Witnesses in Grand Teton and Yellowstone national parks have reported seeing bears or bear tracks, prompting park officials to warn visitors to be alert and begin carrying bear pepper spray in the backcountry.

Both parks are reporting at least one bear each, likely adult male grizzlies. The sightings came a little earlier than usual, most likely because of warm weather and scant snowfall so far this winter.

About 7:30 a.m. Feb. 1, a Grand Teton National Park employee riding a snowmobile on the Grassy Lake Road reported seeing a large grizzly near Polecat Creek.

“He was surprised to see a bear out,” said park spokeswoman Jackie Skaggs, who explained that bears who leave their dens early often rely on weakened ungulates or carcasses. “There are wintering elk and wintering bison in this Polecat Creek area.”

In Yellowstone National Park, wildlife officials confirmed bear tracks near Blacktail Deer Plateau — east of Mammoth — on Feb. 19. The Blacktail Deer Plateau is a bear management area that park officials usually close for several months a year to limit human-bear interactions, Yellowstone spokesman Al Nash said. Park biologists say the tracks might belong to two individual bears.

Finding bear tracks Feb. 19 is a little unusual for Yellowstone. In the last five years, the earliest bear sighting occurred Feb. 28, 2007, and the latest was March 8 or 9, 2008.

“It is a little early [to find bears out of their dens],” Nash said. “It’s not extraordinary, but it is early.

“We’ve had less snowfall this winter, at least so far,” he said. “This is kind of a rite of the season that says that spring is coming.” 

Kerry Gunther, bear management biologist for Yellowstone, said adult males typically come out first each year.

“We don’t know exact what causes them to come out,” he said. “It is typically timed when food is available for them. Snow melting into the den can sometimes get them up.”

Female bears with cubs of the year typically come out last, Gunther said.

“The cubs are still little,” he said. “They can’t really move about much. [Leaving the den later in the year] gives the cubs time to get a little bigger.”

Gunther said the mild winter probably has not resulted in a lot of winter-killed carcasses for bears to eat. However, the bears still could find food by claiming carcasses of ungulates killed by wolves.

Skaggs said backcountry winter travelers have been attacked by bears in the past. On March 7, 2001, a park employee named Jim Olson was skiing by head lamp into the Berry Creek backcountry cabin for a multi-day ski trip when a bear bit him in the back of the legs.

“I think [the bear] realized [Olson] wasn’t a food source,” Skaggs said, explaining that the bear was likely curious about Olson. “He skied on into the cabin, and he had some wounds that were pretty significant.”

Skaggs said Olson was airlifted out the following morning and has since recovered.