An aerosol spray may be the best protection that hikers, fishers and hunters can carry in bear country, according to a wildlife expert at Brigham Young University.

Tom S. Smith, associate professor in the plant and wildlife sciences department at the Provo school, is a co-author of a report in the Journal of Wildlife Management, summarizing records of human-bear confrontations in Alaska going back 20 years. Their finding: Bear spray, a potent combination of chemicals shot from an eight-ounce can, stops a charging grizzly bear in its long-clawed tracks. Same for black and polar bears.

Though the spray can temporarily incapacitate a bruin, it's not deadly, as noted by one manufacturer's Web site: "Animals and people temporarily experience intense burning sensations, which wear off in 30 to 45 minutes. Counter Assault is nonlethal, has no ozone-depleting chemicals, and causes no permanent damage to the animal or person sprayed."

"I've worked in Alaska on bears and bear safety issues and bear-human conflict for 16, 17 years," Smith said during a telephone interview. He and his colleagues just want to give the best information they can, he said. The colleagues, according to BYU, are Stephen Herrero, professor emeritus at the University of Calgary; Terry D. Debruyn of the National Park Service; and James M. Wilder of the U.S. Minerals Management Service. The report also relied on an earlier study of a decade's worth of data.

The findings are controversial as some people and agencies were unwilling to rely on "something like bear spray," he said. Advocates for carrying guns in bear country said spray can't stop a bear and that the spray would disperse in the wind without bothering the creature.

"Others say it'll just put you out and the bear will just have a seasoned snack," he said. "We wanted to see what the record would speak to."

The study examined 71 human-bear conflicts involving spray, as well as 11 incidents where people misused bear spray.

The misuse includes such mistakes as squirting the spray on tents or other camping gear, thinking it would work as a repellent. "They found out it actually attracted the bears."

Smith said the spray was 100 percent effective with polar bears, although there were only five incidents involving the great white carnivores. Among black bears, the spray was about 92 percent effective, and with grizzles, about 92 percent effective.

"It does turn bears, and it does buy you time to get away and resolve the situation," Smith said.