Marine mammals
Polar bear
Ursus maritimus
Revered and feared as Nanuq in Inuit mythology, where it is sometimes described as an almost-human spiritual ancestor for its intelligence, it is also classified as a marine mammal, given how much its life depends on sea ice and its swimming ability.

🗺️ Geographic range
The pack ice and coasts of the Arctic Ocean: Canada, Greenland, Svalbard, Siberia, Alaska.
📊 Population
Global population estimated by the IUCN at around 26,000 individuals, with a projected decline due to melting Arctic sea ice linked to climate change.
⚠️ Threats
Arctic sea ice melt
Climate change is reducing the sea ice it depends on to hunt seals, forcing it to fast for longer periods or travel greater distances.
Source: IUCN — Red List of Threatened Species
Habitat
- Arctic Ocean · Sea Ice · Epipelagic zone · Permanent
Behaviour
- Diet
- Seals, particularly ringed seals, stalked near breathing holes in the ice.
- Hunting
- Motionless for hours near a breathing hole, or stalks walruses and young narwhals isolated on the pack ice.
- Reproduction
- Delayed implantation; the female gives birth in a snow den, usually to two cubs.
Physiology
- Anatomy
- A thick layer of fat and a double-layered insulating coat, wide paws acting like snowshoes on the ice.
- Adaptations
- Can detect the scent of a seal through more than a metre of snow and ice, and swim continuously for over 100 km.
🔗 Web of marine life
⚡ Its extraordinary abilities
- Can smell a seal through more than a metre of compacted snow and ice
- Classified as a marine mammal: able to swim continuously for over 100 km in open sea
🏆 Records
The largest land carnivore still in existence
Males can exceed 700 kg.
Source: IUCN — Red List of Threatened Species
If you cross paths with this animal…
Risk: High: one of the few large land predators that actively regards humans as potential prey.
Behaviour: Opportunistic and determined, particularly as sea ice becomes scarcer.
Advice: Never approach, even from a distance: always travel with an armed guard in polar areas frequented by the species.
💡 Did you know?
- Called Nanuq in Inuit mythology, where it is sometimes seen as an almost-human spiritual ancestor.
- Its skin is actually black beneath a translucent coat that only looks white by reflecting light.