Billings, Mont. ? Seven were hit by trains or cars. Ten were killed illegally, often shot and left to die. Thirteen were killed by wildlife officials because they had menaced humans or had otherwise become a nuisance. One was killed in self-defense.

All told, 31 grizzly bears in and around Glacier National Park in northwestern Montana, 18 of them female, died this year as a result of human actions. That’s the most of any year since the bears were listed as a threatened species nearly 30 years ago and nearly double the number killed in 2003.

While the number of deaths was unusually high, state and federal wildlife officials say it is not cause for alarm yet. They blame the rise in part on more people moving into bear territory and a poor berry crop that pushed more grizzlies out of the woods in search of food.

But some environmentalists are concerned, and not just about the grizzlies in and around Glacier National Park.

They also are worried about grizzlies around Yellowstone National Park, where run-ins with hunters accounted for nearly half the 19 grizzly bear deaths in 2004, and where a government proposal to drop federal protection for grizzlies could come as early as next year.

“I think we’re moving way too rapidly, given the warning signs on the horizon,” said Louisa Willcox, Wild Bears Project director for the Natural Resources Defense Council in Livingston, Mont. “We should take heed and slow down and really look at, and solve, the problems.”

Hunting and habitat loss contributed to the bears’ decline in the West early in the 20th century, and in 1975 grizzly bears in the lower 48 states were listed as threatened under the Endangered Species Act.

A grizzly bear is shown about four days after it died in August 2004 in Montana; the cause of death is unknown. Thirty-one grizzly bears in northwest Montana, 18 of them female, died this year as a result of human actions.

At that time, there were probably 200 to 250 grizzlies in the Yellowstone ecosystem, situated mostly in Wyoming. Today, the estimate ranges from 550 to 600, maybe more.

Chris Servheen, the U.S. Fish and Wildlife Service grizzly bear recovery coordinator in Missoula, Mont., calls those grizzlies “the greatest success in the Endangered Species Act.”