Polar bears are not classified as endangered, but they are considered vulnerable to extinction. The International Union for Conservation of Nature (IUCN) lists them as Vulnerable, meaning there is a significant probability their population will decline by more than 30% within three generations (roughly 45 years). In the United States, polar bears hold a slightly different label: threatened under the Endangered Species Act, a designation the U.S. Fish and Wildlife Service reaffirmed in September 2023.
What “Vulnerable” and “Threatened” Actually Mean
The distinction matters. “Endangered” means a species faces imminent risk of extinction. “Vulnerable,” one step below that on the IUCN scale, means extinction is a serious possibility if current trends continue. The IUCN concluded that polar bears warrant this classification because projected population declines cross the 30% threshold but likely fall short of 50%.
In the U.S., the Fish and Wildlife Service listed polar bears as threatened in 2008, specifically because of ongoing loss of sea ice habitat. A 2023 status review confirmed nothing has changed for the better. The agency’s Species Status Assessment found that polar bears still depend heavily on sea ice for hunting, traveling, and breeding, and that ice loss is accelerating in a warming Arctic.
Canada, home to roughly two-thirds of the world’s polar bears, classifies them as a species of “Special Concern” under its Species at Risk Act. That’s a notch below threatened, reflecting the fact that many Canadian subpopulations remain relatively stable for now.
How Individual Populations Are Doing
Scientists track 19 distinct polar bear subpopulations across the Arctic. Of those with enough data to assess, 3 are declining, 5 are stable, and 2 are actually increasing. The remaining populations lack sufficient data for a clear trend, which is itself a concern since some of the least-studied groups live in rapidly changing parts of the Arctic like East Greenland and the Laptev Sea.
Western Hudson Bay is the most closely watched declining population and serves as a bellwether for what sea ice loss does to bears over time. That group numbered roughly 1,185 in 1987. By 2011, it had fallen to 949. The most recent survey, in 2021, counted just 618 bears, a 27% drop in five years alone. The population is now about half the size it was in the 1980s. The decline is driven primarily by fewer adult females and cubs surviving. Pregnant bears simply run out of energy reserves before they can successfully give birth and raise young.
The two increasing populations, Kane Basin and M’Clintock Channel, were both heavily overhunted in the past. Their growth reflects reduced hunting pressure more than improving habitat conditions.
Why Sea Ice Loss Is the Central Threat
Polar bears hunt seals from platforms of sea ice. When ice breaks up earlier in spring and forms later in fall, bears are forced onto land where food is scarce. Research has identified fasting thresholds: cubs can survive roughly 117 days without food during ice-free periods, while adults can last somewhat longer. Once the ice-free season exceeds those limits, bears start dying.
The reproductive impact shows up before outright starvation. Female polar bears give birth to smaller litters when summer ice-free periods are longer. On average, only about 50% of polar bear cubs survive their first year. In regions experiencing the most severe ice loss, that number drops further. In Western Hudson Bay, the collapse in cub survival and adult female condition is what’s driving the population downward.
Projected Outlook
If current sea ice trends continue, an estimated two-thirds of the world’s polar bears could be lost by 2050. That projection comes from climate models linking Arctic warming to habitat availability. The timeline is not distant or abstract. Bears in southern populations like Western Hudson Bay and Southern Beaufort Sea are already experiencing the conditions that models predicted would cause declines, and those declines are happening on schedule.
Northern populations in the high Arctic still have more stable ice conditions, which is why some subpopulations remain steady or are even growing. But as warming progresses, those refuges shrink. The question is not whether northern bears will eventually face the same pressures, but when.
International Trade and Legal Protections
Polar bears are listed under Appendix II of CITES, the international treaty governing wildlife trade. This allows regulated commercial trade in polar bear parts (primarily hides and teeth from legal hunts) as long as exporting countries certify the trade is sustainable. Twice, in 2010 and 2013, proposals were made to move polar bears to Appendix I, which would have banned nearly all commercial trade. Both times, the majority of member nations voted the move was not yet warranted.
Hunting remains legal in Canada, Greenland, and parts of Alaska under quota systems managed by Indigenous communities. While overhunting was a serious threat decades ago, harvest levels today are generally set to remain sustainable. The far larger threat, and the one driving the species’ vulnerable status, is the continued loss of Arctic sea ice from climate change.