Imagine the largest deer you could ever shoot was one that only made it to two-and-a-half years of age. At best, that’s a buck with a small four-by-four rack, or a doe that likely was only able to produce one or two years of fawns to help sustain the local herd. For some places in North America, where its prevalence has escalated to more than fifty percent of sampled deer populations, chronic wasting disease (CWD) is starting to suggest those unlikely situations may become a reality. With its detection rate in North Dakota limited to anywhere between one and five percent of the harvested samples in the units where it has been found, CWD is present and a new task force initiated by the North Dakota Game & Fish Department (NDG&F) aims to keep it from hitting the herd harder.
“This task force is really set up in order to reassess where we’re at with the issue, assess how we can fold in the best management practices to address it, and ultimately come up with an updated CWD plan,” explains Charlie Bahnson, NDG&F Wildlife Veterinarian.
The first detection of the prion-based disease in wild deer in the U.S. came in 1981 with a specimen in Colorado. By the 1990s, wild deer in that state’s herds and some in neighboring Wyoming were sampled with the disease. In 2009, the first deer in North Dakota was found in firearms unit 3F2 with CWD, and as of 2020, deer in five units in the state have tested positive for it. Along with the spread of the disease since that time has come more than 20 years of science and management techniques helping to limit its advancement among deer populations, though it is now found in deer in more than
half of all U.S. states. With that knowledge, and the growing concern of what CWD can do, the NDG&F’s task force was created to improve efforts and explore new ways of limiting the disease’s spread and impact.
According to Bahnson, “[the task force] will assess how we’re directly managing the disease on the ground. But what has really emerged in the last decade is that the key to managing CWD is hunter behavior. So as the department, [we ask] how can we get buy-in with people and various stakeholders and really shift hunter behavior to the best practices to lower the risk of CWD spread. So communication strategies and outreach strategies will probably be a pretty strong component of what we do going forward.”
Localized mule deer buck populations in areas of Saskatchewan paint the direst picture for what CWD can do. There, prevalence of the disease among those deer has recently risen to 70 percent. Those levels are now beginning to impact the age structure of deer, with the high level of infection limiting the quality of bucks and does on the landscape, with many deer being infected with CWD shortly after birth, and limiting their lifespan to as little as 18 to 20 months in areas where the disease is prevalent. At the family group or herd level, the ability of those animals to handle environmental pressures decreases
further, and the number of quality bucks decreases along with does capable of sustaining huntable populations in those areas. Currently, sampling rates in North Dakota of both whitetailed and mule deer in those areas where CWD is present have resulted in a prevalence rate of the disease between one and five percent, year-to-year. Limiting its expansion, and more importantly, it’s transfer to other areas of the state where it currently is not found, is a primary focus of the task force in its goal of preserving good field experiences and healthy, huntable populations.
“I speak as a representative of the department but I also speak as a life-long deer hunter as well, and I can say that the hunting tradition and the culture of hunting in our communities and our state is incredibly rich and is something that we really want to preserve,” Bahnson stresses, “central to that is a healthy, resilient deer herd, and so a population that is completely free of CWD or a population with a low level – one to five percent that maybe have this disease – that’s a population that is still pretty resilient, and something we can enjoy in the long term,” he concludes.
By: Nick Simonson