1911 Encyclopædia Britannica/Walrus

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WALRUS, or Morse (Odobenus rosmarus), a large marine mammal allied to the seals, representing a family by itself. The former word is a modification of the Scandinavian vallross or hvalros ("whale-horse"), the latter an adaptation of the Russian name for the animal. A full-grown male walrus measures from 10 to 11 ft from the nose to the end of the short tail, and is a heavy, bulky animal, especially thick about the shoulders. The head is rounded, the eyes are rather small, and there are no external ears. The muzzle is short and broad, with, on each side, a group of stiff, bristly whiskers, which become stouter and shorter in old animals. The tail scarcely projects beyond the skin. The fore-limbs are free only from the elbow, the fore flipper is broad, flat and webbed, the five digits being of nearly equal length, but the first slightly the longest. Each digit has a small flattened nail, situated on the inner surface at a considerable distance from the end. The hind-limbs are enclosed in the skin of the body, almost to the heel. The free portion when expanded is fan-shaped, the two outer toes (first and fifth) being the longest, especially the latter. Flaps of skin project considerably beyond the bones of the toes. The nails of the first and fifth toes are minute and flattened; those of the second, third and fourth elongated, sub-compressed and pointed. The soles of both fore and hind feet are bare, rough and warty. The surface of the skin generally is covered with short, adpressed hair of a light yellowish-brown colour, which, on the under parts of the body and base of the flippers, passes into dark reddish-brown or chestnut. In old animals the hair becomes more scanty, sometimes almost disappearing, and the skin shows evidence of the rough life and pugnacious habits of the animal in the scars with which it is usually covered. It is everywhere more or less wrinkled, especially over the shoulders, where it is thrown into deep and heavy folds.

One of the most striking characteristics of the walrus is the pair of tusks which descend almost directly downwards from the upper jaw, sometimes attaining a length of 20 in. or more. In the female they are as long or sometimes longer than in the male, but less massive. In the young of the first year they are not visible. These tusks correspond to the canine teeth of other mammals. All the other teeth, including the lower canines, are much alike—small, simple and one-rooted, and with crowns, rounded at first, but wearing to a flat or concave surface. Many of the teeth are lost early, or remain through life in a rudimentary state concealed beneath the gum. The tusks are formidable weapons of defence, but their principal use seems to be scraping and digging among sand and shingle for the molluscs and crustaceans on which the walrus feeds. They are said also to aid in climbing up the slippery rocks and ledges of ice on which so much of the animal's life is passed. Walruses are more or less gregarious in their habits, being met with generally in companies or herds of various sizes. They are only found near the coast or on large masses of floating ice, and rarely far out in the open sea, and, though often moving from one part of their feeding-ground to another, have no regular migrations. Their young are born between April and June,

The Atlantic Walrus (Odobenus rosmarus)

usually but one at a time, never more than two. Their strong affection for their young, and their sympathy for each other in danger, have been noticed by all who have had the opportunity of observing them in their haunts. When one is wounded the whole herd usually join in defence. Although harmless and inoffensive when not molested, they exhibit considerable fierceness when attacked, using their tusks with tremendous effect either on human enemies who come into too close quarters or on polar bears, the only other adversary they can meet with in their own natural territory. The voice, a loud roaring, which can be heard at a great distance, is described by Dr Kane as "something between the mooing of a cow and the deepest baying of a mastiff, very round and full, with its bark or detached notes repeated rather quickly seven or nine times in succession."

The principal food of the walrus consists of bivalve molluscs, especially Mya truncata and Saxicava rugosa, two species very abundant in the Arctic regions, which it digs up from the mud and sand in which they lie buried at the bottom of the sea by means of its tusks. It crushes and removes the shells by the aid of its grinding teeth and tongue, and swallows only the soft parts of the animal. It also feeds on other molluscs, sand-worms, starfishes and shrimps. Portions of various kinds of seaweed have been found in its stomach, but whether swallowed intentionally or not is doubtful.

The commercial products of the walrus are its oil, hide (used to manufacture harness and sole-leather and twisted into tiller ropes) and tusks. The ivory of the latter is, however, inferior in quality to that of the elephant. Its flesh forms an important article of food to the Eskimo and Chukchi. Of the coast tribes of the last-named people the walrus formed the chief means of support.

Walruses are confined to the northern circumpolar regions, extending apparently as far north as explorers have penetrated. On the Atlantic coast of America the Atlantic species was met with in the 16th century as low as the southern coast of Nova Scotia, and in the last century was common in the Gulf of St Lawrence and on the shores of Labrador. It still inhabits the coast round Hudson's Bay, Davis Strait and Greenland, where, however, its numbers are decreasing. It is not found on the Arctic coast of America between the 97th and 158th meridians. In Europe, occasional stragglers have reached the British Isles; and it was formerly abundant on the coasts of Finmark. It is rare in Iceland, but Spitzbergen, Novaia Zemblia and the western part of the north coast of Siberia are constant places of resort. The North Pacific, including both sides of Bering Strait, northern Kamchatka, Alaska and the Pribyloff Islands are also the haunts of numerous walruses, which are isolated from those of the North Atlantic by long stretches of coast in Siberia and North America where they do not occur. The Pacific walrus appears to be as large as, if not larger than, that of the Atlantic; its tusks are longer and more slender, and curved inwards; and the whiskers are smaller, and the muzzle relatively deeper and broader. These and certain other differences have led to its being considered specifically distinct, under the name of Odobenus obesus. Its habits appear to be similar to those of the Atlantic form. Though formerly found in immense herds, it is becoming scarce, as the methods of destruction used by American whalers are more certain than those of the Chukchi, to whom the walrus long afforded the principal means of subsistence.

Fossil remains of walruses and closely allied animals have been found in the United States, and in England, Belgium and France, in deposits of late Tertiary age.  (W. H. F.; R. L.*)