"Some scientists say that the predators are essential to curbing the spread of Chronic Wasting Disease because they pick off weak deer."
"Are the wolves of Yellowstone National Park the first line of defense against a terrible disease that preys on herds of wildlife?
That’s the question for a research project underway in the park, and preliminary results suggest that the answer is yes. Researchers are studying what is known as the predator cleansing effect, which occurs when a predator sustains the health of a prey population by killing the sickest animals. If the idea holds, it could mean that wolves have a role to play in limiting the spread of chronic wasting disease, which is infecting deer and similar animals across the country and around the world. Experts fear that it could one day jump to humans.
“There is no management tool that is effective” for controlling the disease, said Ellen Brandell, a doctoral student in wildlife ecology at Penn State University who is leading the project in collaboration with the U.S. Geological Survey and the National Park Service. “There is no vaccine. Can predators potentially be the solution?”"
Jim Robbins reports for the New York Times November 12, 2020.
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