The walrus (Odobenus rosmarus) is a large flippered marine mammal with a discontinuous distribution about the North Pole in the Arctic Ocean and subarctic seas of the Northern Hemisphere. The walrus is the only living species in the family Odobenidae and genus Odobenus. This species is subdivided into two subspecies: the Atlantic walrus (O. r. rosmarus ), which lives in the Atlantic Ocean, and the Pacific walrus (O. r. divergens ), which lives in the Pacific Ocean. Walruses are relatively long-lived, social animals, and they are considered to be a "keystone species" in the Arctic marine regions. They have also played a prominent role in the cultures of many indigenous Arctic peoples, who have hunted walruses for their meat, fat, skin, tusks, and bone.
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DiurnalDiurnal animals are active during the daytime, with a period of sleeping or other inactivity at night. The timing of activity by an animal depends ...
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CarnivoreA carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of a...
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MolluscivoreA molluscivore is a carnivorous animal that specializes in feeding on molluscs such as gastropods, bivalves, brachiopods, and cephalopods. Known mo...
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ScavengerScavengers are animals that consume dead organisms that have died from causes other than predation or have been killed by other predators. While sc...
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SemiaquaticSemiaquatic animals are those that are primarily or partly terrestrial but that spend a large amount of time swimming or otherwise occupied in wate...
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PrecocialPrecocial species are those in which the young are relatively mature and mobile from the moment of birth or hatching. Precocial species are normall...
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NatatorialNatatorial animals are those adapted for swimming. Some fish use their pectoral fins as the primary means of locomotion, sometimes termed labriform...
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TerrestrialTerrestrial animals are animals that live predominantly or entirely on land (e.g., cats, ants, snails), as compared with aquatic animals, which liv...
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CongregatoryCongregatory animals tend to gather in large numbers in specific areas as breeding colonies, for feeding, or for resting.
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ViviparousAmong animals, viviparity is the development of the embryo inside the body of the parent. The term 'viviparity' and its adjective form 'viviparous'...
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PredatorPredators are animals that kill and eat other organisms, their prey. Predators may actively search for or pursue prey or wait for it, often conceal...
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PolygynyPolygyny is a mating system in which one male lives and mates with multiple females but each female only mates with a single male.
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ColonialColonial animals live in large aggregations composed of two or more conspecific individuals in close association with or connected to, one another....
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Dominance hierarchyA dominance hierarchy (formerly and colloquially called a pecking order) is a type of social hierarchy that arises when members of animal social gr...
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Highly socialHighly social animals are those which are highly interactive with other members of their species. They live in large groups, nest in colonies, and ...
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Not a migrantAnimals that do not make seasonal movements and stay in their native home ranges all year round are called not migrants or residents.
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Canada Province AnimalsThe walrus has a short muzzle, a broad head, small eyes, whiskers, tusks, and flippers. Their large front flippers each have five digits. Males and females both have large tusks used for defense, getting out of the water, and cutting through ice. These are elongated canines, which are present in both male and female walruses and can reach a length of 1 m (3 ft 3 in) and weigh up to 5.4 kg (12 lb). Young walruses are deep brown and grow paler and more cinnamon-colored as they age. Old males, in particular, become nearly pink. Because skin blood vessels constrict in cold water, the walrus can appear almost white when swimming. Males also acquire significant nodules, called "bosses", particularly around the neck and shoulders. Walruses have an air sac under their throats which acts like a flotation bubble and allows them to bob vertically in the water and sleep.
Walruses live throughout the Pacific and northern Atlantic Oceans on rocky coastlines and ice floes. They spend most of their time in shallow waters (and the nearby ice floes) hunting for food. Despite suiting freezing northern conditions, walruses have ventured further south to Central Canada and the United Kingdom, even near the Spanish coast.
Walruses are extremely sociable animals, living in large herds of up to thousands in number, mainly females with their young, and some dominant males. Male walruses fight with their tusks to compete for females and establish dominance. They make a variety of sounds including loud bellows produced via two pouches of air that are in their necks. These animals are diurnal. When not in the water, they feed and rest on sea ice. Walruses prefer shallow shelf regions and forage primarily on the seafloor, often from sea ice platforms. They are not particularly deep divers compared to other pinnipeds but can dive to depths beyond 500 meters. When feeding on their favorite mollusks, walruses find them by grazing along the sea bottom, searching and identifying prey with their sensitive vibrissae, and clearing the murky bottoms with jets of water and active flipper movements.
Walruses are carnivores (molluscivores) and hunt other animals to survive. They eat clams, snails, worms, octopuses, squid, and some types of slow-moving fish. They will eat young seal carcasses when food is scarce.
Walruses are polygamous meaning that males mate with more than one female. Breeding occurs between January and March. After the gestation period of about 15 months, females give birth to a single pup is produced. Calves weigh 45 to 75 kg (99 to 165 lb) at birth and are able to swim. The females nurse their young for over a year before weaning, but calves can spend up to 5 years with their mothers. They drink only their mother's milk for 6 months and then start to eat solid foods. Young females can reproduce at about 6 or 7 years but males not until they are 10, though 5 years later when they have proved their dominance might be more successful.
Humans are a threat, hunting them for their hides, bones, tusks, and oil. Water pollution is also a threat in certain areas. Potential threats are climate change and global warming causing changes and loss of suitable habitats and an increase in shipping and development of oil and gas fields.
According to IUCN, the overall population of the walrus is likely greater than 225,000 individuals, comprising about 25,000 Atlantic walruses and 200,000 Pacific walruses. Currently, this species is classified as Vulnerable (VU) on the IUCN Red List.
Walruses are considered to be a "keystone species" in the Arctic marine regions. They feed on large numbers of organisms and their foraging has a large peripheral impact on benthic communities. When foraging walruses disturb the seafloor, releasing nutrients into the water column; this way they encourage the mixing and movement of many organisms and increase the patchiness of the benthos.
