Walrus are very slow on land because they are so big and clumsy, but in the water they are very fast and strong.  They can dive down 300 feet to retrieve their favorite food, clams, from the sea bottom. A walrus can eat 4,000 clams in one feeding! Air sacs in the walrus' neck allow it to sleep with its head held up in the water. Nursing females use this standing position as they nurse. The pups, born approximately every two years, nurse upside down. 

Tundra Shrew
The Arctic Tundra Shrew is the most brilliantly colored shrew. In winter its black back and brown sides contrast sharply with its grey belly, while in summer its entire coat is a dull brown. It is usually about 3 inches (7 cm) long with a tail little less than an inch (2 cm). They eat insects. Because they are so small (their surface area-to-volume ratio is very high), and they live in such a cold place they need to eat every 3-4 hours. In fact, a typical Arctic shrew will eat  up to three times its body weight in just a day! 

Ptarmigan
Ptarmigan are small chicken-like birds that live in the Arctic year-round. They have grey plumage (feathers that covers a birds body) or brownish with dark stripes in summer, but completely white in winter. In summer, they blend into the tundra plants and look like shadows; in winter, they look like the snowy ground they walk on. The snow makes getting around a challenge for the ptarmigan, which spends most of its time walking around on the surface of the ground, searching for plants to eat. In order to prevent itself from sinking, the ptarmigan grows extra long claws on its toes each winter. These claws help it to get a grip on icy surfaces, and act as snowshoes in softer areas. 

Arctic Cod
The Arctic cod lives all over the Arctic and the furthest north of any other marine fish. It temperatures best below 40° (4°C), and it is one of the few fish that thrives in temperatures below 32° F  (0°C). Antifreeze proteins in its blood are one adaptation responsible for this ability. This fish is very important to the Arctic food web and is the number one food source for narwhals, belugas, ringed seals, and seabirds. The age of an Arctic cod can be determined by counting annual rings of growth in its otoliths, the tiny bones in their inner ear, much like counting the rings of a tree. 

Snowy Owl
Snowy Owls are found only in the Arctic, and are seen most commonly sitting very still on the tundra. Arctic owl, white owl, and snowy owl are all names used to describe this large white predator. In summer, Snowy Owls are brownish with dark spots and stripes.  In winter, they are completely white. The white feathers also provide excellent heat insulation Feathers extend down the snowy owl's legs and cover its toes, providing protection from the cold. Snowy owls eat lemmings and during the spring breeding season, owls will also feed on eggs of waterfowl.. Most owls hunt at night, but these owls are different in that they will hunt during the day - they live in an environment where the sun may not set for up to four months! In summer, they blend in to the tundra colors and look like shadows; in winter, they look like the snow covering the ground. Snowy Owls do not fly south in the winter, but will stay wherever there is food to eat. 

Narwhal
The narwhal is a small whale that reaches a maximum length of 15 feet (5 meter). Adult males have a long, spirally twisted tusk up to 9 feet (3 meter) long, which come through their upper lip and is hollow for most of its length. Narwhals sometimes travel in herds of more than 1000 animals, which are so noisy they can be heard a mile away (several kilometers). Native Arctic peoples have long valued the narwhal and hunted it for its tusk and thick skin, which is traditionally eaten raw as a delicacy.