In a grim milestone, Chronic Wasting Disease documented in two Idaho mule deer

Two Idaho mule deer bucks have tested positive for Chronic Wasting Disease, according to the Idaho Department of Fish and Game. This is the first time the deadly neurological disease has been documented in Idaho.

The bucks were killed in October in the Slate Creek drainage near Lucile, which is south of Grangeville on Highway 95. The samples were tested at the Colorado State University Veterinary Diagnostic Lab and are being verified by the National Veterinary Services Laboratories in Ames, Iowa, according to an agency news release.

Anyone hunting in Unit 14 is encouraged to have any harvested deer or elk tested. To sample for CWD, lymph node tissue from fresh or frozen harvested heads are extracted. Meat or muscle tissue cannot be used to test for CWD.

Per IDFG’s CWD strategic plan, both hunters have been notified that their bucks tested positive. Now, officials are planning the agency’s next steps, said spokesman Roger Phillips.

“It’s something obviously we’ve been taking very seriously,” said Panhandle regional spokesman T.J. Ross. “Early detection is really important. We don’t know what it means for the population in Idaho at this point. I think that’s why we are taking it seriously and why we are approaching it cautiously.”

Although CWD has been known to exist in the Western United States for more than 40 years, this is the first time animals in Idaho have tested positive for the disease, which is fatal to deer, elk, moose and caribou. The Idaho Fish and Game Commission has been notified, as well as the Idaho Department of Agriculture, the Idaho Department of Health and Welfare and the U.S. Department of Agriculture, according to the release.

CWD was first documented in Fort Collins, Colorado, in 1967. With the confirmation of CWD in Idaho it has now spread to at least 26 states and two Canadian providences. Earlier this year, it was documented in the Teton Wilderness and Greys River watershed, a world-class hunting area in Wyoming south of Yellowstone National Park.

In 2019, it was confirmed in whitetail deer near Libby, Montana, just miles from the Idaho border. CWD can decimate wild ungulate populations. According to a University of Wyoming study CWD can kill up to 19% of a population annually.

Since the 2019 confirmation in Libby, IDFG officials in the Panhandle Region have sampled for CWD yearly. IDFG has sampled for CWD in different areas of the state since 1997. On average, the Gem State spends about $100,000 per year on its CWD detection efforts. In 2018, Idaho banned the importation of deer, elk or moose carcasses from areas with CWD.

As of August, IDFG had tested 1,113 mule deer, whitetail deer, elk and moose samples. Those samples were collected in 2020 and early 2021.

CWD has not been detected in Washington. In 2021, the Washington Legislature allocated the Washington Department of Fish and Wildlife $465,000 for CWD surveillance and monitoring. This fall WDFW ran CWD check stations during the modern deer hunting season for the first time in a decade.

“We have been proactively preparing for possible detections of the disease for several years and in the past year drafted a Chronic Wasting Disease Management Plan to guide both monitoring for the disease and how to respond if and when it is found in our state,” said WDFW veterinarian Kristin Mansfield said in an email. “We have been actively sampling road killed and hunter harvested white-tailed deer for the disease in northeast Washington this hunting season. All returned samples to date have been negative for CWD. With the disease having been detected in Idaho, we will remain vigilant and continue our testing program this year, with plans to expand our sampling efforts in the future, dependent on funding. In the immediate future, we will discuss how these detections in Idaho impact the timelines of items in our CWD Management Plan.”

Marie Neumiller, the executive director of the Inland Northwest Wildlife Council praised WDFW for “being proactive in their approach to CWD.”

“I urge hunters to submit samples from their successful harvests,” she said in a text. “The more knowledge we have the better equipped we will be to fight this disease in our state. Ungulates especially in northeastern Washington face a variety of challenges. We need to make a concerted effort to minimize the impact that CWD will have on these herds in order to ensure that they can continue to thrive.”

In Idaho, Ross said hunters have been stopping regularly at check stations to submit samples. Per Idaho’s surveillance protocol, biologists have a 95% chance of detecting CWD if 1% of the wild population is infected.

“It seems like awareness is increasing,” Ross said.

Visit idfg.idaho.gov/cwd for more information.