Walrus

The Walrus (Odobenus rosmarus) is a very large flippered marine mammal that is perhaps best known as a tough fighter who will battle with its large tusks if aggravated. It served ancient people as a symbol of power and it rightfully earned that position.

It looks very clumsy out of water, but when it is swimming it moves very fast and very strong. This large animal has one of the toughest migration patterns of any polar animal, and it is well adapted for just that. It has almost no natural predators, except for the killer whale, but even a killer whale can not take on a full grown walrus bull, it has to pick off the sick and old. These great animals live for over forty years grubbing on small creatures on the ocean floor diving up to three-hundred feet just to reach them.

Anatomy
The Walrus is a large, round creature covered in thick cinnamon-brown skin. It has four flippers used for mobility primarily in water. The flippers are hairless and very rough giving better traction when out of the water. The head of a Walrus is very small in proportion to the rest of the body. It has a large upper lip where thick quill-like whiskers grow. These whiskers are used in to greet other walruses and to search the muddy sea floor for shellfish. The whiskers are capable of picking up objects like fingers and can also be erected to show submission to a more dominant walrus (Knudtson, p15). The eyes of a walrus sit on either side of its head and are bulgy and bloodshot. It has two large nostrils on the center top of its snout that can close tight for swimming under water. Walruses have large chewing teeth that are not actually used for chewing. These teeth crack open different mollusks they find on the seafloor. For a long time many people thought that damage to their teeth was caused by clam shells, but this are most likely caused by pieces of sand and pebbles that are accidentally scooped into the mouth while eating. The most famous characteristic of the walrus is its large tusks. These tusks are actually the animal's canine teeth. The tusks grow between 80cm to 100cm. The tusks are used to determine social status and to battle for mates.

Reproduction
Mating occurs between the months of December and March. They males and the females meet up during migration to the south. The female walruses gather on the shore where they wait to be courted by the males. From there the males sit in the water and perform a mating ritual. The ritual is a song that consists of whistling noises, teeth clacking, and bell sounds. They do this on the surface of the water and under the water. The song is very extravagant lasting upwards of eight minutes each time the walrus dives to sing. Many people have related the singing to bells in the distance followed by a knocking noise (Knudtson, p61) If the males get to close to each other during this process they will fight with their tusks. When the female is impressed enough she leaves the ice pack to the water to mate. The average ratio of males walruses to female walruses is often somewhere between 1:5 and 1:15 so the males are required to mate with as many females as possible. The walrus is actually the least producing of the pinnipeds (fin-footed mammals). The females only have one calf every two to three years, and it takes around 10-15 years to reach sexual maturity. This is because of the very long forty year life span that walruses possess (Knudtson, pp 62-63).

Ecology
The Walruses habitat is in almost every part of the Arctic region. They travel in packs, nesting on ice packs and beaches. Walruses remain near the coast so that they have easy access to their food. They migrate every winter to warmer waters in the south but still very far north in the arctic circle. Walruses will be incredibly social with each other. They will often rest on the ice or land in large packs huddled all together even when there is plenty of room elsewhere and it is warm enough to survive without extra heat. It is essential for these creatures to stay in these large packs on the shore; this is where they nurse, have babies, and grow new hair. Walruses look strange moving on the land. They lumber around on their fins rather than scooting themselves along like a seal. However if you think walruses can walk you are quite wrong, walruses do not actually walk. Their flippers are to fragile to hold the enormous 2000lb. creature. Instead, they support most of their body weight on their belly. They step with their flippers and lurch along the ground or ice (Knudtson, p.37-38). Walruses are far more adapted for life in the sea rather than life on the land. As big as they are, once they get into the water they glide quickly and efficiently. While in the water there are actual air sacs in the walrus's neck that allow it to float, and even sleep in the water if needed. This floating also provides easy nursing for young walruses.

Walruses are predatory animals and very heavy eaters. Most adults will eat between 110 and 190 pounds marine invertebrates that live on the murky ocean floor. Most animals would feed on the large fish, but it seems that the walrus prefers to cruise the bottom sifting the mud with their thick whiskers and large tusks and eating the shellfish and other invertebrates they stumble upon. They prefer clams, whelks, and mussels to most food but have been known to eat jellyfish, marine worms, slow moving fish, and even unsuspecting birds floating on the surface (Knudtson, p69). By eating so many small creatures on the ocean floor the walrus cleans up the excess population on invertebrates. There are many fish that do this but they do not eat nearly as much food as a male walrus.

Tusks
Walruses are the only pinniped (fin-footed mammal) that has tusks, which are grotesque elongations of the upper canine teeth. It is their most important feature serving many purposes, and the key symbol of what a walrus looks like and it. A walruses tusk can show its age. The tusk follows a regular growing season and form rings like that of a tree, each ring indicates one year. Captive Walruses that have no tusks are not born that way, they have been de-tusked to prevent damage to their trainer, other walruses, and their environment.


 * The tusks are very vital weapons against enemies such as killer whales and seals.
 * The tusks are used in fights among fellow walruses and are often shown to look more threatening and warn other walruses that they are not to be messed with.
 * Tusks help a walrus move, a walrus will use its tusks to grab at the edge of the ice and pull itself up and out. It can also aid in moving around on the land and climbing on most anything.