Scientific Name: Odobenus rosmarus
Walruses are easy to recognize because of their large ivory tusks, bristly mustache and their enormous size. Only the elephant seal is a larger sea mammal. The tusks are really canine teeth and yes, walruses are thought to be descendants of dogs and wolves. The tusks can grow up to 1m in length and they are used to poke holes in the ice, as an anchor to hook onto ice floes while sleeping, and in males for fighting. Walruses live in the ocean and on ice floes, coming to land mainly to breed. Males are about 3m long and can weigh 2000kg (4,500 pounds), while the females are 2.6m long and weigh 800-1,800kg (1760-4000 pounds). Their average lifespan is 50 years. As with sea lions, walrus rear flippers turn and can be for movement onshore. Walruses do not have much fur and look like they are bald. They are deep brown in color as young adults and fade to more cinnamon in color as they age. Their tough skin has many folds and wrinkles and under their throats there is an air sac for keeping them afloat in the ocean while they sleep. Like seals, they have only ear holes and no ear flaps, and their eyes are very small. The Pacific walruses are more well-known and live along the coast of Alaska and Eastern Siberia. Males often gather together on rocks offshore and it is not unusual to find 10,000 or more piled up in one place. Females, however, prefer lounging on the pack ice. Walruses swim about 7km/hr, but reach top speeds of 35km/hr.
The males come ashore for breeding in January and February and eat very little during this time. When the females arrive, the males sing to them and fight over them. Walruses breed in the water. For the first 4-5 months the fertilized egg is in the mother's womb, but is not implanted and this makes them very unusual among marine mammals. The mothers are pregnant for 15-16 months and only give birth every 2-3 years. One baby, called a calf is usually born between April and June, while the walruses are migrating north. Calves are about 110cm long, weigh 60kg, and are born without tusks. The bond between the mother and baby is very strong and the calves nurse for up to 2 years.
Walruses eat many different kinds of sea animals (crabs, shrimp, corals and tube worms) that are found at the bottom of the ocean, but they prefer mollusks (clams). They sometimes crack clam shells with their flippers and suck out the insides. Walruses can dive to 80m (300 ft), which is shallow for marine mammals, but they can stay down for as long as 30 minutes. While they are at the bottom they root around and drag their tusks through the silt and when feeding they 'rearrange' the sea floor, allowing the movement of many animals and the mixing of water. They have only two natural enemies, orcas and polar bears.
Records show the Vikings hunted walruses for their tusks and blubber as early as the 10th century. By the end of the 19th century, the walruses were hunted almost to extinction. They have since rebounded. The changes in global warming and reduction of the pack ice may cause problems for the female walruses and calves, as they give birth on the pack ice. They are not on the endangered species list, but are protected by the Marine Mammal Protection Act of 1972. Walruses are a very important link in the ecosystem of the Arctic.
The Arctic people of North America hunted them for food, bone tools, blubber, tusks and skin. Northern artists since prehistoric times have carved scenes on the walrus tusks and the white whalers also did carvings called scrimshaw. In Lewis Carroll's book, Through the Looking-Glass, he wrote a poem about a walrus called The Walrus and the Carpenter. I am the Walrus was a famous Beatles hit of 1967 written by John Lennon. This song was inspired by Lewis Carroll's poem.
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