Odobenidae
Odobenidae is a family of marine mammals that includes only one extant species, the walrus (Odobenus rosmarus). The family is characterized by its large size, tusks, and thick blubber layer. Odobenidae is closely related to seals and sea lions, and they are all grouped within the suborder Pinnipedia. This family is believed to have evolved around 20 million years ago and originated in the North Pacific Ocean.
Common Names
The family Odobenidae is commonly known as "walruses." There are two distinct species: the Atlantic walrus (Odobenus rosmarus rosmarus) and the Pacific walrus (Odobenus rosmarus divergens).
Characteristics
Walruses are distinguished by several key features:
- Large size: Walruses are the largest pinnipeds, with males typically reaching lengths of 2.7 to 3.6 meters (8.9 to 11.8 feet) and weights of 1,000 to 1,500 kilograms (2,200 to 3,300 pounds). Females are smaller, averaging about 2.4 to 2.7 meters (7.9 to 8.9 feet) long and weighing 600 to 800 kilograms (1,300 to 1,800 pounds).
- Tusks: Both males and females have prominent tusks, which are actually elongated upper canine teeth. These tusks can be up to 1 meter (3.3 feet) long and are used for digging for clams and other food, fighting, and hauling themselves onto ice floes.
- Thick blubber layer: Walruses have a thick layer of blubber, which helps insulate them in cold water and provides energy reserves during periods of food scarcity.
- Pectoral flippers: Walruses have powerful pectoral flippers that are used for swimming and hauling themselves onto land.
- Short, thick fur: Walruses have short, thick fur that provides some insulation in cold water.
Environment
Walruses are found in the Arctic and subarctic regions of the Northern Hemisphere. They inhabit coastal waters, ice floes, and beaches. They are particularly common in the Bering Sea, Chukchi Sea, and the waters around Greenland and Svalbard.