It's called a "pizzly" or "grolar" bear, and is so rare only a handful of sightings have been confirmed in the wild -- and no one can say for sure how many even exist.
Until about 10 years ago, few believed this hybrid grizzly-polar bear even existed in the wild at all.
But earlier this month, one of these rare bears was shot and killed in Canada by 25-year-old hunter Didji Ishalook.
"It looks like a polar bear but it’s got brown paws and big claws like a grizzly," Ishalook told the Guardian. "And the shape of a grizzly head."
DNA samples from the bear have been sent out for testing, but experts think they already know what the results will say.
"I think it’s 99 per cent sure that it’s going to turn out to be a hybrid,” Ian Stirling, an emeritus research scientist with Environment Canada, told The Toronto Star.
The paper reports that the bear was legally killed as part of a program that allows Inuit to practice subsistence hunting.
Stirling explained that it can take several days to induce ovulation in a female bear.
"The fact that a grizzly and polar bear are mating tells you that they’re hanging out," he told the Star. "This isn’t just a casual one-night stand kind of thing."
The name of the hybrid bear depends on the father: If he's a grizzly, the baby is a grolar. If he's a polar bear, it's a pizzly, according to Nunatsiaq News.
As sightings become increasingly common, experts are debating the reasons for the seemingly growing number of hybrid bears.
"With climate change, grizzly bears are moving further north, so there is more overlap between grizzly bears and polar bears in terms of their range," bear expert Dave Garshelis of the Minnesota Department of Natural Resources told the CBC. "There are even American black bears that are moving further north. And a few black bears have been spotted outside of Arviat."
But not everyone is sold on that theory.
"We can’t say specifically, 'this is because of climate change,'" Nunavut carnivore biologist Malik Awan told Nunatsiaq News. "There’s many possible reasons. For example, there’s a lot going on in grizzly habitat in the South like habitat change, loss and fragmentation."
Whatever the reason, there seem to be more of them these days -- and that's bad news for the vulnerable polar bear: A 2010 report in Nature find that hybridization "can be the final straw in loss of species,” according to National Geographic.
"It is not a good thing for the future of polar bears that we see this hybridization occurring," bear expert Chris Servheen told Vice News. "And it's not going to result in some kind of new bear that is successfully living in the Arctic."