| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Order: | Carnivora |
| Family: | Odobenidae |
| Species: | O.rosmarus |
| Scientific Name: | Odobenus rosmarus |
The Walrus is a large marine mammal that is found inhabiting the freezing cold and
icy waters of the Arctic Circle.
The walrus is the only living species in the family Odobenidae and genus Odobenus.
This species is subdivided into three subspecies the Atlantic walrus which lives in
the Atlantic Ocean, the Pacific walrus which lives in the Pacific Ocean, and O. r.
laptevi, which lives in the Laptev Sea of the Arctic Ocean.
Walruses are incredibly sociable animals that live in large herds on the ice floes
that can contain up to thousands of individuals and consist mainly on females with
their young, along with a number of dominant males.
Walruses live mostly in shallow waters above the continental shelves, spending
significant amounts of their lives on the sea ice looking for benthic bivalve
mollusks to eat. Walruses are relatively long-lived, social animals.
Features
Tusks
The most prominent feature of the walrus is its long tusks. These are elongated
canines, which are present in both male and female walruses and can reach a
length of 1 m and weigh up to 5.4 kg.
Tusks are used to form and maintain holes in the ice and aid the walrus in
climbing out of water onto ice.
Tusks are slightly longer and thicker among males, which use them for fighting.
Vibrissae
Surrounding the tusks is a broad mat of stiff bristles, giving the walrus a characteristic whiskered appearance. There can be 400 to 700 vibrissae in 13 to 15 rows reaching 12inches in length, though in the wild they are often worn to much shorter lengths due to constant use in foraging. The vibrissae are attached to muscles and are supplied with blood and nerves, making them highly sensitive organs.
Skin
Walruses have large and elongated bodies that are wider at the head and neck and taper towards their tail which is embedded in a web of skin. Their tough and wrinkled skin is covered by a layer of sparse, coarse hairs and is generally grey or brown in colour. The walrus is sparsely covered with fur and appears bald.
Life
Walruses live to about 20–30 years old in the wild. Walruses most commonly breed in
the middle of winter between the months of January and March. The males reach sexual
maturity as early as seven years, but do not typically mate until fully developed at
around 15 years of age. The females begin ovulating as soon as four to six years
old. Breeding occurs from January to March.
The rest of the year, walruses tend to form massive aggregations of tens of
thousands of individuals on rocky beaches or outcrops.
Habitat
Walruses are found throughout the northern Atlantic and Pacific Oceans where they
inhabit ice floes and rocky coastlines, along with spending a great deal of time in
the freezing cold water. During the winter months when the ice is at it's thickest,
Walruses tend to prefer areas of thinner ice that they can easily break through to
the surface from the water underneath. In the warmer summer months when the ice
recedes, Walruses can be found more commonly on remote areas of rocky coastline.
The limited diving abilities of walruses brings them to depend on shallow waters and
the nearby ice floes for reaching their food supply.
Predation
Due to its great size and tusks, the walrus has only two natural predators: the
killer whale and the polar bear. Humans are the most common predators of the Walrus
as they are hunted for the meat, skin and oil.
The polar bear often hunts the walrus by rushing at beached aggregations and
consuming the individuals crushed or wounded in the sudden exodus, typically younger
animals.
Killer Whale regularly attack walrus, although walruses are believed to have
successfully defended themselves via counterattack.
Endangered Status
Near Threatened
Life Span
40 Years