The presence of CWD in the Jackson elk herd will impact hunting opportunities and reproduction
Chronic wasting disease (CWD) is a deadly neurological disease found in elk, deer and moose. In late 2020, the first elk in the region with CWD was detected. It was shot by a hunter in Grand Teton National Park—not far from where the Jackson elk herd is fed in the winter on the National Elk Refuge.
The announcement worried biologists who were concerned that feedgrounds act as a superspreader of the deadly disease because of the density of animals.
Doug Brimeyer, the deputy chief of wildlife for Wyoming Game and Fish, said the presence of the feedground was one reason behind a recent study published in Ecosphere last month.
Once there is a seven percent prevalence of CWD, the study predicts a modest decline of elk. It also predicts a mean of 12 percent CWD prevalence in the herd but it could go as high as 20 percent. Brimeyer said a high prevalence of the disease could impact hunting tags.
"CWD and hunting are both additive to the mortality of the population. And so for the last 20 years, our goal has been to manage the Jackson elk herd to 11,000 animals and, to do that you have hunting seasons on cows and the antlerless segment of the population," he said.
Brimeyer said this study provides insight into important management tools for the future of this unique herd. Since the herd is in western Wyoming where the numbers of predators on the landscape are higher, the herd is not as successful in reproducing, so the prevalence that the population could sustain will be lower than other herds in the state.
"So if CWD influences population performance, it's going to be important for managers to know that," said Brimeyer. "We want to maintain that long-distance migration and reduce the amount of human-caused mortality on those reproducing animals."
Brimeyer added that there are a lot of unknowns regarding feedgrounds and CWD.