A 10-year-old male grizzly bear with a history of killing livestock was euthanized this weekend after it was captured for killing cattle southeast of Red Lodge.

The 400-pound bear was caught in a culvert trap Friday by federal Wildlife Services agents on the Sunlight Ranch near the upper forks of the Bearcreek Basin.

"It was never seen," said Shawn Stewart, a Montana Fish, Wildlife and Parks wildlife biologist based in Red Lodge. "We finally saw tracks and hair on a fence so we knew that we were dealing with a grizzly bear."

Wyoming officials captured the bear in 2007 north of Cody after it killed cows in that area. They put a microchip and lip tattoo in the animal for future identification and released it west of Dubois, Wyo., about 90 miles southwest of Cody.

The bear apparently traveled north through the Yellowstone area and into Montana this year, Stewart said. After reports of livestock depredation near Red Lodge, federal agents spent about 10 days trying to capture the bear. Stewart said it had killed at least three cows and two calves. Other cattle deaths at the ranch couldn't be confirmed as bear kills.

Because the bear was a two-time offender, biologists decided to euthanize the animal.

Stewart said the bear appeared to be in average shape for this time of year, although it had one chipped canine tooth and another broken one.

Bears along the eastern face of the Beartooth Mountains are not uncommon, but their numbers seem to be growing.

"There's definitely more grizzly activity around here more of the time," Stewart said. "They seem to be working up that east face of the Beartooths from Wyoming."

Clark, Wyo., to the southeast of Red Lodge just over the Montana border, has seen its share of grizzly bears over the past few years, partly because of its landfill that takes dead livestock. Several bears frequenting the area have been trapped and relocated. In July 2009, a Clark-area man was mauled while walking through sagebrush while scouting for elk. He shot the bear. This year, two men have been killed by grizzly bears in Yellowstone National Park.

The Interagency Grizzly Bear Study Team has recorded 25 grizzly mortalities in the region so far this year out of a estimated population of about 600. That 25 includes three cubs that have been orphaned after their mother was killed in an incident under investigation in Wyoming's Shoshone National Forest. Orphan cubs are counted as mortalities because they aren't expected to survive the winter without their mother.

Overall, food sources for bears entering the fall season are good in the Red Lodge area and east of the Continental Divide in Wyoming. Stewart said whitebark pine cone sites he surveys along Rock and Line creeks showed an average of more than 100 cones per tree, which he called "downright excellent." That compares to an average of about 20 per tree across the region.

Stewart said chokecherry tree production is spotty in some places near Red Lodge after a heavy hail storm stripped some trees of berries. Some of the berries were about three weeks late to mature, too, because of the cool early summer. Last year, in comparison, was a poor year for vegetation, Stewart added.

Grizzly bears are listed as a threatened species, a designation that is under litigation.