Walrus
The walrus is an interesting mammal that is found in the Atlantic Ocean (Atlantic walrus) and the Pacific Ocean (Pacific walrus). It lives predominately in shallow water above the continental shelves and spends much of its time foraging on the sea bed for food. Its main threat comes from humans who have hunted it for its: ivory, meat, skin, oil, leather and bone – especially during the 19th and early 20th century, all around the Arctic region. This depleted the population of mainly the Atlantic walrus. Additionally, the walrus is sometimes preyed on by orcas and polar bears, usually the calves or injured ones.
Pacific walruses are 10-20 % heavier than the Atlantic walrus and can grow up to 13ft in length and can weigh up to 3,700 lbs. The hide of a walrus accounts for 20 % of its body weight, but the Atlantic walrus has shorter tusks and a flattened snout.
Copulation takes place in water and when a calve is born, it weighs up to 187 lb and is between 3 and 4 ft 7 inches in length. It lacks external ears and it swims like a seal. The gestation period lasts 15 to 16 months and calves are born during the spring migration. Walrus milk is high in protein and fat and the young can stay with their mother for up to 5 years. The male also helps with its development through doing things like helping it to learn to swim. A walrus can live between 20 and 30 years. Notably, all adults come together to protect the young.
The walrus has distinguishing tusks which can reach a length of 3 ft 3 inches and weigh up to 12 lb; they are longer and thicker in males who use them for fighting, display and dominance. Walruses also use their tusks to look after holes in the ice and to help them when they are climbing out of water onto the ice. The tusks, are in fact, elongated canines and are present in both sexes. In general, they have few teeth.
Another striking feature of the walrus, is its whiskers which can reach 12-inch in length, although foraging can reduce their size. They also possess thick skin (4-inch) which covers the thick blubber below. The males also have nodules called “bosses” around their neck and shoulders, and an air sac which enables them to sleep vertically in the water by bobbing up and down. Males have a penis bone (baculum) which is up to 25 inch in length!
When the walrus migrates, it usually congregates on rocky beaches or outcrops. The majority of Pacific walruses spend their summer north of the Bering Strait while the Atlantic walrus spends its time between the Canadian Arctic, across Greenland, Svalbard and the western part of Arctic Russia.
The diet of a walrus includes: molluscs, shrimps, crabs, tubeworms and small moving fish. It is able to suck meat out of organisms by using its mouth and tongue like a vacuum.
Walrus meat still forms an important part of some communities’ diet, who also use its tusk to create artwork. Some people also treat walrus tongue as a delicacy.
But happily, walrus hunts are now regulated in the US, Russia, Canada and Greenland. However, global climate change poses a threat to their existence through the reduction of the thickness of the ice on which they depend.
The walrus features in the religion and folklore of many Arctic people and it has even been mentioned in the work of the Beatles!
