Wyoming News Exchange

Biologists study emergency sage grouse import to Jackson Hole
 
By Mike Koshmrl
Jackson Hole News&Guide
Via Wyoming News Exchange
 
JACKSON — An imperiled hot-button bird that’s an emblem of the West’s sagebrush steppe landscape is in dire enough straits in Jackson Hole that biologists are exploring an emergency import.
The valley’s population of greater sage grouse has always been relatively small, isolated and threatened, but when biologists and volunteers spread out across the landscape this spring they detected only half the number of strutting male birds they found a year earlier. A high of 40 male birds were tallied total at the valley’s eight breeding grounds, called leks. The population was the smallest since 1999, the previous historical nadir, and low enough that a spiral toward extirpation isn’t out of the question.
“We’re one good hatch year away from bouncing back,” retired biologist Joe Bohne said, “and one bad hatch year from the population teetering on the brink of extinction.”
Bohne spoke Tuesday at a meeting of the Upper Snake River Basin Sage Grouse Local Working Group. A last-resort translocation of birds to the valley was not on the agenda, though planning for that possibility as early as next year ended up consuming most of the four-hour gathering.
Wildlife managers, scientists and other working group members who attended said recent harsh, snowy winters have hurt grouse numbers. A dearth of available tall-sagebrush winter habitat owing to the 2003 Blacktail Butte Fire is another explanation for the continued decline, which has been ongoing since 2015.
“This year was 28 percent of normal,” said Leslie Schreiber, the Wyoming Game and Fish Department’s new statewide sage grouse biologist.
The historical average number of sage grouse counted within Wyoming’s designated “core area” in Jackson Hole is 167 males, she said. The total in the Snake drainage this spring amounted to 47 birds, though seven of the grouse were encountered strutting up the Gros Ventre River drainage at Breakneck Flats, home to an even more isolated and tenuous subpopulation that doesn’t show signs of mingling with grouse elsewhere.
Statewide sage grouse lek counts aren’t yet compiled, Schreiber said, but the tentative counts filtering in are either down or way down. Her predecessor, Tom Christiansen, told grouse managers in Cheyenne earlier this month that he foresees a possible “dark cloud on the horizon in terms of grouse numbers,” according to the news outlet WyoFile.
Wyoming is considered the last best stronghold of sage grouse, a species that’s been considered, but rejected, for federal protection under the Endangered Species Act. The Equality State had more than a third of the estimated 400,000 chicken-size birds that remained on the planet in 2015, owing to its 43 million acres of sagebrush, a shrub the species depends on.
Populations in the state are mostly contiguous, though mountain-encased Jackson Hole is an exception.
Based on past genetics work, the sage grouse that remain in the valley are genetically distinct — as distinct as Gunnison sage grouse, which is deemed its own species. Teton Raptor Center research director and working group member Bryan Bedrosian said inbreeding coefficients in the population are “high.” Among the few sage grouse that linger up the Gros Ventre, they are “astronomical,” he said.
“There’s a good chance that this won’t work,” Bedrosian said, “but increasing our diversity can’t be a bad thing.”
At times in the past — most recently in the late 1990s — the population has pulled through bottlenecks.
Wyoming officials have tried in the past to ship sage grouse into the valley. Rather than kill nuisance alfalfa-eating grouse in the Farson area, biologists instead released them in Jackson Hole in 1948 and ’49, according to the Snake River working group’s 2014 conservation plan. Before the midcentury translocation, the estimated population in the valley was 500. Based on lek counts the following years and where the banded birds turned up, the sage grouse didn’t stick around. Bohne espoused pulling birds from the same area, which today still cause damage to private agricultural fields.
Modern-day efforts are underway using translocation to stave off sage grouse extirpations in places like North Dakota and Nevada. Managers are experimenting with techniques using younger transplanted birds, including hens with just-hatched broods. A partnership underway between Wyoming and North Dakota is relocating birds from the Rawlins area. Before the project started, the Peace Garden State’s population dwindled to just seven strutting males, Schreiber said.
So far, Schreiber reported, the Wyoming transplants have been prone to taking off for Montana and falling victim to birds of prey.
Before launching into the discussion about moving grouse to Jackson Hole, the working group reviewed a 2017 memorandum of understanding between Wyoming and the federal agencies that manage grouse and their habitat. The “adaptive management plan” includes “hard” and “soft” triggers that direct managers to take steps to conserve sage grouse.
Because Jackson Hole’s grouse numbers have dropped more than 60% below their normal historic population, the decline in the valley has already tripped the soft trigger.
The “hard trigger,” considered a “catastrophic indicator” that a population isn’t responding to conservation, would be tripped when there has additionally been the total loss of leks or a significant loss of habitat.
Bedrosian made the case that this threshold has also been met.
“I would argue that this year Spread [Creek Lek] is gone,” he said. “I would argue that Bark [Corral Lek] is gone.”
A single male bird was counted at each Grand Teton National Park lek this year, down from 10-year averages of nine birds at each.
As of last year the National Elk Refuge’s McBride lek was officially recognized as unoccupied, Bohne pointed out. He surmised that early morning traffic headed down Highway 89 to places like Jackson Hole Airport caused its long-term decline, because sage grouse need quiet spaces to perform their mating rituals and attract mates.
Because the 2017 MOU is geared toward multiuse Bureau of Land Management property, Grand Teton National Park wildlife biologist John Stephenson encouraged the working group to come up with its own management responses to population declines. The valley’s grouse are largely tied to intact and protected sagebrush expanses in the park, though harsh winters tend to scatter birds around the valley.
Stephenson and Bridger-Teton National Forest biologist Jason Wilmot walked away from the meeting committed to checking with the powers that be about attitudes toward a translocation project, and what it would take to get one authorized.
“I don’t think we’re making that decision here today by any means,” Stephenson said. “That is a long process.”
Such an operation will likely require some level of National Environmental Policy Act analysis, which is a public process that includes gathering public input.
Working group members discussed bringing in outside experts for a symposium later this summer, such as geneticists and managers who are actively dealing with transplanting sage grouse.
There was also talk of gathering information about other, less likely techniques used to help sage grouse, such as killing predators like ravens.
Talk of translocating grouse was nuanced enough that working group members touched on topics like how they would pay for GPS devices to monitor the relocated birds and what type of technology they’d go with.
Tracking backpacks could be bought and sit on the shelf and then be promptly deployed on imported grouse if next year’s lek counts are even bleaker, Schreiber said. If numbers are up, she said, they could be used for more routine research on existing birds.
“If we’ve got 10 birds in Jackson Hole,” Schreiber said, “we’d better be ready to do something.”
Bedrosian had a similar assessment: “Let’s plan for disaster and hope for the best.”