Wild polar bears live 15 to 18 years on average, and a few tagged bears have reached their early 30s, says Polar Bears International. Females usually outlive males: 20 to 25 years against 15 to 18, according to San Diego Zoo Wildlife Alliance. The oldest known polar bear, Debby, died in a Canadian zoo in 2008, aged 42.
| Group | Typical lifespan | Record or extreme | Source |
|---|---|---|---|
| Wild polar bears (all) | 15 to 18 years on average | A few tagged bears in their early 30s | Polar Bears International |
| Wild females | 20 to 25 years | No named record found | San Diego Zoo Wildlife Alliance |
| Wild males | 15 to 18 years | No named record found | San Diego Zoo Wildlife Alliance |
| Cubs | About half die in their first year | Survival is lower where sea ice is shrinking | Polar Bears International |
| Zoo polar bears | Often longer than wild bears | Debby: 42 years (died November 2008) | NBC News / Guinness |
| Grizzly bears, for comparison | About 25 years | Some over 35; an Alaskan brown bear reached 39 | USFWS; Alaska Dept. of Fish and Game |
How long do polar bears live in the wild?
The average wild polar bear lives 15 to 18 years (PBI). That average is dragged down by the many cubs that die young. A bear that survives its first few years has a much better chance of reaching its 20s.
Sex matters too. San Diego Zoo Wildlife Alliance gives wild females 20 to 25 years and males 15 to 18. Adult males fight each other for mates, and those fights can leave serious wounds, which may be one reason they die younger. Very few bears of either sex reach 30. Polar Bears International says biologists have tagged only “a few” bears in their early 30s.
Polar bears count as adults once they can breed. For females that is age 4 to 6, and for males 6 to 10 (PBI). A healthy female has cubs about every three years, so she may raise only a handful of litters in her whole life.
Why do so many polar bear cubs die young?
Only about 50% of cubs live past their first year, says Polar Bears International. Cubs weigh about 0.5 kg (1 lb) at birth and depend on their mother’s fat-rich milk. If she could not store enough fat before denning, she makes less milk and the cubs may starve.
Sea ice decides a lot of this. Where the ice melts early, mothers get less time to hunt seals, so cub survival drops (PBI). Cubs stay with their mother for about 2 to 3 years while they learn to hunt (PBI). Young bears that have just left her are clumsy hunters, so hunger is a big risk in their first years alone. Our polar bear life cycle page covers each stage.
How do scientists know how old a polar bear is?
They count rings in a tooth. Biologists pull a small premolar, a tooth between the canine and the molars, which the bear does not need. Each year a new layer of cementum grows around the root. Winter layers are dark and thin, and summer layers are light and thick, much like tree rings, explains the Alaska Department of Fish and Game.
In the lab, the tooth root is softened, cut into slices thinner than paper and stained purple. A trained reader then counts the rings under a microscope (ADF&G). That is how researchers know a wild bear really was in its early 30s. Tagging helps too: a bear first marked as a cub has a known birth year.
How long do polar bears live in zoos?
Zoo polar bears often live longer than wild ones. The record holder is Debby, a female at the Assiniboine Park Zoo in Winnipeg, Canada. She was found as an orphaned cub in the Russian Arctic in 1966 and lived at the zoo from 1967.
Guinness listed her as the world’s oldest polar bear when she turned 41. She died in November 2008, aged 42, after her organs began to fail, reports NBC News. She had six cubs.
You may see online that a zoo bear lived to 43 or 45. We found no reliable record of that, so treat those claims with care. Debby, at 42, is the documented record.
Why do polar bears live longer in captivity?
A zoo bear gets regular meals, a vet, and no rivals to fight. It never has to wait out a long ice-free summer with no seals to catch. Those are the main reasons zoo bears can outlive wild ones.
Zoos do not offer more space, though. Wild polar bears use a range of about 23 million km² (8.9 million sq mi) (Polar Bear Range States). Most keep to home ranges a few hundred kilometres across, and one tracked female walked nearly 4,800 km (3,000 mi) (PBI). No zoo can match that. See where polar bears live for the full range.
What kills adult polar bears?
- Hunger linked to sea ice loss. Bears need the ice to catch seals. The Government of Canada calls climate change the most important long-term threat to polar bears.
- Old age. Worn teeth and weaker bodies make hunting harder for older bears.
- Other polar bears. Males fight over mates, and adult males sometimes kill cubs.
- Conflict with people. Hungry bears near towns are sometimes shot to protect people.
- Legal hunting. Indigenous communities hunt polar bears under quotas. Canada says these are set on “principles of conservation and Aboriginal subsistence” and are “not market driven”. About 2% of Canada’s bears, around 300 a year, enter international trade (Government of Canada).
Adult polar bears have almost no natural predators. Our page on what eats polar bears explains the rare exceptions.
Are polar bear numbers going down?
It depends on where you look. The IUCN Polar Bear Specialist Group estimates about 26,000 polar bears worldwide, with a likely range of 22,000 to 31,000. Of the 20 subpopulations, 3 have likely or very likely decreased, 5 are likely stable, 2 have likely increased and 10 lack enough data to tell.
The clearest drop is in Western Hudson Bay, Canada, which fell to about 618 bears by 2021 (PBSG). So it is wrong to say every polar bear group is shrinking, but some clearly are. Polar bears are listed as Vulnerable by the IUCN. Read the full story in are polar bears endangered?
Do polar bears live longer than grizzly bears?
Not usually. Grizzly bears typically live about 25 years, and some pass 35, says the US Fish and Wildlife Service. The oldest brown bear documented in Alaska was a 39-year-old female (Alaska Department of Fish and Game). One likely reason is diet: grizzlies can switch between plants, fish and meat, while polar bears depend on seals. Compare the two bears in polar bear vs grizzly bear size.
Frequently asked questions
What is the oldest polar bear ever recorded?
Debby, a female at the Assiniboine Park Zoo in Winnipeg, Canada. She was found as an orphaned cub in the Russian Arctic in 1966 and died in November 2008, aged 42. Guinness listed her as the world's oldest polar bear. In the wild, a few tagged bears have reached their early 30s.
Do male or female polar bears live longer?
Females. San Diego Zoo Wildlife Alliance gives wild females a lifespan of 20 to 25 years and wild males 15 to 18 years. Males fight each other for mates, which may help explain the gap.
How long do polar bear cubs stay with their mother?
About 2 to 3 years. Polar Bears International gives 2.5 to 3 years on its life cycle page and 'just over two years' in its mom and cub facts. In that time the cubs learn to hunt seals, swim and survive the Arctic winter.
Can a polar bear live to 50?
There is no record of it. The oldest documented polar bear, Debby, died at 42 in a zoo with daily food and vet care. In the wild, the oldest tagged bears were in their early 30s, and most wild bears die before 20.
Sources
- Polar Bears International. Polar bear life span and life stages.
- San Diego Zoo Wildlife Alliance. Polar bear.
- NBC News (Associated Press) (2008). World's oldest polar bear dies at Canadian zoo.
- Polar Bears International. Top mom and cub facts.
- Alaska Department of Fish and Game. How old is my bear? Using a tooth to age animals.
- IUCN SSC Polar Bear Specialist Group (2024). Population status of the world's polar bear subpopulations.
- Government of Canada. Conservation of polar bears in Canada.
- Polar Bear Range States. Population, distribution and trends.
- Polar Bears International. Polar bear habitat.
- US Fish and Wildlife Service. Grizzly bear (Ursus arctos horribilis).
- Alaska Department of Fish and Game. Brown bear species profile.
Sources checked 15 September 2026.
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