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Jackson Hole, WY News

CWD and concentrated elk: The experiment begins

Status quo is continuing for now as thousands of elk head toward hay and alfalfa for the winter.

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Elk feeding on the National Elk Refuge

Elk congregate during feeding operations on the National Elk Refuge. The refuge has entered a new phase of challenges after a cow elk harvested in nearby Grand Teton National Park tested positive for chronic wasting disease, a fatal illness that spreads easily when animals are concentrated.

Wildlife managers are forging into uncharted territory as they keep feeding elk in the southern Greater Yellowstone Ecosystem while knowing that concentrating thousands of animals on feed will likely exacerbate the spread of the fatal chronic wasting disease.

For the first time biologists also have detailed data showing just how bunched up elk are on northwest Wyoming’s historic feedgrounds as a result of doling out alfalfa pellets and hay during the harshest months of the year.

“Basically, elk contact rates were 2.6 times higher during the feed season,” National Elk Refuge Senior Biologist Eric Cole said. “During feeding operations themselves — when elk are actively being fed — we commonly have elk in densities of 1,000 elk per square kilometer.”

Comparing densities of unfed versus fed elk — results will be published soon in an academic journal — was possible due to the mild winter of 2017-18. That year virtually the entire 11,000-animal Jackson Herd wintered on the refuge when a near total absence of low-elevation snow negated the need for supplemental feed. Cole analyzed GPS data from dozens of elk adorned with tracking collars, deeming “close contact” to be any instance when two tracked animals came within 500 meters of each other.

Snow depth was also a determinant of density, but it had just half the effect of feeding.

“Feeding by itself,” Cole said, “is definitely the strongest predictor of elk contact rates.”

Cole’s analysis was restricted to about 15,000 acres on and near the U.S. Fish and Wildlife Service refuge bordering Jackson — a much vaster landscape than all of the 22 elk feedgrounds run by the state, where elk are fed in even tighter quarters.

The new density data adds nuance to what wildlife managers have long known: that feeding concentrates animals, creating a conduit for the transmission of diseases that can cause elks’ hooves to rot, like necrobacillosis, or cause cows to abort their first calves, like brucellosis.

Top 10 stories of 2020

Carl Brown, center, a National Park Service wildlife disease technician, removes the lymph nodes from a hunter-killed cow elk for chronic wasting disease testing in Grand Teton National Park in November. An elk killed Dec. 2 in the park was found to have contracted the deadly disease.

Now another disease, this one 100% lethal, has been confirmed for the first time among the Jackson Elk Herd, which has historically relied on feedgrounds. A lymph node from a cow elk shot by a Wyoming resident in Grand Teton National Park in early December tested positive for CWD repeatedly, meaning the presence of the incurable prion disease in Jackson elk is now official.

“This is ushering the National Elk Refuge into a new era,” Refuge Manager Frank Durbian said. “There are going to be some changes, there are going to be some challenges and probably some things affected that we haven’t even predicted.”

In the decades leading up to CWD’s arrival on elk feedgrounds, environmentalists and wildlife scientists have been calling for a halt to the century-old system out of concern for how feeding might accelerate spread of the fatal brain-wasting disease.

With the disease now here, federal and state agencies have either modestly adjusted operations or just started examining possible changes to curb disease transmission. About 20,000 elk are fed on the federally-managed refuge and on 22 state-run feedgrounds in Teton, Sublette and Lincoln counties.

The state feedgrounds are the subject of an ongoing planning process that will culminate in a new management plan and perhaps some long-term adjustments. That effort, however, was set up from the onset with the aim of keeping the feeding system intact.

“There’s no real potential to really change feeding operations in the short or the mid-term,” Wyoming Game and Fish Department Director Brian Nesvik said during a legislative committee meeting Dec. 8. “This is not a proposal to close feedgrounds.”

Nesvik described elk feeding as a “wicked problem” with no straightforward solution. Feedgrounds have persisted largely unchanged because they’re used as a tool to keep elk off private land and away from ranchers’ hay stacks, where elk risk spreading the disease brucellosis to cattle. The supplemental winter nutrition has also continued for decades because it helps maintain higher elk populations in areas where low-elevation winter ranges are now occupied by human development.

CWD lymph node

One of two lymph nodes extracted from a hunter-killed cow elk in Grand Teton National Park in December 2018. The lymph nodes are used to test animals for chronic wasting disease.

Taking jabs and positions on elk feeding’s merits “aren’t really productive, at this point,” said longtime Greater Yellowstone Coalition employee Chris Colligan. But he added that it’s wrongheaded of the state to launch into its process with a predetermined outcome. When Game and Fish started its feedground review late in November, CWD on the feedgrounds was still a hypothetical and there was still an opportunity for proactive planning.

“Now, our reality is here,” Colligan said. “I think it’s reckless to start with the position that ‘We’re not going to change anything with feedgrounds in the immediate future.’”

Around North America wildlife managers are grappling with how to respond to an always-fatal disease that persists in the environment outside of animal hosts and, in places, is causing deer and elk populations to decline. For years Wyoming has been viewed by other states as the do-nothing control for CWD because the Equality State’s wildlife officials were monitoring the prion disease’s spread but not doing much more. Continuing a passive response to see what’s going to happen at the feedgrounds is untenable in the eyes of Colligan, a former Game and Fish employee and disease specialist.

“I think to do that on elk feedgrounds has a potential for disaster,” he said. “Our economy and identity in western Wyoming is associated with elk populations. Just to do nothing in light of this discovery shouldn’t be an option.”

Elk managers do have some insight into what’s likely to come for the seven feedground-dependent herds that dwell in Teton, Sublette and Lincoln counties.

In the Laramie Peak herd, which roams where elk are not fed and CWD has been on the landscape for decades, prevalence has bounced between 5% and 10%, low enough to allow the herd to grow while allowing hunting. But just to the south in the Iron Mountain Herd, Game and Fish Wildlife Disease Supervisor Hank Edwards is starting to see more and more CWD.

“Last time we did an intensive survey, we were at about 16%,” Edwards said. “Every herd is different.”

In Rocky Mountain National Park, another place where CWD has been around for years among unfed elk, researchers have found that populations decline once prevalence tops 13%. But where wapiti are being fed on the National Elk Refuge, Cole pointed out, densities of animals are an order of magnitude — tenfold — greater than they are at the Colorado national park.

It’s “anybody’s guess,” in Edwards’ view, how the spread of CWD is going to play out in the feedgrounds, although his prediction is that the elk face tough times ahead.

Ungulate classification

Elk congregate on a feedline as a tractor spreads supplemental alfalfa pellets on the National Elk Refuge. Managers counted 8,095 elk on feed during a Feb. 18, 2020 refuge count.

“This is not going to be good. That’s my gut feeling,” Edwards said. “But we certainly can’t say let’s just close the feedgrounds today.”

It was Edwards who made the phone call to the hunter who shot a cow in southern Grand Teton National Park on Dec. 2. At the time a park technician extracted a lymph node, which later repeatedly tested positive for CWD at Wyoming’s Wildlife Health Laboratory. The man, he recalled, was both “very bummed out” and surprised.

While a single positive test doesn’t say a lot about CWD’s current prevalence among the 11,000-animal Jackson herd, Cole said the data point is useful. Based on the 450-plus CWD samples that were collected within the herd this hunting season there might be somewhere in the neighborhood of 0.2% prevalence, he said.

“There’s anywhere from one [positive], and we killed it, up to 50,” Cole said. “Most likely it does only exist at trace levels, and that’s fortunate for us because it does give us some opportunity to institute some mitigation before the effects get serious in the population.”

Ecologists have taken cracks at what’s likely to happen from here. In 2017 research led by Colorado State University and supported by Cole and Wyoming Game and Fish’s Doug Brimeyer predicted that prevalence would reach 10% within five years of CWD’s arrival. That exceeds the most probable tipping point that will trigger a declining population, which was 7% in the Jackson Herd.

Tom Hobbs, one of the authors, cautioned when the study was released that the model did not take into account the effect of the unnaturally high concentrations of animals on the refuge.

“The densities on the refuge are unusually high, and you really have got no precedent for this,” Hobbs told an audience at a Jackson Hole CWD forum. “Animals do return to the same place year after year after year, much more than any population that has been studied.”

CWD reaches Jackson Hole elk

Chronic wasting disease biologist Aaron Morehead picks up a load of elk heads from Jackson’s lone game processor to return to Wyoming Game and Fish Department offices for lymph node extraction in December 2018. Game and Fish stepped up efforts to test for the disease after it was discovered in a mule deer killed by a car in Grand Teton National Park in late November of that year.

The modeling exercise suggests big near-term changes to hunting in the valley because the population’s predicted 7% prevalence tipping point figures an absence of cow elk harvest. For almost all of its history the Jackson Elk Herd has been intensively hunted late into the year, with cows and calves targeted to check the population.

Cole said it’s unlikely that hunting on the refuge is going away anytime soon. The management tactic is used to keep elk off the refuge, for one, which allows forage to stay in the ground and the refuge to delay feeding for longer. The elk density research soon to be released also identifies hunting pressure as a successful tool to disperse elk and reduce contact rates, he said.

There’s also a chance the Jackson Herd will be hunted down to a smaller size. The National Elk Refuge’s chronic wasting disease response strategy calls for both reducing reliance on supplemental feeding and working with Game and Fish to revisit the population goal for the Jackson Herd, which has sat at 11,000 since the refuge, Grand Teton National Park and the Bridger-Teton National Forest wrapped up a decade-long federal planning effort in 2007.

The policy that emerged, dubbed the bison and elk management plan, calls for 5,000 elk on the refuge, a figure that’s theoretically supposed to allow the refuge to do without supplemental feed in an average northwest Wyoming winter. Numbers, however, have consistently exceeded that objective, as the Jackson Herd has become more reliant on the refuge than in any other time in its history.

The refuge’s blueprint for achieving that goal is detailed in a secondary “step-down” plan that was released late in 2019 as a result of a court agreement after a yearslong delay. The plan, which is now being litigated, calls for shortening the feeding season, initially on the back end in the spring and then starting in 2022 by delaying daily lines of alfalfa until later into the winter. Having a shorter feeding season won’t reduce elk densities, but Cole said it does reduce the overall chance of transmission.

There are other steps that Game and Fish and the refuge are taking that aim to reduce transmission. Surveillance for sickly looking elk at the state and federal feedgrounds has been dialed up. When an animal is identified with signs of CWD, like listlessness and emaciation, it’s promptly killed, tested and its carcass moved away. The refuge is also looking at ending its traditional carcass dump site and adding an incinerator capable of temperatures that destroy infectious prions, the vector of CWD.

Youth Elk Hunt

Victor Ochoa, of Rawlins, quarters a bull elk shot by his daughter, Adriana, as Aly Courtemanch, a Game and Fish wildlife biologist, observes during the final day of the youth elk hunt at the National Elk Refuge last month. Hunting figures into the overall strategy to reduce the number of elk on the refuge over the winter from about 11,000 down to 5,000 animals.

Like the refuge, Game and Fish is also abridging the feeding season, Regional Supervisor Brad Hovinga said. His feeders have also been instructed to distribute hay in ways that lead to lower-density congregations.

There are supporters of managers’ decision to move incrementally in response to CWD reaching the feedgrounds. Sy Gilliland, president of the Wyoming Outfitters and Guides Association, said he will fight to ensure elk are still fed, even if it increases the chance they contract a disease with no vaccine and “no hope on the horizon.”

“We’ve made a home for these elk so that we don’t see these massive die-offs,” Gilliland said. “I don’t think that Wyoming citizens are going to stand by and let these elk starve to death, it’s not going to happen.”

Colligan, at the Greater Yellowstone Coalition, said he doesn’t buy the starvation argument. Elk won’t just starve but instead seek food in places where they’re not tolerated, like ranches and neighborhoods.

“We don’t accept elk distribution on the landscape like almost every other place elk exist,” he said. “All the reasons listed for feeding elk have solutions.”

Some groups are using the courts to force changes that would diminish the chances the National Elk Refuge and state feedgrounds would increase the severe effects of CWD.

One pending lawsuit targets transmission risks posed by the degenerative disease on the Dell Creek, Forest Park and Alkali Creek feedgrounds, which are run by the state but located on the Bridger-Teton National Forest.

Earthjustice, representing the Sierra Club, National Wildlife Refuge Association and Defenders of Wildlife, is also challenging the refuge’s step-down plan. The discovery of an elk with CWD in the Jackson Herd is not changing what attorney Tim Preso will be asking of a U.S. District Court judge in Washington, D.C., he said.

“It’s never been our intention for the service to stop feeding cold turkey,” Preso said. “A weaning process is required, but we could have been starting that weaning process 13 years ago. Instead we let more than a decade go by to reform the feeding program and now we’ve got CWD in elk and mule deer in Jackson Hole.”

Gros Ventre Elk Feedground

Lucas Bielby and Jay Hoggan drive their team out to feed elk in 2017 on the Patrol Cabin feedground in the Gros Ventre River drainage.

Contact Mike Koshmrl at 732-7067 or

Mike has reported on the Greater Yellowstone Ecosystem's wildlife, wildlands and the agencies that manage them since 2012. A native Minnesotan, he arrived in the West to study environmental journalism at the University of Colorado.

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