Chronic Wasting Disease could be in Minnesota for the long haul
One tweak will be noticeable in chronic wasting disease regulations for this year's deer hunt in the southeastern part of Minnesota, this one around Wabasha.
In looking ahead, however, ominous possibilities could change the hunt in the Preston area, another in the state and beyond. Neither is a certainty, though one is looking closer.
"As far as (compared with) last year, the biggest change was the positive deer around that Wabasha area," said Patrick Hagen, Department of Natural Resources statewide disease response coordinator. The deer permit area there is now called 642 (instead of 342) and with it comes carcass movement regulations, and mandatory CWD testing for deer at least one year old the opening weekend.
He recommended hunters going out in any permit area double check regulations to make sure they are in compliance.
As for CWD itself, numbers are rising slowly, almost all in this region. "CWD was detected in 43 hunter-harvested deer during the 2023 fall hunting seasons," according to the DNR. "Of these, 91% were from the southeast, a region that continues to see persistent CWD infections in wild deer."
Statewide, 279 deer have tested positive for CWD since 2010; another 13 were found in captive herds, Hagen said. Compared with other states, such as Wisconsin, that number is very low. Since 2002, more than 120,000 deer have been tested; the DNR's cost for it was $21.3 million, he said.
Hunters this year may now take a deer head with or without the cape and neck attached to a licensed taxidermist outside the CWD management area as long as it's delivered within 48 hours, he said.
CWD is an always-fatal disease affecting cervids such as deer, moose, elk and caribou that can be passed via saliva, feces, urine and antler velvet. The prions that cause it can also get into the soil, and then into leaves that deer eat.
It was first found in wild deer in 2010 in a very old doe shot by an archer near Pine Island. The DNR allowed people to shoot many deer in that area to both cull the herd to lower chances of more infections and determine if more cases were out there. After a few years, the DNR determined chance of another infected deer in the area was near zero. Then, in 2016, a CWD-positive deer was found in Preston and the disease expanded until it has now been found throughout much of the region, though in small numbers.
As usual this season, the DNR says deer at least a year old and shot in the first weekend of the A season in the CWD permit areas must be brought to a testing station. At other times, hunters can drop off the heads in collection areas, get a test kit to extract the lymph nodes themselves or find those, often taxidermists, trained to collect the nodes, Hagen said. Last year, hunters testing their own deer had a success rate in the high 80-percent range, he said.
In looking five years ahead, Hagen said he isn't quite sure what to expect.
"CWD is a rare event in Minnesota," he said. "Our prevalences are not very high ... in that sense, I feel good."
But then there is Preston and that is where there might be one of the ominous possibilities. "I think there are areas of the state that we probably will not get rid of CWD with the current status of it," he said. One is the Preston area. So in that sense, he feels worse.
In fact, Preston might be close to the point where the DNR might forget trying to stop or slow it and concentrate on keeping it contained, he said. "We are not there yet, but it is a possibility in the future," he said. "It would just be trying to focus our resources. We don't want to focus our resources on a losing battle."
Also looking ahead, he said, "there is a ton of research going on about CWD right now." One field is trying to find an accurate test hunters can use in the field instead of using lymph nodes. But that has to be validated through the US Department of Agriculture and that could take some time, he said.
One of the ways the DNR is trying to cull the herd is to offer hunters a chance to take two deer in the Whitewater area, three around Wabasha and five in much of the rest of the region. The result? No big change in overall deer numbers, said Todd Froberg, DNR big game program coordinator.
He hunts near Lanesboro and said his party hasn't seen any big drop in deer numbers, though the number of older bucks seems to be dropping. The DNR is getting the younger age structure it was hoping for, though hunters might not be happy about that.
About 96 percent of successful hunters take only one buck (three are allowed in most areas) and 80 to 85 percent shoot just one deer, he said. Only 4 to 5 percent shoot three deer and those harvesting four or more is less that 1 percent of successful hunters, he said.
The number of firearms hunters statewide has been dropping by 1.5 to 2 percent annually while that number is a bit higher in the core CWD area, maybe 2 to 3 percent, Froberg said. Whether CWD has had something to do with it, or the aging population is hard to say, he said.
Dr. Michael Osterholm, an internationally known epidemiologist, offered a more ominous possibility when testifying before a Minnesota House Committee last fall. He said while it's not believed CWD can be transmitted to humans, the same was thought about mad cow disease in England, but humans did get it, he said.
Whether CWD has been transmitted to humans is unknown because no one knows what it would look like in humans, he said. If found in humans, "there would be a public health and economic crisis," he said.
The second, and just as ominous, thing he stressed is that the CWD-causing prions are evolving. "This is the great unknown and this is the challenge we have," he stated. "The prion evolution that we are watching right now in front of our eyes means what data we had from 10 years ago or five years ago may not at all hold today as to vulnerability not only to humans but also to non-cervid production animals or wildlife ... we really are into a new setting."
If that does happen, a DNR report in 2016 said "the MNDNR would realize substantial reductions in license sales and Federal Aid reimbursements and negatively affect the agency's ability to manage all wildlife in the public trust."
