Ottawa - Tests confirmed that a bear killed by a US hunter in Canada's far north last month is the first Grizzly-Polar bear cross ever discovered in the wild, officials said on Wednesday.

"It actually is a hybrid," said Judy McLinton, a spokeswoman for the Northwest Territories' environment and natural resources department in Yellowknife.

Jim Martell, 65, who paid C$50 000 (about R271 350) to hunt Polar bears, shot the animal, described by local media as a "pizzly", a "grolar bear", or Martell's favourite, a "polargrizz" on April 16.

The Idaho native told The National Post: "Everybody thought it was a Polar bear, and then they started looking more and more and they seen other features that resembled some of a Grizzly as well."

The bear had thick, creamy white fur, typical of Polar bears, but its long claws, humped back and shallow face, as well as brown patches around its eyes, nose, back and on one foot are Grizzly traits.

Geneticists have linked the two species. They believe Grizzly bears ventured north about 250 000 years ago to hunt seals and that their fur turned white over time. Thus, the Polar bear was born.

Odd couples have produced mixed offspring in captivity.

But this is the first discovery of this mixed breed in the wild, officials said.

The two species mate at different times of the year and inhabit vastly different regions - one lives on Arctic ice floes, the other in forests.

But hunters have reported seeing Grizzlies further north in recent years as the Arctic warms, said Andy Carpenter, mayor of Sachs Harbour, a tiny hamlet on Banks Island where the bear was shot.

"The only way they could get here is by walking across the ice," he said.

A laboratory in western Canada examined the bear's DNA to make the determination.