Two yearling grizzly bear carcasses were discovered by Grand Teton National Park staff in the Colter Bay area on May 13. The bears showed signs of depredation by a larger bear, according to a park release.
Upon patrolling the area, law enforcement and wildlife staff observed a lone adult grizzly bear that they identified as grizzly day 1063. This female bear has been observed earlier this season with three yearling cubs. No cubs were observed with her during this sighting.
Based on observed behavior and evidence, park staff deduce that a male grizzly bear in the area led to the separation of the yearlings from their mother and was responsible for their deaths. The status of the third yearling remains unknown.
“Bears exhibit a range of fascinating behaviors influenced by their biological needs, social structures and environmental factors,” said Grand Teton National Park bear biologist Justin Schwabedissen. “While it is incredibly sad to see a grizzly bear lose its cubs, depredation by other bears is a natural source of cub mortality in the Greater Yellowstone Ecosystem and has previously occurred in Grand Teton.”
Grizzly bear management
In recent weeks, GB1063 and her cubs had been observed in and around developed and residential areas at Colter Bay. At times, it was necessary for park staff to “haze” the bears. This practice is a management tool that protects bears and humans when bears linger in one area. A wide array of tools and tactics are used to scare the bears away from areas where they might become hurt or inflict harm. Each time hazing was implemented, GB1063 and her cubs remained together, according to the release.
Park staff continue to monitor the area and remind visitors to remain bear aware: carry bear spray, maintain a safe distance from all wildlife, and report any bear sightings to a park ranger.
Earlier this season, one of Grizzly 399’s cubs was struck and killed by a vehicle in Grand Teton NP.
