Polar Bear
Ursus maritimus
Also known as Isbjørn, Nanuq
The Arctic's largest land predator — and, in practice, a marine one. Polar bears hunt seals from sea ice, which makes them closely linked to the extent of Arctic ice and one of the clearest examples of a species pressured directly by a warming climate.
As the Arctic’s apex predator, the polar bear tracks the health of the sea-ice system itself — an early signal of a warming climate.
How this species supports living systems
Functions → Services → RecipientsEach row is one complete path through the graph: the polar bear performs a function, which supports a service, which benefits a recipient. Functions and services are shared nodes — tap one to see every species and system connected to it.
What is weakened, layer by layer, if this is lost. Each step is a node in the graph — the effect propagates downstream toward human relevance.
Identity
A bear so dependent on the sea and sea ice that its scientific name means 'maritime bear'. It is classified as a marine mammal.
Conservation
Vulnerable means a high risk of endangerment in the wild. The central concern is not hunting but habitat: as Arctic sea ice shrinks, bears have less time and platform to catch the seals they depend on.
Distribution
Polar bears live right around the Arctic. Their range increasingly follows the seasonal sea ice they need to hunt.
Biology
- Largely solitary
- Roams long distances across sea ice
- Strong swimmer between ice floes
- Relies on sea ice to reach prey efficiently
Polar bears are built to hunt seals from the ice. Slow reproduction and long cub-rearing mean populations recover slowly from losses.
Ecological Intelligence
As the Arctic's apex predator, the polar bear's condition is widely treated as a signal of the health of the wider sea-ice ecosystem.
Threats & Solutions
Threat → Category → DriverLess and shorter-lasting sea ice is linked to less hunting time, longer fasting and poorer body condition.
Broader Arctic warming is associated with shifting prey and denning conditions beyond ice extent alone.
As an Arctic top predator, the polar bear accumulates persistent pollutants carried north and concentrated up the food chain.
As bears spend more time ashore, encounters with coastal communities are rising.
Cutting greenhouse-gas emissions — the only thing that addresses the root of sea-ice loss and climate pressures.
Cutting greenhouse-gas emissions is the only measure that addresses the root cause — sea-ice loss.
Tracking populations so gaps in data can be closed and trends caught early.
Tracking the 19 subpopulations is needed because trends vary widely between regions.
Helping farmers protect livestock so wildlife isn't killed in return.
Community deterrence and waste management reduce dangerous encounters as bears come ashore.
Phasing out and cleaning up harmful chemicals.
Reducing persistent pollutants lowers the toxic burden carried by Arctic predators.
Actively running parks and reserves so they work.
Protecting key denning and coastal areas supports resilience.
Importance Assessment
How much this species shapes its ecosystem.
How close the species is to disappearing.
Its significance to people and cultures.
How widely known the species is.
How much reliable data exists.
How relevant it is to 4PLANET missions.
Polar bear body condition and survival are linked to the extent and duration of Arctic sea ice.
Connections
First layer of the knowledge graphSources
Source keys reference the bodies this profile draws on. Full citations will connect to a dedicated source database in a later version. No citations are fabricated.
International Union for Conservation of Nature
Convention on International Trade in Endangered Species
U.S. National Oceanic and Atmospheric Administration
Smithsonian Institution