POWELL — As news of translocations of two grizzly bears broke, few realized the amount of hard work — on the phone, on paper and in the wilderness — it takes to make such a feat happen.
It is touted as a step to increase genetic diversity in the Greater Yellowstone Ecosystem’s population of its most charismatic creature. But if you think all they had to do was load a couple bears in a truck and drive six to eight hours to release them in and near Yellowstone National Park, you’d be wrong.
The Wyoming Game and Fish Department’s large carnivore team worked with its counterparts in the three states with appropriate grizzly bear habitat to develop the protocols and work through logistics, as well as the actual release in Wyoming.
The translocations were the result of a commitment between Wyoming, Montana and Idaho under the Tri-State Memorandum of Agreement. The agreement was established to ensure the long-term genetic diversity of the GYE’s grizzly bear population and secure a genetic connection between the two areas, according to a release by Wyoming Gov. Mark Gordon.
The bears, a subadult female and subadult male, were captured in a remote portion of northwest Montana by Fish, Wildlife and Parks employees and transported “safely and securely” to Wyoming, where the large carnivore team received the female and Yellowstone National Park received the male.
On July 30, Wyoming’s large carnivore team released the sow in the Blackrock drainage, approximately 35 miles northwest of Dubois.
The following day Yellowstone National Park personnel released the male within park boundaries, in a remote area south of Yellowstone Lake.
“This very much was a collaborative success,” said Dan Thompson, large carnivore supervisor for the Game and Fish Department. “The occasional introduction of new genetics will provide some long-term benefits to the species.”
It started with developing a long-term plan and seeking approval, he said. With the plan finally ironed out, the governors of Montana and Wyoming approved the project along with officials from the National Park Service.
“Bear managers in the three states plus managers from multiple federal agencies, worked cooperatively to develop the translocation plan,” Thompson said.
Yellowstone National Park has been one of multiple state and federal agencies involved in developing the Conservation Strategy for Yellowstone Grizzly Bears, an effort that began in the 1990's, and the park has been involved in discussions concerning the potential need for genetic augmentation and connectivity with the NCDE for several decades, according to Yellowstone’s Bear Management Biologist Kerry Gunther.
“Because several scientific studies have indicated some loss of genetic diversity in the GYE as compared to the NCDE, the states of Montana, Wyoming and Idaho proposed a genetic augmentation program be implemented in 2024, in addition to ongoing efforts to enhance on the ground connectivity between the two populations,” Gunther said.
Park Superintendent Cam Sholly, who has always been a strong supporter of grizzly bear conservation, personally offered the park as one of the recipients of the translocated bears.
Just the beginning
This will not be a one and done project, according to Frank T. van Manen, supervisory research wildlife biologist for the U.S. Geological Survey’s Interagency Grizzly Bear Study Team.
A general rule in conservation genetics for grizzly bears is that one or two effective migrants that successfully breeds and whose offspring survive to adulthood per generation (one generation is about 14 years) is sufficient to alleviate long-term genetic risks to the population, he said in an interview with the Tribune.
“In theory (increasing genetic diversity) would not require a lot of translocations, as long as these bears survive and breed. Of course, some bears may not survive and it is anticipated that about three to six bears per generation might be needed to achieve this objective,” van Manen said.
The current plan is to translocate one to two grizzlies approximately once every 10 years from the NCDE to the GYE.
This may be modified in an adaptive management process based on the best available scientific knowledge of genetics as well as the survival and successful breeding by the translocated bears.
Because the NCDE already has genetic connectivity with occupied grizzly bear range in Canada, there are not currently any plans to move GYE bears to the NCDE, according to Gunther.
The interagency team will be documenting whether the genetic augmentation is successful using a two-fold effort. First, it plans to monitor whether the translocated bears are staying in the targeted area and survive, which is accomplished through telemetry monitoring and will follow standard monitoring procedures used by the Interagency Grizzly Bear Study Team.
“Of course, we will pay particular attention to these two individuals, but in principle they will be monitored like all other radio-marked bears,” van Manen said.
The bears were fitted with GPS satellite radio collars. The satellite acquires a fix of the bears’ location every 3.5 hours and then downloads the data to biologists once every two days. The bear's collar also emits a vhf telemetry signal that can be monitored from the ground or fixed-wing aircraft providing a secondary method of monitoring the bears.
To monitor survival, the collars also have an activity sensor that will alert biologists if the collar stops moving, indicating one has either dropped off of the bear or that one of the bears is dead. Biologists would then investigate the collar's final location on the ground.
Breeding is key
The second component is to document whether these two subadults will ultimately breed, thereby introducing new genetic material into the Greater Yellowstone Ecosystem population.
The study team accomplishes this objective through standard genetic monitoring — by collecting hair or tissue samples of any bear that is captured in the ecosystem, as well as samples from mortalities and occasional targeted DNA sampling efforts.
This genetic evidence will likely require some time and involves some chance events: these bears need to mate first, their offspring would need to survive, and have a chance to be sampled. That will take years, van Manen said.
“Once we obtain a sample, we won't know the origin until it is analyzed by a genetics lab. All in all, that could cover a time span of four-to-five years or more,” he said.
The male bear released in Yellowstone was estimated to be 4 years old, so he should be sexually mature and capable of breeding by next spring's breeding season, Gunther said.
However, his chance to breed will depend on his size, aggressiveness, fighting ability and ability to locate females in estrus. He will be competing against prime age males and will likely be most successful at competing for females when he gets a little older, more experienced, and larger in body size.
“His peak period of breeding will likely be from ages 8 to 12 years old. Therefore, this bear likely still has two and a half years before he becomes a major contender for adult females. How much genetic diversity he adds to the population will depend not only on his fighting skill, size, and aggressiveness, but also on how long he survives,” Gunther said.
There is plenty of time for the translocations to take effect because, based on the federal government studies, the genetic status of the population is not an immediate concern, van Manen said.
Based on data analyzed from 1985 through 2007, the rate of inbreeding has been very low since 1985, and no effects that might be associated with inbreeding have been detected.
The genetically effective population size (basically the number of bears contributing genes to the next generation) has increased as the population recovered and is well above the level needed to prevent short-term impacts, such as inbreeding, he said.
By 2007, the ecosystem was close to levels needed for longterm genetic viability.
Genetic connectivity
Despite the scientific evidence that genetic connectivity is not an urgent concern for the population, it was one of the three primary considerations in the court rulings and litigation that followed the 2017 delisting, which focused on a lack of "regulatory mechanism"; the commitment to genetic augmentation specifically addresses that issue, according to the Interagency Grizzly Bear Committee’s 2024 Conservation Strategy.
The court decision on the 2017 relisting rule called for the states to commit to translocation of grizzly bears to support genetic fitness in the absence of natural connectivity with other grizzly bear populations.
If effective migration fails, the states will continue to make additional translocations from outside the region while genetic samples are collected from all grizzly bear captures and mortalities in the GYE. These samples – in addition to genetic samples acquired from rub trees or other methods – will be analyzed via cooperative efforts between the Interagency Grizzly Bear Study Team and genetics experts.
“The states’ commitment is consistent with this direction,” according to the report.
In the meantime, the potential for genetic connectivity through natural movement continues to improve and may be imminent as well or might have occurred already; the distance between occupied range of the Greater Yellowstone and the Northern Continental Divide Ecosystems is now about 60 miles, which is within a boar’s dispersal distance, and there are now numerous verified records of bear presence in areas in between.
Traveling grizzlies
It will be interesting to see if the bears follow the timeline of a 2022 study led by Canadian wildlife biologist Gordon B. Stenhouse, researching the species’ response to translocation into new environments after conflicts.
The study investigated differences between these groups in relation to exploration behavior, habitat use and response to human-caused mortality risk.
Translocated bears had higher movement rates, greater daily displacement and revisited areas less frequently than did resident bears. They spent more time in poor-quality habitat and the habitat used was lower quality in the second year after translocation.
“Translocated bears selected agricultural lands and active oil and gas well sites. They also spent more time in areas with higher potential mortality risk than resident bears,” according to the published results.
However, so far most translocated bears avoided fewer residential areas than resident bears selected and crossed roads at the same rate as did resident bears.
Both groups avoided campgrounds and recreation sites. Only 25% of bears engaged in further conflict behavior after translocation and 67% of translocated bears survived over the two-year monitoring period.
“Despite all the research, we will likely never know everything about the lives of bears,” Stenhouse said in a 2021 interview with Michelle Cyca of Maclean’s magazine.
Despite all the hard work, there is criticism of the plan.
Those opposing delisting the species have said translocations are proof that they are not yet ready for delisting. Yet these translocations addressed concerns brought up through lawsuits challenging the U.S. Fish and Wildlife Service’s 2017 delisting rule despite there currently being no immediate concerns with the genetic health of GYE grizzly bears, Thompson said.
“There will always be those who will look for reasons to keep bears perpetually listed and we continue to demonstrate our capacity to manage this species responsibly,” he said.
Wyoming spends a big bucket of money on the species.
While the U.S. Fish and Wildlife Service provides a small amount of grant money to Wyoming that is used to pay for some aspects of grizzly bear management, Wyoming is footing the bulk of the bill (more than $2 million per year) while not being able to have state management authority for the species, Thompson said.
Otherwise, it is business as usual for the large carnivore team.
Soon they’ll be on high alert heading into the species’ hunt for calories prior to hibernation, known as hyperphagia. In the coming months, the team will be focused on conflicts, which are likely to increase as hunters start entering the backcountry.
Time will tell if the translocated bears can stay out of trouble and survive long enough to make a difference.
The Game and Fish bear-wise page is a good resource for the public, providing information and education on bear safety.
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