If you hunt big game in the United States, you have probably heard about Chronic Wasting Disease (CWD) unless you have been living under a rock for the past decade. CWD and how it will impact the management of ungulates is a hotly debated topic, one with many facts and even more unknowns. One thing is certain, CWD will change how deer (and elk) are managed, hunted, and conserved and could be a real game changer for private landowners as well as state fish and wildlife managers. MDF takes CWD very seriously and believes it is our duty to address key issues surrounding the management and hunting changes that may take place as we deal with this disease.
CWD is one of a family of diseases called transmissible spongiform encephalopathies (TSE) similar to mad cow disease in cattle, scrapie in sheep, and Creutzfeldt-Jakob disease in humans. It is an always-fatal nervous system disease found in cervids (deer, elk, moose, reindeer) caused by a misfolded protein, called a prion.
There is no known cure for CWD, it is not treatable, and is ultimately fatal to infected deer.
Infected deer often do not show any symptoms until the final stages of the disease which can take up to two years to manifest. CWD can be transmitted through direct animal-to-animal contact, contact with saliva, feces, carcass parts of an infected animal, and can even spread through soil that has been contaminated with any of the above tissues or fluids. Movement of infected animal parts or soils can spread the disease.
Affected deer will show signs of difficulty in movement and significant weight loss over time. Decreased interaction with other deer along with listlessness, lowering of head, tremors, repetitive walking in set patterns, and nervousness are often signs of an infected animal that is about to succumb to the disease. Excessive salivation and grinding of teeth may be observed. Increased thirst can lead to increased drinking/urination, which may help spread disease. Loss of the fear of humans and appearance of confusion are also common.
Scientists have documented that CWD can have negative population effects in elk, mule deer, and white-tailed deer. Published models predict CWD has a population level impact when its prevalence within the herd exceeds 27%, and in areas where little active management of the disease has been done, herds are currently infected with CWD at rates higher than 40%. Currently CWD is found in wild or captive cervids in 30 states, four Canadian provinces, Norway, and South Korea. Twelve states and three Canadian Provinces with mule deer populations are included in the affected area. So, it is found in more than 50% of the states where MDF works and hunters target mule deer as a game species.
CWD may cause significant changes in the way managers deal with a CWD-infected herd and statewide deer management in general. States can require a quarantine of deer parts (head, spine, bones) being moved from a CWD area and try to limit the prevalence of the disease below 5%. States have also ceased moving deer (translocations) as a result and in some cases have instituted special hunts/harvest to reduce deer in outbreak areas. Management of deer densities (fewer deer per square mile) and the number of older male deer (big bucks) in a herd may help limit the disease but this approach would be highly controversial.
Hunters have also been impacted by CWD. Reduced herd densities can lead to fewer hunting opportunities over time along with the objective of fewer older male deer can reduce opportunities for larger buck harvest. The restriction of moving animals or animal parts can lead to frustration, increased preparation for boning/caring for meat, and illegal movement of potentially affected deer/parts which could spread the disease outside the zone.
Misinformation has caused confusion and in some instances, disregard, for the seriousness of the CWD issue.
Bans on urine based scent, changes to hunting seasons/harvest rates, and safety issues are all realities with CWD and hunters. Taxidermy and meat processing plants are also being affected with some requiring a negative test before processing or even refusing to take animals from positive areas.
So, what can you do?
If you hunt in a CWD area, do not shoot, handle, or consume any animal that is acting abnormal or appears to be sick.
Contact authorities with the location if you do see potentially CWD-infected deer. Also make a decision before you harvest an animal on whether you would consume the meat from a positive deer (don’t eat brain, spinal cord, eyes, spleen, tonsils, or lymph nodes). Although CWD has not been documented to be transmitted to humans, would you take the risk? Some states will provide you with a replacement tag if an animal tests positive but that is not guaranteed. If your animal tests positive, it is recommended meat not be consumed.
So, what can you do to help with the issues surrounding CWD? MDF recommends the following five simple steps to help limit the spread of CWD after you harvest an animal.
Know Before You Go/Be Prepared
Understand whether the area you are hunting has CWD and any special regulations associated with hunting regulations or disposal of carcasses. Ensure you have the proper safety equipment (latex/rubber gloves) to protect yourself.
Respect State Regulations
Follow the rules set out by the state, don’t move deer carcasses or parts out of CWD positive areas if prohibited, dispose of deer carcasses/bones in approved landfills. If you hunt in a quarantined area, respect the quarantine!
Test your Harvested Animal
Get a Chronic Wasting Disease test completed on your harvested animal, for disease monitoring and your safety. This also helps managers monitor CWD prevalence and detect new infected areas early, which can give managers a better chance to slow the spread of the disease. Many states have specific drop-off places, dumpsters, or CWD testing stations. MDF has helped fund CWD dumpsters in numerous states.
Leave the Bones Behind
Be prepared to bone out the meat from an animal if possible, clean all bone/ tissue from anything taken from the field (including a skull cap). This is the surest way to not spread infected parts to new areas by accident or during carcass disposal. Boning meat is simple and does not take much more time to complete. Instructional videos are readily available. I have been boning out my animals (except for those that I want to make bone broth from) for years and a benefit is a lighter load to haul out.
Clean your hands and tools in addition to the deer head/skull/tools – be prepared to remove all tissue from skull caps/skulls by boiling/soaking in bleach after getting back to camp or home, preferably before leaving the CWD zone. Make sure you clean your knives/tools and other processing equipment, a five-minute soak in a 40% bleach solution can inactivate prions.
As hunters and conservationists, we have an obligation in helping to limit the spread of this disease and limit the risk and probability of infecting new areas. CWD is here to stay; we must understand how to deal with it and how it will affect hunting and deer conservation. MDF is a supporter of the CWD Alliance and will continue to work on this issue for the future of mule and black-tailed deer conservation.
For more information
- This article first appeared in the Summer 2022 issue of MDF Magazine, exclusive to MDF Members. Join MDF today to start receiving your copy quarterly, and support our work.
Steve provides the Mule Deer Foundation leadership on all things related to mule and black-tailed deer conservation. Steve is a Certified Wildlife Biologist® and has over 30 years in wildlife conservation profession. Steve earned his Master’s degree from the University of Wyoming and B. S. degree from the Pennsylvania State University. Steve is a Fellow of The Wildlife Society and the National Conservation Leadership Institute, and resides in Red Lodge, Montana with wife, two kids and two labs. His experience in federal agencies, the private sector, and non-profit conservation worlds, provide a unique skill set valuable for work that MDF does for deer and other wildlife. He believes habitat is the key to properly managing sustainable wildlife populations across the many landscapes they are found. When he isn’t tirelessly managing the Conservation needs of MDF, he enjoys bowhunting, fly-fishing, and a recent infatuation with deep sea fishing.