In a week, white-tailed deer will enter the peak of breeding season, which will bring a boom of activity to the fall woods.
Not only will bucks chase does and battle for dominance, but archery hunters will hit the woods in force, hoping to take advantage of the increase in deer movement. Hunters will employ a variety of tactics to increase their odds of tagging a buck, using calls and scents to entice deer within range.
While the use of deer scent is a proven benefit for archery hunters, it could increase the spread of a deadly disease affecting cervids such as deer and elk in parts of Pennsylvania and throughout North America.
Chronic wasting disease is an always-fatal affliction that degenerates the brain of an infected deer. It surfaced in the United States in the 1970s in Colorado and has since been found in 24 states and two Canadian provinces.
In Pennsylvania, CWD was first detected on a captive deer farm in Adams County in 2012. Since then, the disease has turned up in both captive and wild deer in several counties in the southwest and south-central portions of the state.
According to the Pennsylvania Game Commission, CWD was detected on a captive deer farm in Adams County during 2012, in multiple free-ranging deer in Bedford, Blair, Cambria and Fulton counties from 2012 to 2017, on captive deer farms in Bedford, Franklin and Fulton during 2017, in two captive deer farms in Jefferson during 2014, and in a free-ranging deer in Clearfield this year.
While there is no evidence that CWD is transmissible to humans or livestock, there are ongoing studies that raise concerns over a possible risk to people. Even though no CWD infections have been reported in humans, the U.S. Centers for Disease Control recommends that hunters do not eat meat from animals that test positive for CWD.
The presence of the disease in deer has wildlife officials on high alert, and as the Pennsylvania Game Commission and state Department of Agriculture look at ways to stop the spread of the disease, a debate has ensued over what works and what doesn’t.
At the center of the discussion, as archery hunters eagerly await the start of the deer breeding season — known as the rut — is the use of urine-based deer lure.
Chronic wasting disease is the result of a misfolded protein called a prion. When a prion enters the body of a deer, it causes existing proteins to become diseased.
Prions are shed through the saliva, urine and feces of infected cervids and can persist on the landscape for decades, according to some researchers. A healthy deer can become infected by contacting prions, either through direct contact with a CWD-positive deer or with contaminated soil and plants.
Many states, including Pennsylvania, have banned the movement of high-risk deer carcass parts — such as the head and spinal cord — from areas within the state where CWD is present, as well as to other states where the disease has been found. Hunters bring back the head of a buck they intend to get mounted, and the spinal cord sometimes isn’t removed when the loins of a deer are cut to make venison chops.
In Pennsylvania, the use of deer urine for hunting is prohibited in places where CWD is present, but the products are allowed everywhere else in the state.
New York prohibits the importation of whole deer, elk and moose carcasses from CWD-infected states, and the state is interested in doing more.
According to the draft of the CWD Risk Minimization Plan, the New York Department of Environmental Conservation is considering a complete ban on the use, sale and possession of products that contain cervid urine in an effort to keep prions off the landscape.
The public comment period for the plan has concluded, and it’s under review by New York DEC officials. If the plan moves forward, it would take effect in 2019.
New York is the only state to have eliminated the presence of CWD once it was found in the wild. The fatal brain disease was discovered in wild and captive deer in Oneida County in 2005, and there has been no recurrence of the disease.
When hunters use urine-based deer lure to attract deer, particularly during the rut, the lure often is deposited on the ground, and there is no test to determine if the urine contains prions.
Wayne Laroche, the Pennsylvania Game Commission’s special assistant for CWD Response, said there is no regulatory oversight of urine-based products by state or federal agencies and thus no way to confirm if the urine sold as deer lure and applied to the landscape is free of CWD prions.
“Consequently, we cannot determine it is safe prior to it going on the shelves, and we cannot follow up on determining where potentially infected urine was used after the fact,” Laroche said. “There definitely is a risk involved in using natural urine.”
Mitigating that risk isn’t easy, however, as the deer lure industry stands to lose significant money if its products are banned in states such as Pennsylvania, where deer hunting is popular.
Most lure manufacturers believe the risk is exaggerated and their products are safe.
Chip Hunnicutt, spokesman for the scent-maker Tink’s, which is based in Georgia and has been selling deer lure since the 1970s, said his company and other lure manufacturers have partnered with the Archery Trade Association to develop a monitoring program for urine-producing facilities.
According to Hunnicutt, 11 manufacturing facilities follow the monitoring program and provide 95 percent of the urine used on the commercial market. Facilities under the trade association guidelines adhere to enhanced testing of their animals, are closed to importation of cervids, and are double-fenced to limit interaction between captive and wild deer.
Also, Archery Trade Association facilities must be certified by CWD state or federal programs, which ensures they have at least a five-year history of no positive findings in their herds.
“It does get frustrating,” Hunnicutt said of the belief that the use of deer urine carries a risk of spreading CWD. “We’re not looking to endanger the herd, and we don’t believe our product does that.”
However, Dr. Krysten Schuler, a wildlife disease ecologist at the Cornell University College of Veterinary Medicine in New York, said she isn’t convinced that urine-based deer lure doesn’t pose a risk of spreading the disease.
Schuler, who has researched chronic wasting disease since 2002, said there is no oversight of urine products, and facilities aren’t required to participate in a certification program to test all natural mortality for the presence of CWD. She added that multiple studies have shown CWD prions are shed in urine, and relatively early — within the first six months of infection. A diseased animal can live for a year or more before showing any clinical signs of CWD.
“If you had a sick deer but it looked fine, and you collected the urine for a year and then it dies, and then you find out it had CWD, those products already went out there for a year, and there’s no way to trace it back,” Schuler said.
Adding to her concern is the fact that urine used for lure is collected from captive deer over a grate. In addition to urine, feces and saliva also go through the grate, possibly elevating the level of prions in the bottled product.
“Urine products aren’t pure,” Schuler said.
According to Hunnicutt, the saliva, feces and urine have the lowest concentrations of CWD prions, compared to the brain and spinal cord. He said it would take 33,000 gallons of urine to equal the infectivity of a portion of brain from a deer weighing one gram.
“The urine collected is free and clear of CWD prions. Period,” Hunnicutt said.
There are more than 1,000 deer farms in Pennsylvania — second in number only to Texas — that cater to several markets, including raising quality breeding stock, collecting urine for the scent industry, selling bucks for hunting purposes, and selling antlers.
Pennsylvania also is home to the largest natural urine production facility in the country, which is owned by Amish farmers and played a role in developing the Archery Trade Association monitoring program.
According to Glenn Dice Jr., president of the Pennsylvania Deer Farmers Association, the captive-deer industry has an impact of $7.9 billion to the nation’s economy. While Dice didn’t know the economic contribution of the deer lure industry, he said a ban on urine-based products would be devastating to the facilities that comprise that market.
Rather than look at a ban on deer urine, Dice suggested state wildlife agencies focus on cervid parts that contain the highest CWD risk.
“Expert CWD researchers consider urine the lowest risk of transmitting CWD. These experts indicated that muscle tissue from a de-boned deer carcass is extremely more infectious, potentially 100,000 times more infectious, than urine,” Dice said. “It’s curious PGC’s interest in discussing a potential urine ban, however, a significantly more infectious deer by-product, de-boned meat, is not being discussed.”
Laroche, of the Pennsylvania Game Commission, acknowledged that urine might pose a lower risk of spreading CWD compared to the movement of deer parts and even live animals throughout the state. But that doesn’t mean he isn’t concerned about urine-based deer lure and the threat it poses to the resource and hunting in Pennsylvania.
“Every time CWD turns up someplace new, it promises to cost the Game Commission thousands, if not millions, of dollars more to monitor and implement control measures there. It is easier to accept the risk if it is not your money being spent and not your deer dying,” he said.
Even if the concentration of prions is lower in deer urine, Schuler stressed there is no “safe dose” when it comes to transmitting CWD. It could take just one prion to infect a deer, she said, and most CWD studies use higher concentrations because the goal, for research purposes, is to create an infection.
Because prions don’t break down and can last for nearly two decades or more in the soil, using urine-based lure could pose a greater threat. Schuler pointed out that research has shown prions have an ionic charge and they can bind to soil particles, particularly clay.
“A hunter pours urine on the ground and it makes it more infectious, creating multiple hotspots of infection,” she said. “The prions don’t break down, and that increases the risk.”
An alternative to urine-based lure is being sold on the market in the form of synthetic deer attractants.
Rick Conley, president of the United Bowhunters of Pennsylvania, said while his organization hasn’t adopted a formal position on the use of deer lure, his group’s members generally believe synthetics work as well as urine-based products.
Conley also said he doesn’t believe a ban on deer urine would have a significant impact on archery hunting.
So are synthetic lures the answer?
“I think the compromise is to do anything and everything to control the spread of CWD. I’m not sure we know enough yet to accomplish that, but we need to err on the side of caution. I guess synthetics would be a reasonable compromise,” Conley said.
Hunnicutt, spokesman for the scent-maker Tink’s, suggested a different compromise — one he said will protect deer lure manufacturers and safeguard against the spread of CWD.
And it doesn’t involve a ban on deer urine.
“Just saying to ban urine is like throwing darts at a board right now, and that board is moving,” Hunnicutt said. “If they ban urine, what are they going to do when CWD doesn’t go away?
“Our recommendation to wildlife agencies is if you feel that strongly to ban something, how about banning urine that doesn’t come from facilities following the ATA certification program?”
Schuler added that anything posing a CWD risk needs to be scrutinized for the benefit of all parties involved, including hunters, wildlife managers and captive farms. All the groups have something to gain by stopping CWD, even if it means a ban on deer urine.
“We know there’s a risk there. It’s not zero,” Schuler said. “The risk is too great for what we’re putting out there.”
Reach Tom Venesky at 570-991-6395 or on Twitter @TomVenesky