Walrus

A massive Arctic marine mammal with iconic tusks — pinniped giant of the polar seas, weighing up to 2 tons, equipped with sensory whiskers that find clams in dark seabed mud.

Massive size

Walruses are among the largest pinnipeds (seals, sea lions, walruses), exceeded only by elephant seals:

Adult male Pacific walruses — up to 3.6 meters long and 2,000+ kg
Adult female Pacific walruses — typically 2.7-3 m and 800-1,200 kg
Atlantic walruses — slightly smaller than Pacific subspecies
Newborn calves — 60-90 cm and 50-75 kg (already substantial)

The size makes walruses near-immune to most predators as adults. Polar bears occasionally take young or weakened walruses, but adults are generally too large for any natural predator.

The famous tusks

Both male and female walruses have prominent tusks — actually elongated upper canine teeth that grow continuously throughout life:

Male tusks — up to 1 meter long and 5+ kg each
Female tusks — slightly smaller (60-80 cm)
Hollow at base, ivory-like material
Ages typically estimated by tusk wear and growth rings

The tusks serve multiple functions:

Combat — dominant males fight with tusks; serious injuries common
Climbing onto ice — using tusks to hook onto ice edges
Status display — long tusks indicate dominant individuals
Defense — against polar bears and other threats

Whisker sensitivity

Walruses have about 450 vibrissae (whiskers) on their muzzle — among the most sensitive sensory hairs of any mammal. The whiskers:

Detect tiny vibrations of buried clams
Distinguish prey species in seabed mud
Function in low-light Arctic waters where vision is limited
Each connect to dedicated sensory neurons

Walruses essentially “see” the seabed through their whiskers — feeling for clams, mussels, and other shellfish in dark muddy water. They can identify suitable prey at remarkable distances using whisker information alone.

Clam vacuums

Walruses’ primary food is clams and other bivalves — and their feeding method is unique:

Diving to seabed — typically 50-100 meters
Locating clams via whiskers
Creating water suction with cheeks and tongue
Vacuuming clam meat from shells (often without breaking shells)
Spitting empty shells back to seabed

A single adult walrus can consume 3,000-6,000 clams per day — an enormous food intake reflecting their massive size. The feeding causes significant bioturbation of seabed mud, mixing nutrients up from deep sediment.

Massive haul-outs

Walruses gather in enormous social groups when resting on land or ice — called “haul-outs”:

Typically dozens to hundreds of animals
Sometimes thousands at major haul-out sites
Animals pile on each other for warmth
Vocalizations create chorus of grunts, bellows, knocks
Mothers and calves stay together within larger groups

The haul-outs are essential resting periods between feeding bouts. Walruses can’t sustain continuous swimming — they must rest on solid surfaces (ice or land) regularly.

Climate change crisis

Sea ice loss is severely affecting Pacific walruses:

Traditional ice-floe haul-outs disappearing
Walruses forced onto crowded land beaches
Mass mortality events — stampedes when groups are disturbed
Females and calves separated from preferred feeding areas
Calf mortality elevated due to crowded conditions

Several major haul-out events have featured 30,000-100,000 walruses crowded onto small Alaskan and Russian beaches, with significant mortality from stampedes. The changes are well-documented and concerning, though not yet population-threatening.

Ivory trade history

Walrus tusks were a major commercial product for centuries:

Inuit and indigenous Arctic peoples — traditional use for tools, art, and trade
Vikings — major source of luxury ivory; replaced by African elephant ivory
19th-20th century commercial harvest — significantly depleted populations
Modern regulations — strict limits on harvest, with subsistence rights for indigenous peoples

The 1972 US Marine Mammal Protection Act and subsequent international agreements significantly reduced commercial walrus killing. Modern populations are recovering, though climate change is the new dominant threat.

Walrus social bonds are notably strong:

Mother-calf bonds persist for 2-3 years (long for marine mammals)
Females form lasting same-sex friendships
Adult males form bachelor groups during non-breeding season
Distinctive individual recognition via vocalizations and visual cues
Cooperative defense of calves and weaker individuals

The social complexity has made walruses subjects of significant behavioral research, particularly in Russia and Alaska.