State, Fed Biologists Warn Public To Stay Away From Grizzly Trapping Sites

Federal and state biologists are warning citizens to stay away from the bright orange "do not enter" signs where grizzly trapping is taking place. Bears that are recovering from tranquilizers may be "irritated" which could lead to a less-than-optimal encounter.

Mark Heinz

August 09, 20224 min read

Grizzly bear trapping sign scaled
(Cowboy State Daily Staff)

They aren’t “no trespassing” signs in the strictly legal sense, but venturing into the woods beyond one would still be ill-advised, because therein could be an irritated grizzly. 

Bright orange “do not enter” signs warning of grizzly bear live trapping and examination sties had been posted in remote areas near Yellowstone National Park earlier this summer.  They will continue to appear inside the park through October. 

Take Signs Seriously

There’s a reason those signs are there.

Take the case of Ewin Frank Evert of Cody, Wyoming. Back in June 2010, an adult male grizzly that had apparently just recovered from being tranquilized and examined by biologists at one of the sites attacked and killed Evert.

The attack occurred near Evert’s cabin along Kitty Creek in the Shoshone National Forest near Cody. Evert’s widow later unsuccessfully sued the federal Government, on the claim that the trapping and examination site hadn’t been adequately marked with warning signs beforehand. 

Tube-Like Metal Traps

The signs mark off areas where government biologists set baited live traps for bruins, in hopes of gathering data related to individual bears’ health, as well as insights into the vitality of the overall population.  

The U.S. Geological Survey’s Interagency Grizzly Bear Study Team and related agencies will use bait such as carrion to lure bears into large, tube-like metal traps.

They can be tranquilized for examination by biologists and then left alone to revive and go on about their grizzly business, which this time of year usually involves packing on fat for the upcoming hibernation season, according to the study team’s website. 

Still Going On In Yellowstone

The Wyoming Game and Fish Department wrapped up its trap-to-monitor program in areas outside Yellowstone this summer, large carnivore specialist Dan Thompson told Cowboy State Daily on Monday. 

Game and Fish finishes its trapping early in order to lessen the chances of conflict between grizzlies and hunters, firewood cutters and others who start venturing out during the late summer and autumn. 

The program will continue inside the park – where activities such as hunting and woodcutting aren’t allowed – until late October, Frank T. van Manen, a USGS ecologist and the study team’s supervisory research wildlife biologist, said in an email. 

The team typically traps and examines grizzlies inside the park “throughout the bears’ active season” which begins in April or May, he said. 

The exact locations of the trapping sites aren’t widely released to the public, to protect both the bears and people who might be foolhardy enough to venture into the sites, van Manen said. The sites are clearly marked with the warning signs at “all major access points.” 

Grizzlies Captured

Game and Fish this year captured seven grizzlies in the Sunlight Basin region and another six in Moccasin Basin, Thompson said. Of those caught and examined in the Sunlight area, two adult males, an adult female and young female were fitted with radio collars. All of the bears from Moccasin basin were collared, and included two adult males and four adult females.

“Capturing four adult females in one area is pretty significant, and they were all new captures,” he said.    

“Information from these collared grizzly bears provides data on survival, reproduction, distribution, habitat use, and movements of grizzly bears,” Thompson said. “In addition, some bears are not collared but samples obtained provide insight into genetics, diet, body condition.  Every animal handled provides a wealth of information for the overall population.” 

Radio collars provide a vital overview not only into the bears’ movements, but also provide insight into things such as mortality rates and the estimated number of females and cubs of the year, van Manen said. 

During the examinations, each bear’s size and weight is taken, along with hair and blood samples. The latter help biologists determine genetics and monitor the possible spread of disease, he said. 

Another vital measurement is body fat, he said. “Females need to enter the hibernation period with more than 20% body fat to successfully reproduce.” 

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Mark Heinz

Outdoors Reporter