Polar bears are listed as threatened under the US Endangered Species Act and as vulnerable by the International Union for the Conservation of Nature — a designation just short of endangered on both lists. Despite what you may have heard, the sea ice that makes up their hunting grounds has been diminishing by about 14 percent a decade, and the ice that does form freezes later and melts earlier.
Not only does shrinking sea ice make it harder for polar bears to hunt, but being ashore for longer periods means they’re at greater risk of being killed by humans. Meanwhile, as an apex predator, their bodies also build up high levels of toxic pollutants like mercury, pesticides, and chemicals used in flame retardants and non-stick coatings.
The Beaufort Sea population that Pagano studied has declined by about 40 percent since 2005. Previous studies found other animals are going without food longer than they did in the 1980s and 1990s, the study notes.
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Globally, the polar bear population is thought to be holding roughly steady at around 25,000-30,000, Andrew Derocher, who has studied the species Canada’s University of Alberta since the 1980s, told Seeker. But some populations have seen sharp declines, while other researchers have found bears in some communities are smaller and less heavy than they used to be, he said.
“The beauty of this study I think really comes from the fact that it’s an all-in-one,” Derocher said. “The researchers have done it all in one, in one place, in a set of animals. That’s never been done before like this.”
Derocher said since the study used a small sample size over a short period, follow-up research should follow more animals over a longer stretch. But he added, “I think it confirms all the reasons to be concerned about polar bears from a conservation perspective are intact.”
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