Elk fed amid concern about spread of chronic wasting disease

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JACKSON, Wyoming (AP) — 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.
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.
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.
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Source: eastidahonews.com