How Many Polar Bears Are Left?

The global polar bear population is thought to be between 22,000 and 31,000. These bears are divided into 19 subpopulations around the Arctic, with some containing fewer than 200 individuals and others consisting of more than 2,000.

Polar bears' rapidly dwindling populations serve as a symbol of the climate crisis globally, but are they technically endangered? Their conservation status may surprise you. Learn more about polar bear populations, the threats these animals face, and what we can do to save them from extinction.

Are Polar Bears Endangered?

Polar bears are listed as "vulnerable" on the IUCN Red List of Threatened Species, a designation they first received in 1982 and that was upheld by the latest assessment in 2015. They are protected by the Agreement on the Conservation of Polar Bears, a multilateral treaty signed in 1973 by the five polar bear nations: Canada, Denmark, Norway, Russia, and the U.S. This agreement prohibits unregulated hunting of polar bears, including the use of aircraft or large motorized vehicles to hunt them. It compels member states to take appropriate actions to preserve the ecosystems that sustain polar bears.

Although not technically endangered, the U.S. government has protected them under the Endangered Species Act since 2008, classifying them as threatened throughout their range. It's important to note that while these bears face potentially existential threats in some places, a few populations have rebounded in recent decades from overhunting in the last century, leading some people to argue polar bears are actually thriving.

The late U.S. Sen. Ted Stevens of Alaska was one of those people, saying in 2018 that "there are now three times as many polar bears in the Arctic than there were in the 1970s," a claim that has periodically resurfaced since. According to the IUCN, it's not clear which way polar bear populations are swinging on the whole. World Wildlife Fund data from 2019 shows that more subpopulations are declining than are increasing. The largest subpopulations look to be stable.

Limitations to the Data

Despite the encouraging rebound of some populations, there is little evidence to suggest polar bears are thriving overall. That's partly because there isn't enough long-term data on polar bears, especially for the northernmost regions.

Those who doubt their current plight have claimed that only 5,000 polar bears were left in the 1960s, but that claim is largely contested by conservation experts.

At least three polar bear populations are likely in decline, according to the IUCN Polar Bear Specialist Group (PBSG), but nine of the 19 subpopulations have insufficient data. There is too little data to even estimate population size for the three in decline.

While their specific status is more muddled than the overall outlook for climate change itself, there is significant evidence to suggest many polar bear populations are in peril.

How Is Climate Change Affecting Polar Bear Populations?

To understand why polar bears are threatened by climate change, you have to consider what polar bears eat and how they get their food. Polar bears are apex predators and a keystone species in their Arctic habitats, and their favorite food, by far, is seals. They specifically target ringed and bearded seals due to their high-fat content.

Polar bears spend about half their time hunting, typically by stalking seals from the sea ice and ambushing when they surface to breathe. They often travel long distances and wait hours or days for a single seal, and while only a fraction of their hunts succeed, it's generally worth the trouble for such a fatty meal.

Polar bears are considered marine mammals, but while they are excellent swimmers, they are no match for a seal in the water. Sea ice is therefore instrumental to their hunting strategy, and it's now declining due to rising Arctic temperatures, now warming at roughly twice the rate of the planet overall.

Arctic sea ice naturally waxes and wanes with the seasons, but its average late-summer minimum is now shrinking by 13% every decade, according to the NOAA. The oldest Arctic sea ice—frozen for at least four years, making it more resilient than younger, thinner ice—is now in steep decline. Whereas it comprised about 16% of the total ice pack in 1985, it now comprises less than 1%, representing a loss of 95% over just 33 years.

In 2020, Arctic sea ice reached its second-lowest extent since record-keeping began. This decline is alarming for several reasons: Arctic sea ice performs key services for the planet like reflecting solar heat and influencing ocean currents. It's even more directly important for polar bears, as less sea ice means fewer chances for them to catch seals.

The effects of climate change vary by location, and sea ice decline seems to be affecting some bears more than others. Western Hudson Bay had roughly 1,200 polar bears in the 1980s, for example, but that has since fallen to 842, and as Polar Bears International (PBI) notes, trends in their body condition, survival, and abundance have been linked to sea ice conditions. Bears in Southern Hudson Bay have also suffered a 17% decline since 2012, according to PBI, and their body conditions have similarly been linked to a longer ice-free period.

Most other subpopulations are either considered stable or lack sufficient data, but many will likely also face dire challenges from the loss of sea ice in their habitats. Some might be able to adapt, but their options likely will be limited. Even if they can exploit new food sources on land, they could face competition or conflict with established residents like brown bears and people.

Polar bears are slow to adapt due to their low reproductive rate and long time between generations. That doesn't bode well given the speed of modern climate change, already happening too quickly for many species to keep up.