CWD Worsening Fast in Parts of Wisconsin
Patrick Durkin 04.30.13
Those who think Wisconsin should just “learn to live” with chronic wasting disease (CWD) can now see this surrender to CWD taking shape as “nature takes its course” on the state’s deer herd.
In fact, folks near Spring Green are living the realities of such clichés. One farmer in the Wyoming valley of north-central Iowa County has shot 21 CWD-positive deer from his family’s 700 acres since 2008, with 11 falling since April 2012.
Those are just a few of the sick deer in a 144-square mile area where CWD is rising at “unprecedented” rates. That one-word assessment came from Bryan Richards, CWD project leader at the U.S. Geological Survey’s National Wildlife Health Center in Madison, after reviewing the latest CWD reports from Robert Rolley, a Department of Natural Resources researcher in the wildlife science bureau.
Rolley, Richards and about 50 other citizens, biologists and agency staff were at the University of Wisconsin-Stevens Point on April 6 to help implement 62 recommendations from the “Deer Trustee Report,” Dr. James Kroll’s guide to revamping Wisconsin deer management.
Rolley, too, used one word ,“frightening,” to assess CWD’s increase in the 12- by-12-mile area around the Wyoming valley, just south of Spring Green. The eastern border of this diseased block abuts CWD’s core area (northeastern Iowa and northwestern Dane counties), where the disease was first discovered 11 years ago.
What constitutes “unprecedented” and “frightening?” First, realize the infection rate in the core area is increasing about 10 percent annually. Richards said that resembles annual infection rates of mule deer in southeastern Wyoming’s Converse area, where 40 to 50 percent of the herd is infected.
Now consider Wisconsin’s north-central Iowa County:
- CWD’s annual growth rate for all deer (both sexes combined) 2.5 years and older is 27 percent.
- Annual disease rates for adult bucks (18 months and older) are doubling every two to three years.
- Roughly every third buck 2.5 years and older is infected, as is one in every six yearling bucks (18 months old). Infected deer live two years or less.
- Although the number of diseased females is lower, the infection rate for does 2.5 years and older is growing 38 percent annually, faster than for males.
“I’m not aware of data anywhere showing wild, free-range deer with similar infection rates,” Richards said. “The only thing worse was the Stan Hall farm (Buckhorn Flats, near Almond), whose penned herd of 76 deer went from one sick deer to 60 in five years in the early 2000s.”
That might sound like mere statistics to some people, but not to Matt Limmex, 49, an Iowa County dairy farmer who has spent his life on the family’s property. Of the 11 sick deer killed on Limmex’s lands the past year, six fell during 2012 gun seasons.
The other five? Limmex shot them at the DNR’s request after noticing the “droolers and shakers” near his farmyard. In three cases, the deer were so sick they couldn’t flee when Limmex approached. The DNR retrieved the carcasses for testing and disposal.
“I hate to see this,” Limmex said. “It’s disheartening. I just want to get sick deer off the landscape.”
Limmex said his family deploys about 14 hunters each year during November’s gun season. They’ve also used agricultural shooting permits since 1991 to control the herd. Even so, this is the first time he senses deer numbers decreasing.
“It seems like the disease might be affecting the herd now,” he said.
So, what’s causing CWD rates in Wisconsin’s Wyoming Valley to exceed those in the original disease zone next door? And will CWD shrink local herds, as experts have long predicted? No one knows, and Wisconsin lawmakers and the federal government aren’t inclined to find out.
The only current state-funded deer research by the University of Wisconsin is studying whether predators are affecting whitetails in the state’s Northwoods. Meanwhile, Professor Michael Samuel at UW-Madison is using federal funds to study if deer leave CWD-causing prions in feces, breeding scrapes, and mineral licks. But that research is ending soon.
“We’re puzzled by what’s going on in the Wyoming Valley,” Samuel said. “It’s very disturbing, but CWD research is on the way out. We could generate hypotheses and proposals to study what’s behind the increases, but I doubt we’d get the funding. There’s little interest in CWD these days, Wisconsin and nationwide.”
