CWD remains serious point of concern in Midwest deer herd
Springfield — The annual report on chronic wasting disease in Illinois’ deer herd is still weeks away, but there doesn’t appear to be any reason to expect a drastic change in the numbers.
DNR’s report covers the fiscal year, so the FY2015 report will include confirmed cases from July 1, 2014, to June 30, 2015.
There were 59 cases of CWD confirmed during FY2014 – the most ever recorded since DNR began filing the reports in 2003. The state sampled 7,432 deer during FY2014, down from the 8,069 sampled in FY2013 and the 8,203 sampled in FY2012. The 59 cases came from 13 counties.
As hunters and wildlife watchers wait for the new report, little CWD activity has been reported in the state since last year’s report.
Meanwhile, nationally the disease has been a hot topic, most recently due to a recent report that CWD was confirmed in Michigan’s deer herd. The disease has been confirmed in Saskatchewan, Alberta, and 18 other states, including Missouri and Wisconsin.
According to Michigan’s DNR, 34,207 deer, 1,607 elk and 70 free-ranging moose were tested for CWD from 1998 through 2014. During roughly the same period, 21,000 deer and elk were tested from that state’s licensed captive cervid facilities.
Wisconsin’s approach to CWD, which some call “passive,” hasn’t found support among researchers and wildlife-agency personnel grappling with the always-fatal ailment, now documented in wild deer or elk in 20 states and two Canadian provinces.
For instance, at February’s annual Southeast Deer Study Group meeting in Little Rock, Arkansas, Dr. Jim Crum – chief deer biologist for the West Virginia Division of Natural Resources – said Wisconsin’s policy shift on CWD in 2013 “cut our legs off at the knees.” West Virginia has had 175 whitetails test positive for CWD in recent years, third in Eastern states behind Illinois and Wisconsin, which has nearly 2,840.
When Michigan announced its first case of CWD in wild deer – a sick doe near Lansing – its DNR enacted feeding and baiting bans in three counties, and unlimited antlerless deer hunting licenses for this fall’s hunting seasons.
In Wisconsin, despite sampling the second-lowest number of deer (5,414) in its 14-year monitoring program, DNR documented a record 6.1 percent disease rate with 329 positive tests in 2014.
Missouri reported 11 new cases of CWD in wild deer after concluding its 2014 tests, bringing its total to 24 since discovering CWD in 2010 at a private enclosure. One of 2014’s diseased deer was a buck from outside the state’s initial six-county CWD containment zone. Missouri has also found CWD in 11 captive deer.
In contrast to the Wisconsin DNR’s CWD policy, the Missouri Department of Conservation reminds citizens what’s at stake. Its recent summary notes:
“Infectious diseases such as CWD could reduce hunting and wildlife-watching opportunities for Missouri’s nearly 520,000 deer hunters and almost 2 million wildlife watchers. Deer hunting is an important economic driver in Missouri, and gives a $1 billion annual boost to state and local economies.
“Lower deer numbers from infectious diseases such as CWD could hurt 12,000 Missouri jobs and many businesses that rely on deer hunting as a significant revenue source, such as meat processors, taxidermists, hotels, restaurants, sporting-goods stores, and others. CWD also threatens the investments of thousands of private landowners who manage their land for deer and deer hunting, and who rely on deer and deer hunting to maintain property values.”
Research led by Kevin Gough at the United Kingdom’s School of Veterinary Medicine and Science detected prions circulating in dust on a farm contaminated with sheep scrapie. The researchers wrote: “The presence of infectious scrapie within airborne dusts may represent a possible infection route, and illustrates the difficulties that may be associated with the effective decontamination of scrapie-affected premises.”
Also, a study led by Sandra Pritzkow at the University of Texas Medical School in Houston found “wild-type hamsters were efficiently infected” by eating prion-contaminated plants, including CWD. Pritzkow wrote: “These findings demonstrate that plants can efficiently bind infectious prions and act as carriers of infectivity, suggesting a possible role of environmental prion contamination in the horizontal transmission of the disease.”
With reports and findings like these, it’s no wonder biologist Gary Alt, who assisted Professor James Kroll during Wisconsin’s “deer trustee” process three years ago, believes CWD will spread throughout the whitetail’s range within 200 years.
When speaking at the National Deer Alliance “summit meetings” in Louisville in early May, Alt wondered rhetorically if deer would still be on the landscape in two centuries.
“What happens between now and then?” Alt said. “The jury’s still out. But we shouldn’t assume anything about CWD’s long-term impacts on the species.”