On a gray, dreary Monday in mid-October, Charlie Bahnson spent a day on the UND campus visiting with wildlife students about chronic wasting disease and a student-led effort to collect deer heads this fall in the Grand Forks area for the North Dakota Game and Fish Department. Grand Forks is on the department’s rotating schedule of sites to sample hunter-shot deer for CWD, the degenerative brain disease that’s fatal to deer, elk and moose, and the UND Chapter of The Wildlife Society is overseeing the local effort.
Bahnson’s position as wildlife veterinarian for the North Dakota Game and Fish Department puts him front-and-center in the state’s battle against CWD.
And when it comes to CWD, the answer to most questions is “no,” Bahnson said.
“Is there a treatment for CWD? No,” Bahnson said. “Do we have some sort of vaccine that we can use to prevent infections in an area? No. Does the deer ever recover? No.
“So, you’re kind of seeing a theme here. We don’t have a way to get it off the landscape, and we don’t really have a way to get it out of the herd or eradicate it feasibly.”
That’s something for hunters to think about as the firearms deer seasons approach; the deer gun season begins at noon Friday, Nov. 8, in North Dakota and a half-hour before sunrise Saturday, Nov. 9, in Minnesota.
The cause of CWD isn’t a virus or bacteria, but instead is a misfolded cellular protein known as a prion, which spreads from sick to healthy animals through nose-to-nose contact and bodily fluids such as urine, saliva and feces. Prions persist on the landscape indefinitely and can survive temperatures in excess of 1,500 degrees, Bahnson said.
Carcasses from sick or dead animals that were infected also can spread CWD.
“Once that happens, the clock starts ticking, and it’s truly a death sentence,” Bahnson said. “Eighteen to 20 months later, we’re going to have this deer that everybody thinks about -- this emaciated, skinny deer that doesn’t survive a whole lot longer.”
First diagnosed in 1967 in a Colorado elk research facility and a few years later in a similar Wyoming facility, CWD falls into a category of diseases known as transmissible spongiform encephalopathies – including mad cow disease in cattle, scrapie in sheep and goats and Creutzfeldt-Jakob disease in humans – which basically turn the brain into a sponge.
CWD has been found in 26 states, three Canadian provinces, South Korea, Finland, Norway and Sweden, according to the Minnesota Department of Natural Resources. Eight confirmed deer or elk farms and 52 wild deer have tested positive in Minnesota, the DNR said, all in the southeast, north-central and central parts of the state.
To date, 17 deer – all wild – have tested positive for CWD in North Dakota, Bahnson said. First detected in 2009 in south-central North Dakota, CWD in the past year has been found in northwest North Dakota and, most recently, McKenzie County in the North Dakota Badlands, where a mule deer buck shot with a bow in September in hunting Unit 4B tested positive.
The deer in 4B was tested as part of a routine sampling effort. A second mule deer buck taken during the September youth season in Unit 3A1 in Divide County also tested positive.
Both deer appeared perfectly healthy, Bahnson said. That’s been the case with most of the nearly 30,000 deer Game and Fish has tested since it began sampling for the disease in 2002, he said.
“A big misconception is the idea that, ‘I shot this deer, it looks perfectly healthy, I’m not going to get it tested,’ ” Bahnson said. “The vast majority of deer that we’ve tested that have been positive have looked perfectly healthy.”
The exception was an emaciated 4½-year-old whitetail doe found dead in February in Williston city limits that tested positive for CWD. A subsequent sharpshooting effort that produced 52 additional deer for testing in the same area found no further positives, he said.
The goal during the coming gun season is to test about 3,000 deer from 95 sampling sites across the state, Bahnson said.
If there’s any good news about CWD in North Dakota, it’s that the prevalence in infected areas remains low, at about 1%, he said. That compares with 25% to 30% in the most heavily infected areas of Wisconsin, where deer densities of 40 to 50 per square mile also are substantially higher than the four to six deer per square mile in North Dakota.
Baiting, the practice of putting out feed to draw deer into shooting range, is illegal in CWD-positive areas of North Dakota in addition to state and federal public lands. The department strongly encourages hunters not to bait, even where legal, to reduce the potential for spreading the disease by congesting deer into small areas.
Baiting is illegal everywhere in Minnesota.
“The objectives are pretty simple,” Bahnson said. “It’s to keep CWD out of areas we don’t have it, and to keep the prevalence low where we do. … There’s a substantial mortality rate that happens the more you have CWD on the landscape.
“Where we have it, we have about 1% prevalence, and if we can keep it there, we might be fine. The concern is that once it starts to grow, both the effect becomes stronger, and your options become weaker.”
Hunters play role
Words such as “prion” and “transmissible spongiform encephalopathy” might cause people to roll their eyes, but the message for hunters is that CWD is a serious threat well-founded by science, Bahnson says. In addition to not baiting, hunters can help limit its spread by obeying regulations that prohibit the transport of high-risk body parts such as the brain and spinal column, where the prions are found, outside of infected areas and properly disposing of carcasses.
Game and Fish this year will take the added step of sending heads from any deer that test positive to North Dakota State University, which has a commercial-grade incinerator that gets hot enough to deactivate the prions, Bahnson said. The rest of the heads will be buried in a landfill, he said.
North Dakota and Minnesota both have strict regulations preventing the import of deer, elk and moose carcasses across state lines, regardless of CWD status, and from infected areas within the states. Only quartered animals with no part of the brain or spinal column attached, or processed meat can cross state lines or outside infected areas; heads and spinal columns must be left behind.
In the case of trophy animals, hunters can work with taxidermists to have the lymph nodes removed for testing or make sure the skull plate and antlers are clean with no meat or tissue attached.
Regulations vary by state so hunters need to plan accordingly. That might be an inconvenience, but it’s one of the few weapons against the disease at this point, Bahnson says.
The goal is to instill what he calls a “give a damn” culture among hunters.
“Our behavior can steer the ship moving forward,” Bahnson said. “We are masters of our fate, and so I try to focus on that messaging.”
Take advantage of testing
To date, there is no conclusive evidence that CWD can be transmitted to humans, but the Centers for Disease Control and Prevention recommends hunters don’t eat meat from animals known to be infected. In addition, hunters should have their animals tested for CWD if it comes from an area known to have the disease.
Testing is voluntary in North Dakota, but it’s mandatory in the CWD management areas of central, north-central and southeast Minnesota where the disease has been found.
After field-dressing their deer, hunters in the Minnesota areas where testing is mandatory must take the deer to a sampling station, where DNR staff will remove lymph nodes and tissue samples for laboratory testing.
“Protecting our white-tailed deer population is a shared responsibility, and we’re thankful for hunters who help combat CWD by submitting samples,” said Michelle Carstensen, wildlife health program supervisor for the DNR. “These samples provide data that help us better understand the prevalence of the disease in wild deer in these areas.”
The DNR since 2002 has tested more than 64,000 deer. The goal this year is to test about 17,000 deer, said John Williams, northwest regional wildlife supervisor for the DNR in Bemidji.
For hunters, information – not fear – is the best defense against CWD, said Craig Engwall, executive director of the Minnesota Deer Hunters Association in Grand Rapids, Minn.
“I really encourage our members and hunters just to dig into the issue and pay attention,” Engwall said. “While (CWD) may not be in their area, once it’s there, it’s almost impossible to eradicate unless it’s very small, and that could vastly change the way a hunter or hunters view the situation.
“It would affect things around them like who will process my meat, does my family want to eat the meat, do I want to eat the meat (and) what precautions do I want to take.”
Engwall, who lives and hunts in northern Itasca County of northern Minnesota, said he personally doesn’t have a big concern about CWD because it hasn’t been found in that area.
“Would that change if there were positives found near me? Yeah, it would,” he said.
In that context, the carcass restrictions, testing requirements and the focus on proper carcass disposal are small prices to pay for a healthy deer herd and the benefits hunting provides, the Game and Fish Department’s Bahnson says.
“I would just reiterate this is a serious threat, and it’s really up to us to decide if we’re willing to make the sacrifices to take this thing on,” Bahnson said. “We’re all wanting the same thing – we’re wanting to preserve our hunting heritage, we’re wanting to maintain healthy deer herds for the next generation, and hopefully we can recognize those commonalities and move forward.”