Why Biologists Are Looking To Capture Grizzly Bears in Yellowstone National Park

In the early 2000s, Grizzly 399, the big, fat, furry mom, gained celebrity fame for being the oldest bear to have reproduced four cubs. In 2001, a team of biologists tracked her down in the wild and used a dart gun to sedate her. Once she was sedated, they tucked GPS chips on her collar, and there began the game of research. These biologists, from the Interagency Grizzly Bear Study Team (IGBST), were curious to understand and decipher the mysterious biology of this warm-blooded bear mom.

And although the bulky mom passed away in the autumn of 2024, an 8-foot bronze statue perched on a pebbly cliff in Wyoming immortalizes her, as her cubs, now adults, roam around. She was one of the first bears to be collared for research. Recently, the National Park Service (NPS) rolled out a press release, announcing that biologists will now deliberately capture grizzly bears at Yellowstone National Park for research.

Yellowstone, the 22-million-acre ecosystem, is visited by millions of people worldwide each year. Tons of them come here especially to catch a glimpse of these hulking grizzlies feed on grass, hunt, mate, sniff, chase, and wrestle during the courtship rituals. According to the park service, an estimated 1,030 grizzly bears lived across 27,066 square miles of the Greater Yellowstone Ecosystem last year. And now these bears will be tagged and captured as part of a research initiative by the US Geological Survey. The goal, however, is not to hurt or harm the bears. The goal is to understand their biology and reproduction so their population can be recovered, as intended by the Endangered Species Act.

According to the NPS report, the IGBST biologists will capture the bears between September 1 and October 15. Once the bears are sedated and captured, the biologists will monitor their breeding, environmental impact, and travel routes. In an Instagram post, a researcher, Samantha Jolly Bervig (@jolly_bervig), shared that the capture of these bears becomes even more significant with the ever-growing change in the environment due to global climate change. “It’s more important now than ever to ensure we can maintain a stable population,” she noted.

The biologists will start the capturing process by luring and attracting the bears, primarily with food, including natural food sources like the carcasses of road-killed deer and elk. Potential capture sites will be baited with these foods. Once the bears are attracted to the food, the team will trap them in round pipe-like contraptions with sliding doors called “culvert traps” or use round foot snares to catch them by one of their paws. After the capture, the mammals will be sedated with tranquilizers, and then the biologists will examine them as well as fit radio collars to track their behaviors before releasing them back into the wild.

The USGS confirmed that once captured, the bears would be handled in accordance with strict safety and animal care protocols developed by the IGBST. Meanwhile, the park will adopt certain measures to ensure that the tourists know that this research is being conducted here. The area around the capture sites will be peppered with “bright warning signs” to warn visitors. Major access points will have markers, too. “It is critical that all members of the public heed these signs,” said the park service, and added, “Do not venture into an area that has been posted.”