At least three grizzly bears have been spotted in recent weeks in western Arctic communities, leading scientists and wildlife managers to wonder if warm weather is keeping the bears from hibernating.

One of those bears was shot dead last Wednesday near Inuvik, N.W.T., after it mauled three dogs belonging to resident Willie Simon. Two of the dogs were killed, while the third was seriously injured.

About 270 kilometres west, residents in Old Crow, Yukon, have reported seeing two grizzly bears near their community in the last few weeks.

Robert Bruce, who works with the Renewable Resources Council in Old Crow, told CBC News that the number of bear tracks he sees in the area suggests that more may be out there.

"It's just warm, really warm," Bruce said.

Catherine Lambert, a bear biologist with the Gwich'in Renewable Resources Board in Inuvik, said she is surprised the bear involved in Wednesday's attack was not already hibernating.

Lambert's studies have shown that the majority of bears in the region go into their dens mid- to late-October. Prior to this year, she said the latest she had ever seen a bear out was Nov. 5.

It is possible that some of the bears started hibernating, but then came out of their dens because of milder than usual weather, she said.

"So if there is a warm day, or if there's a lot of noise outside the den, it's not uncommon for the bear just to come and check it out, especially in early spring or late fall when it's not super-cold yet," Lambert said.

N.W.T. wildlife officers hope to release their findings sometime this week of an autopsy being conducted on the Inuvik bear.