Polar Bear

The polar bear is the largest land carnivore and is uniquely adapted to life on Arctic sea ice, where it primarily hunts seals. Found across the circumpolar Arctic, it is a marine mammal in behavior despite being classified as a terrestrial carnivore. It is an iconic symbol of climate change due to its heavy dependence on shrinking sea ice habitat.

Arctic regions including Canada, Greenland, Norway (Svalbard), Russia, and the United States (Alaska)

Circumpolar distribution across the Arctic, including northern Canada, Greenland, Svalbard (Norway), the Russian Arctic coast, and Alaska (USA); found from roughly 66°N to the North Pole.

Altitude and depth

Sea level habitat; dives typically shallow (a few meters) but can swim long distances in open water.

Seasonal movements

Pregnant females enter maternal dens in autumn and give birth in winter, emerging in spring; sea ice extent drives seasonal movement patterns, with bears following ice edges as they expand and retreat.

Sea ice, coastal areas, and open Arctic Ocean waters; also uses tundra habitats during ice-free periods, especially pregnant females who den on land or stable ice.

Adaptations to its environment

Thick layer of blubber and dense fur provide insulation against extreme cold; large paws act as paddles for swimming and snowshoes for walking on ice; black skin under white fur absorbs heat, and a keen sense of smell helps locate seals under snow and ice.

Vulnerable (VU) according to IUCN, primarily due to observed and projected declines from sea ice loss driven by climate change, with some subpopulations experiencing significant declines while others remain stable or data-deficient.

Estimated population

Approximately 22,000-31,000 individuals globally, with an overall declining trend though some subpopulations are stable and others are declining or increasing depending on regional ice conditions.

Climate change causing sea ice loss and habitat fragmentation, pollution (including persistent organic pollutants), oil and gas development, and increasing human-bear conflict as bears spend more time on land.

Diseases and parasites

Susceptible to parasites such as Trichinella (from seal meat), and studies have documented exposure to various pathogens including morbillivirus and toxoplasma in some populations.

Protected under the 1973 International Agreement on the Conservation of Polar Bears, national laws in all range states, CITES Appendix II listing, and monitoring by the IUCN Polar Bear Specialist Group; some countries regulate subsistence hunting quotas.

Recommended actions

Global reduction of greenhouse gas emissions to slow sea ice loss, continued international cooperation on hunting quotas, reduction of Arctic industrial pollution, and expanded habitat monitoring and conflict mitigation programs.

Thick white to yellowish fur covers the body, with black skin visible on the nose and paw pads; the body is stocky with a long neck and narrow skull compared to other bear species.

Size

Body length typically 1.8-2.5 meters (males larger), with shoulder height around 1.2-1.6 meters when on all fours.

Weight

Males typically weigh 350-700 kg (occasionally up to 800 kg), while females are smaller, usually weighing 150-300 kg.

Distinctive features

Distinguished from other bears by its white coat, elongated neck, smaller ears, and specialized adaptations for aquatic life such as partially webbed paws and a streamlined body shape.

Differences between males and females

Males are significantly larger and heavier than females, often nearly twice the body mass, with broader heads and thicker necks.

Largely solitary except for mothers with cubs or temporary gatherings at abundant food sources like whale carcasses; adult males may compete aggressively during mating season.

When it is active

Primarily active during daylight hours but can be active at any time, especially during continuous summer daylight or winter darkness in polar regions.

Diet

Primarily carnivorous, feeding mainly on ringed and bearded seals; will also scavenge whale carcasses, walruses, seabirds, eggs, and occasionally vegetation when prey is scarce.

How it feeds and hunts

Uses 'still-hunting,' waiting motionless at seal breathing holes in the ice, and stalking seals resting on ice, sometimes breaking through ice to reach dens.

Communication

Communicates through body language, vocalizations such as huffs, growls, and roars, and scent marking via paw glands and urine to signal territory or reproductive status.

Interactions with other species

Apex predator with no natural predators as adults, though cubs may be vulnerable to adult male bears; competes with Arctic foxes for scavenged food and occasionally interacts with orcas in open water.

Role in its ecosystem

Serves as an apex predator regulating seal populations and is a key indicator species for Arctic ecosystem health, with its presence reflecting the state of sea ice habitats.

Mating occurs in spring (March-May); implantation is delayed until autumn, with births occurring in winter dens, typically producing 1-3 cubs after a gestation period of about 195-265 days including delayed implantation.

Raising the young

Females raise cubs alone, nursing and protecting them in a den through the first months of life, and cubs typically stay with their mother for about 2.5 years learning hunting skills.

Maturity and lifespan

Sexual maturity typically reached at 4-6 years for females and 6-8 years for males; average lifespan in the wild is 15-18 years, with some individuals reaching 25-30 years, and longer in captivity.

Classification

Mammalia > Carnivora > Ursidae > Ursus > Ursus maritimus

Subspecies

No universally recognized subspecies; polar bears are typically divided into 19 subpopulations across the Arctic based on geography rather than formal subspecies designation.

Scientific synonyms

Thalarctos maritimus (older classification), Ursus marinus

Recent studies

Recent studies using satellite tracking and genomic analysis have revealed declining body condition linked to reduced sea ice, as well as documented hybridization with grizzly bears in areas of range overlap due to shifting habitats.

Genome and DNA

Polar bears have 2n=74 chromosomes; genomic studies have shown close genetic relation to brown bears with evidence of interbreeding and hybridization events in evolutionary history.

Compared with similar species

Closely related to the brown bear (Ursus arctos), with polar bears being more specialized for aquatic and cold environments, having smaller ears, a longer neck, and completely different fur coloration and diet specialization.

Polar bears can swim continuously for over 100 km without resting; their fur is not actually white but translucent, appearing white due to light scattering; and their skin underneath is black to help absorb heat.

Where and how to see it

Best observed in areas like Churchill, Manitoba (Canada) during autumn migration, or Svalbard, Norway during summer boat expeditions, with responsible guided tours recommended for safety and minimal disturbance.

Risks to humans

Can be dangerous to humans, particularly in areas of increased human-bear encounters due to habitat loss; attacks are rare but potentially fatal, especially when bears are food-stressed.

Human uses

Historically hunted for fur, meat, and cultural/subsistence purposes by Indigenous Arctic communities; today, legal subsistence hunting continues under regulated quotas, and ecotourism has become a significant economic use.

Myths and legends

Polar bears hold deep cultural and spiritual significance for Arctic Indigenous peoples such as the Inuit, who view them as powerful spiritual beings and sometimes as ancestral or shamanic symbols.