Walrus

The walrus is a large marine mammal characterized by its distinctive long tusks, whiskered snout, and thick blubber layer. It inhabits Arctic and sub-Arctic waters, relying on sea ice as a platform for resting, breeding, and accessing feeding grounds. Walruses are remarkable for their highly social behavior, forming large haul-out groups sometimes numbering in the thousands.

Arctic regions of Russia, Canada, Greenland, and the United States (Alaska)

Circumpolar distribution across the Arctic, including the Bering and Chukchi Seas (Alaska and Russia), Canadian Arctic Archipelago, Greenland, and the Barents and Laptev Seas of Russia.

Altitude and depth

Primarily forages at depths of 10-80 meters on the continental shelf, though dives up to 180 meters have been recorded.

Seasonal movements

Walruses undertake seasonal migrations tracking the advance and retreat of sea ice, moving to more southern haul-outs in summer when ice retreats and returning north as ice reforms in winter.

Shallow coastal Arctic waters, sea ice floes, and rocky or sandy haul-out beaches; walruses depend on continental shelf areas with abundant benthic invertebrates.

Adaptations to its environment

Thick blubber layer (up to 15 cm) provides insulation against frigid waters; specialized whiskers (vibrissae) detect prey in murky, dark seafloor sediments; tusks aid in hauling out onto ice and social displays.

Vulnerable (VU) according to IUCN, primarily due to observed and projected population declines linked to sea ice loss from climate change, which threatens critical resting and feeding habitat.

Estimated population

Approximately 225,000 individuals globally, with the Pacific population estimated at around 200,000 and Atlantic population much smaller; overall trend considered declining or uncertain.

Climate change and sea ice loss, increased human-Arctic industrial activity (shipping, oil and gas exploration), unsustainable hunting in some regions, and disturbance-related mass mortality events at crowded haul-outs.

Diseases and parasites

Walruses can be affected by parasitic worms, bacterial infections, and morbillivirus outbreaks; skin parasites and lungworms have also been documented in various populations.

Protected under the US Marine Mammal Protection Act, CITES Appendix III, and various national wildlife laws in Russia, Canada, and Greenland; co-management programs with Indigenous communities regulate subsistence harvest.

Recommended actions

Strengthen international climate policies to slow sea ice loss, regulate industrial activity in critical habitats, monitor haul-out disturbances, and expand community-based conservation and research programs.

Walruses have a rotund body covered in sparse, cinnamon-brown to pinkish-brown wrinkled skin, a broad muzzle with hundreds of thick whiskers, and prominent ivory tusks that grow throughout life.

Size

Males typically reach 2.7-3.6 meters in length; females are somewhat smaller at 2.2-3.1 meters.

Weight

Males weigh 800-1,700 kg; females weigh 400-1,250 kg, making males substantially larger.

Distinctive features

The most obvious distinguishing feature is the pair of elongated canine tusks present in both sexes, along with a uniquely bristly, mustache-like array of vibrissae used for foraging.

Differences between males and females

Males are notably larger and heavier than females, possess thicker skin on their necks and shoulders, and typically have longer, thicker tusks used in dominance displays.

Highly gregarious, walruses form large haul-out aggregations on ice or beaches, sometimes numbering in the thousands, with social hierarchies often established through tusk size and aggressive displays.

When it is active

Walruses are generally active both day and night, alternating between foraging bouts in water and extended periods of rest while hauled out on ice or land.

Diet

Primarily benthic invertebrate feeders, walruses consume large quantities of clams, mussels, and other mollusks, using suction to extract soft tissue from shells.

How it feeds and hunts

Walruses use their sensitive whiskers to locate prey buried in sea floor sediment, then create a suction seal with their mouth to extract soft-bodied invertebrates from shells, sometimes assisted by jets of water.

Communication

Walruses use an elaborate range of vocalizations including bell-like sounds, knocks, and whistles, especially during breeding displays, along with visual tusk displays and physical postures to communicate dominance.

Interactions with other species

Killer whales and polar bears are the primary natural predators of walruses, particularly targeting calves and weakened individuals; walruses may also compete with other pinnipeds for haul-out space.

Role in its ecosystem

As major benthic predators, walruses play a key role in structuring soft-sediment marine ecosystems by disturbing seafloor sediments while foraging, which influences invertebrate community composition.

Breeding occurs from January to March, with males competing vocally and physically for access to females; gestation lasts about 15-16 months due to delayed implantation, and typically a single calf is born.

Raising the young

Calves are cared for intensively by their mothers for up to two years, nursing extensively and often riding on their mother's back while swimming; social bonds between mother and calf remain strong throughout early life.

Maturity and lifespan

Females typically reach sexual maturity around 5-6 years, males around 7-10 years; walruses can live 20-30 years in the wild, sometimes longer in managed care.

Classification

Mammalia > Carnivora > Odobenidae > Odobenus > Odobenus rosmarus

Subspecies

Odobenus rosmarus rosmarus (Atlantic walrus, found in Canadian Arctic and Greenland), Odobenus rosmarus divergens (Pacific walrus, found in Bering and Chukchi Seas), and a debated Laptev walrus population sometimes classified as a third subspecies.

Scientific synonyms

Trichechus rosmarus (original Linnaean classification, 1758)

Recent studies

Recent tracking studies using satellite tags have documented walruses hauling out on land in unprecedented numbers as sea ice diminishes, highlighting behavioral shifts linked directly to climate change.

Genome and DNA

The walrus genome has been sequenced, revealing 2n=32 chromosomes; genetic studies have helped clarify subspecies divergence and historical population bottlenecks.

Compared with similar species

Unlike true seals (Phocidae) or sea lions (Otariidae), walruses represent a distinct pinniped family (Odobenidae) with unique tusks and specialized feeding adaptations, setting them apart from their closest pinniped relatives.

Walrus tusks can grow up to one meter long and are used for both social dominance displays and helping haul massive bodies onto ice; walruses can slow their heart rate to withstand frigid Arctic waters; some males can weigh as much as a small car.

Where and how to see it

Walruses are best observed at well-known haul-out sites such as Round Island in Alaska or Svalbard in Norway, typically during summer months when large aggregations gather on beaches.

Risks to humans

Walruses are generally not aggressive toward humans but can pose serious risks if threatened or approached too closely, given their massive size and sharp tusks; stampedes at haul-outs can also endanger nearby humans.

Human uses

Indigenous Arctic communities have historically hunted walruses sustainably for meat, blubber, and ivory tusks, which have traditionally been carved for tools and art; commercial exploitation historically drove population declines before regulations were established.

Myths and legends

Indigenous Arctic peoples, including the Inuit and Chukchi, have long revered the walrus in folklore and mythology, often depicting it as a powerful spirit animal linked to survival and the sea's abundance.