BILLINGS, Mont. (AP) — Environmentalists want the government to study whether a federal agricultural research station on the Montana-Idaho border is harming the region's protected bear population after a collared grizzly bear disappeared from the area.

John Meyer with the Cottonwood Environmental Law Center said Thursday that his group will seek to shut down grazing on 16,000 acres at the U.S. Sheep Experiment Station at Dubois, Idaho, if the government does not take action. The 392-pound male bear was being tracked by researchers when it disappeared last August from sheep station property.

Its collar was later found under a rock in a creek. A single bullet cartridge was discovered near where the bear was last detected by researchers. An investigative report obtained by Meyer's group through the Freedom of Information Act was inconclusive.