Researchers at the University of Illinois studying the long-term effectiveness of deer culling programs in areas affected by chronic wasting disease found that the strategy has generally worked: The prevalence of CWD in tested Illinois deer remained at about 1 percent from 2002 to 2012.
A paper on the study, which appears in the journal Preventive Veterinary Medicine, was authored by Jan Novakofski, a professor of animal sciences at the U of I. The study itself was conducted in cooperation with the Illinois Natural History Survey.
"We know a lot about how far deer typically move," Novakofski said. "If they're sick, they're going to spread the disease that far. So if you find a deer that's sick, you draw that small circle and you shoot there."
He called this approach "a textbook scientific strategy for control."
"You reduce contact and you reduce the spread of infection with the smallest overall impact on healthy deer," Novalofski said.
The research team also found that hunters were killing more deer each year in each region of the state (north, central and south) regardless of CWD and CWD management. Statewide, the number of deer killed by hunters went from 147,830 in 2001, before the appearance of CWD, to 181,451 in 2012. The only exception: Two counties out of 10 with cases of CWD saw a reduction in hunter harvest over the same period.
"We wanted to know whether Illinois hunters have fewer deer to hunt now than they did before CWD," Nohra Mateus-Pinilla, a wildlife veterinary epidemiologist for INHS, who led the study with postdoctoral researcher Mary Beth Manjerovic. "We found that hunter harvest has increased, and the prevalence of CWD has been maintained at low levels for 10 years in Illinois."
Read more about the U of I study in the Nov. 1 issue of Illinois Outdoor News.