Targeted removal of deer

The Minnesota DNR uses targeted removal, often referred to as culling, as one of its tools to manage chronic wasting disease in the DNR's aggressive efforts to keep Minnesota's deer population healthy.

Targeted culling involves contracted sharpshooters removing deer in areas where CWD has been detected and is conducted in partnership with the U.S. Department of Agriculture's Wildlife Services, typically during the winter months outside of regular hunting seasons.

Why does the DNR cull deer?

The DNR conducts culling to:

• Remove additional positive deer and any potentially infected social groups.
• Reduce the potential for the disease to spread to more areas.
• Lower deer densities in a small area to reduce disease transmission.
• Launch a “surgical strike” on known areas of the disease.

Culling is one of the most effective ways to remove infected deer. Since 2010, more than 270 positive wild deer have been detected statewide. Of those, around 30% of all positive deer in Minnesota have been removed by culling efforts.

How does targeted culling work?

The DNR only culls deer within two miles of a CWD-positive female deer or group of males where CWD has been detected in the last two years. Culling is not done across entire deer permit areas.

Safety is the number one priority; the USDA's wildlife services personnel will only shoot deer where it does not pose a safety risk to people, livestock and property. Culling only takes place on state-owned properties or private land where written permission is granted by the landowner.

Removal work is done at night with suppressed rifles using thermal imaging, night vision and non-toxic ammunition. Bait is placed in plastic tubs on the ground to attract deer in a safe and efficient manner for shooting. If a positive deer is removed from a bait site, the bait tub and bait is removed, properly disposed of in a lined landfill and replaced with brand new materials to prevent any potential further spread of CWD.

USDA shooters may remove deer by one of three methods:

• Mobile: Driving from site-to-site and removing deer by shooting from inside of the vehicle onto properties that gave permission to conduct activities
• Stationary: Sitting at a bait site removing deer that visit that site
• Trapping: Best for sensitive sites or small properties, using a live trap (clover trap) to hold deer until dispatch.

Where does culling occur?

Culling work is done in select CWD zones. Locations will be listed on this page once DNR staff determines areas where culling will occur.

Culling has occurred regularly in southeastern Minnesota, where the disease was first detected and is persisting. Additional culling operations may be added if there are individual females or groups of males detected with disease.

Focus areas are created within two miles of a CWD-positive female or group of males that have been detected in the last two years.

Females are less likely to disperse from their birthplace and a positive result from an adult doe typically indicates close proximity to a local source of infection.

The detection of groups of infected males can be a sign of close proximity to a local source of infection.

Single, CWD-positive bucks are not always a sign of local infection due to bucks’ extensive traveling behavior during the rut.

What does the DNR do with deer that are culled?

Participating landowners that sign up with USDA wildlife services to allow culling on their property have the option to receive venison from the project after test results are received. Venison is delivered to the landowner by agency staff.

All deer will be tested for CWD and held at a licensed meat processor until test results are returned. Deer that test not-detected for CWD are broken down and frozen into loins, roasts, and a bag of trim. Venison that is not distributed to landowners is donated to a local food bank for distribution to local food shelves.

All venison from a positive deer is disposed of at the University of Minnesota’s Veterinary Diagnostic Laboratory’s alkaline digester.

Why should DNR manage for CWD?

There is currently no known cure for CWD although research is underway. Aggressive management actions, such as culling, are short-term actions that help the long-term goal of keeping Minnesota’s wild deer herd healthy and hunting opportunities abundant.

Once the disease is established in a localized area, it is almost impossible to eliminate. But aggressive management actions can help to keep prevalence rates low and reduce further disease spread.

Allowing CWD to go unmanaged can result in very high prevalence rates and decrease deer populations in specific regions. Colorado and Wyoming already have documented population declines from CWD. High prevalence rates also can lead to decreased hunting opportunities, including lower bag limits, to maintain the population.

Additionally, recent studies in Wisconsin have show that deer infected with CWD are less resilient to other causes of death such as starvation, predators, vehicle collisions.

What can I do to help?

Thanks to culling and other management efforts, CWD remains a rare event for hunters in Minnesota. In the southeast, CWD is persisting. The DNR needs your help to keep CWD rare in Minnesota. By doing so, we are able to maintain a healthy deer population that current and future generations can enjoy.

As a landowner…
You may have access to additional positive deer that could be removed from the landscape. Allowing culling access would help reduce further transmission of this disease to other healthy deer. You also may consider a property management plan that allows the harvest of more deer, including does, during regular deer seasons and have them tested for CWD. If you notice any sick deer, report those to DNR.

As a hunter…
Keep hunting and get your deer tested for CWD. In areas where CWD is known to occur, we encourage hunters to keep hunting even if they’ve already filled the freezer. Venison donation programs offered by the Minnesota Department of Agriculture are available and it’s a great way to support your local community. If you notice any sick deer, report those to DNR.