4 minute read
CWD And The Science Behind Baiting And Feeding Bans
Zach Wood
Zach Wood is a public information officer in the DNR’s Office of Communications.
Since chronic wasting disease (CWD) was first detected in Wisconsin in 2002, the state has employed a wide array of strategies to slow its spread. As our understanding of CWD has grown, one of the earliest approaches — localized bans on the baiting and feeding of deer — has continuously shown to be a crucial available tool.
To understand why these bans are so important, we must first understand what CWD is and how it spreads.
CWD is a contagious, fatal neurological disease that affects the nervous system of deer, elk, moose and caribou. It belongs to the family of diseases known as transmissible spongiform encephalopathies, or prion diseases.
Prions are misshapen proteins that can spread CWD through direct animal-to-animal contact or through the environment via bodily substances or the carcass parts of an infected deer. Prions are extremely resilient and capable of remaining in the soil for years, potentially infecting several deer from a single source.
In short, when deer get together in the same place, the odds of infection increase.
Baiting and feeding encourages the unnatural congregation of deer, which allows for increased contact that otherwise would not occur in natural feeding environments. Bait piles are not the only way CWD spreads from deer to deer, but they increase the risk of transmission.
That’s why Wisconsin state law requires the DNR to implement a temporary baiting and feeding ban in any county where a CWD-positive deer is identified. Bans last three years within a county with a confirmed case of CWD and two years in an adjacent county if the confirmed case was within 10 miles of the county border. Ban periods must restart any time a new positive case of CWD is detected.
Farms And Food Plots
With regard to transmitting CWD, food plots and farm fields are different than bait piles. Although they also can be communal spots for deer, food plots and farm fields invite safer above-ground foraging and have a finite amount of food that’s not as concentrated as bait piles. Once it’s gone, it doesn’t come back until the following season, if at all, and deer tend to move on.
Bait piles, on the other hand, can be replenished when they run low. This means deer will continue congregating around the same spot throughout the season. CWD prions can linger in the environment long after an infected deer leaves the area, spreading the disease to far more deer.
Baiting creates a continuing risk for healthy deer, even if they aren’t infected on their first visit to a bait pile. Each return trip carries a greater chance of infection from any diseased deer that might have visited the spot since the healthy deer’s last visit.
Deer do come into close contact with one another and spread the disease in the wild, of course. However, baiting and feeding bans aim to address the unnatural congregations — those that can be controlled. These measures are just one piece of a larger puzzle in battling CWD, but they are an important one.
Learn More
For details on deer baiting and feeding regulations in Wisconsin, check the DNR's Baiting and Feeding Regulations webpage. For more on chronic wasting disease and ways to help stop its spread, visit the DNR's CWD webpage.
