The National Park Service (NPS) has an important message for everyone visiting Yellowstone National Park this fall.
“Heed warning signs,” the NPS urges visitors.
Biologists for the “Interagency Grizzly Bear Study Team” (IGBST) have begun capturing grizzly bears in the field as part of the ongoing effort to monitor the bears’ population in the Greater Yellowstone Ecosystem. They will continue capturing select grizzly bears through October 31.
The biologists use natural food sources such as fresh road-killed deer and elk as bait to attract and then capture the bears using culvert traps and sometimes foot snares. Once captured, the bears are, of course, handled following strict safety and animal care protocols developed by the IGBST and approved by the U.S. Geological Survey and the NPS.
“Whenever bear capture activities are being conducted for scientific purposes, the area around the site will be posted with bright warning signs to inform the public of the activities,” the NPS explains. “These signs are posted along the major access points to the capture site. It is important that the public heed these signs and do not venture into an area that has been posted.”
Grizzly Bears In The Region
Northwest Montana and the Greater Yellowstone Ecosystem — including Yellowstone National Park and sections of northwestern Wyoming, southwestern Montana, and eastern Idaho — are the only areas south of Canada that still have large grizzly bear populations. While an estimated 1,063 grizzly bears were believed to be in Greater Yellowstone in 2021, only 150–200 are believed to have a home wholly or partially in Yellowstone, according to the NPS.
Amazingly, grizzly bears are generally 1.5–2 times larger than black bears of the same sex and age, the NPS explains. Males can weigh up to 700 pounds while females typically weigh 200–400 pounds.
Grizzly bears, which may live 15–30 years, can run at up to 40 miles per hour. While they are able to climb trees, their curved claws and weight make it difficult.
An Interagency Effort
The IGBST is an interdisciplinary group of scientists and biologists responsible for long-term monitoring and research efforts on grizzly bears in the Greater Yellowstone Ecosystem. The team was formed by the Department of the Interior in 1973.
It’s important to note that the team is made up of personnel from the U.S. Geological Survey, NPS, U.S. Fish and Wildlife Service, U.S. Forest Service, Eastern Shoshone and Northern Arapaho Tribal Fish and Game Department, and the states of Idaho, Montana, and Wyoming. Working together ensures consistency in data collection and also allows combining limited resources.
The main objectives of the team are to monitor the status and trend of the grizzly bear population in the Greater Yellowstone Ecosystem. Secondly, they aim to determine patterns of habitat use by bears and study the relationship between land management activities and the welfare of the bear population.
To do that, the IGBST focuses on three key activities.
The first is to identify and document the abundance and distribution of female grizzly bears with cubs born that year, which provides a good indication of whether or not the overall grizzly population is growing.
The team also applies radio collars on individual bears so the bears can be monitored, which provides critical information including average litter size, cub and yearling survival rates, how often a female produces a litter, and causes of mortality.
The final activity is to monitor the seed production of whitebark pine trees. Those seeds are a high-calorie food resource for grizzly bears in the late summer and fall so it’s important to learn about seed availability.
You can learn more about grizzly bear research and monitoring at the IGBST.
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