JACKSON - A grizzly bear mauled another Gillette hunter Sunday, this time disfiguring the man's face and sending him into surgery in Idaho Falls.

The hunter, whose name was not released, was about three miles south of Togwotee Pass near Dubois in Fremont County.

Sgt. Jerry Evagelatos with the Fremont County Sheriff's Office said the report indicated the hunter's "lower jaw is gone." The hunter also suffered a bite to his side. It was not the same bear that mauled a different Gillette man in September in Teton County.

The latest incident was reported to the sheriff's office at 11:01 a.m. Sunday. Evagelatos did not know who placed the call, but speculated it could have been one of the man's three hunting partners.

The report said the hunters were walking through timber trying to flush out an elk when they were attacked by a grizzly bear.

"All the injuries were to one person," Evagelatos said. "I don't know in what position he was in. About four shots were fired at the bear, as well as, they said, they emptied half a can of pepper spray, which apparently had no effect."

The group was finally able to chase off the bear. Evagelatos said he did not know the extent of the man's injuries.

The mauling is the second in less than two weeks in northwestern Wyoming. Wally Cash, another Gillette hunter, was mauled Sept. 21 near Moran while trying to flush an elk from timber.

Cash has a quarter-size steel plate above his ear where the grizzly took out part of his skull.

Sunday's mauling marks the fifth this year - more than three times the yearly average, according to Mark Bruscino, bear management specialist for the Wyoming Game and Fish Department.

"The last 10 years average 1.4 injuries per year," Bruscino said. Any sort of injury occurring after the bear makes contact with a person counts. A biker who had a confrontation with a grizzly bear near Togwotee Pass last month was not injured.

Two other injuries were to hunters, and a hiker at Brooks Lake was mauled.

Bruscino said because this year's whitebark pine crop is poor, bears are moving around more and looking for food.

"It increases the potential for people and bears to bump into each other," he said. "We see exactly this pattern … when foods fail."

When the crop is good, bears will stay at higher elevations and often not move around as much, he said.

Why the whitebark pine crop is poor this year is not known, Bruscino said.

"No one knows why there are these boom and bust years," he said. "It appears to follow no predictable pattern. It's not related to drought or moisture conditions."

Grizzly populations are increasing by about 3 percent or 4 percent every year, and have doubled in about 20 years, Bruscino said.

"Also more people every year are recreating in the outdoors," he said, which might explain the spike in maulings.

Still, bears don't perceive humans as a food source, Bruscino said. The last human killed by a grizzly was in 1986 when a camper in Pelican Valley in Yellowstone National Park was killed in her tent. Authorities don't know what prompted the killing.

"The reality is they view us just like another bear," Bruscino said. "If surprised, they usually run, but they may fight. Attacks follow that same pattern. Bears fight each other around the head and neck."

A few grizzlies are starting to den now, with peak den entrance during the first few weeks of November.

"Hopefully," Bruscino said, "it will start getting better."

Environmental reporter Whitney Royster can be reached at (307) 734-0260, or at royster@trib.com.