An American sport hunter might end up in court after killing an odd-looking bear north of Sachs Harbour in the Northwest Territories.

Jim Martell was out hunting polar bear on the tundra near Sachs, 1,150 kilometres north of Yellowknife, when his local guide spotted the animal.

"Well, the guide, he said 'shoot', and he's a longtime guide there in Sachs Harbour and he knows what a polar bear is," said Martell, who had a permit for the hunt.

"I'd seen other polar bears while I was hunting and he looked just like [one] to me. So I wouldn't have hesitated and I don't think any other hunter would have."

But now the outfitter says the animal might be a cross between a polar bear and a grizzly. The fur isn't bright white like that of a polar bear, or brown like a grizzly's. It's more a dirty blonde.

Hide confiscated for DNA testing

A wildlife officer confiscated the hide from Martell on Tuesday and the Department of Environment is taking a DNA sample. If it's a grizzly, Martell could be charged with illegal possession of wildlife because he didn't have a permit to hunt that type of bear.

Now facing a fine of $1,000 or a year in jail, Martell's not impressed.

"Y'know, I've spent $50,000 here. And ... to come back with nothing, I don't think that's fair," he said.

"But I have recourses I think, maybe. I'm not going to let it go."

Cross-species love?

Although grizzly bears have been known to travel to the Arctic islands, they generally stay on the mainland.

Ian Sterling, a research scientist who has been studying polar bears in the Beaufort Sea region for more than 30 years, says if the reports are true, the bear is unlike anything he's ever seen.

He said it's hard to say if the animal is the product of cross-species love.

"The probability of a grizzly and a polar bear actually mating is actually pretty low," he said. "Partly because polar bears mate on the sea ice and grizzly bears mate on the land."

The Department of Environment says it will keep the mysterious bear hide until the investigation is over.