WORTHINGTON — Hunters who harvest a deer this fall in Nobles, Rock, Murray or Cottonwood counties are asked to help the Minnesota Department of Natural Resources with a study by donating the spleen from their harvested wild deer to a research project measuring the presence of neonicotinoids (neonics) in the deer population.

Neonics are the most widely used class of insecticides worldwide and are found in more than 500 commercial and domestic products in the U.S. They are present in a wide array of products used for insect control in homes, gardens, yards and crops, as well as on pets. A recent study by South Dakota State University found that captive white-tailed deer exposed to high levels of neonicotinoids, in a controlled setting, showed behavioral changes and also had reduced fawn survival.

In 2019, Minnesota DNR biologists conducted a statewide pilot study of wild white-tail deer harvested during the hunting season and found 61% of those submitted for analysis — from Minnesota’s southwest farmland area to the northern forestry region — had neonicotinoids present.

Eric Michel, DNR Farmland Region Deer Project Leader based in Madelia, said the 2021 study will take a more in-depth look in specific areas of the state. Deer permit areas 234, 237, 295, 296, 241, 214, 239, 240, 604, 172, 171 and 179 were selected for the study.

“In 2021, we are looking to confirm what we found in 2019,” he said, noting the focus will be on white-tail deer harvested from the 12 deer permit areas listed above, with a goal of increasing the sample size in those areas.

Newsletter signup for email alerts

“The permit areas we selected had high and low concentrations of neonics (in the 2019 study),” Michel said.

From the study, Michel said the DNR won’t be able to determine the health impacts neonicotinoids have on deer, but instead provide a better understanding of what the concentration levels are in wild deer.

How to register

Deer hunters are invited to take part in the study by requesting a sampling kit, which includes instructions on finding and harvesting the spleen, a YouTube link to view a video demonstrating the process, a bag for the harvested spleen and a postage-paid return box to ship the spleen — and a tooth from the deer — using the nearest UPS shipping location.

If the deer is harvested on a weekend, hunters can put the bagged spleen in the freezer and ship it during the week. Hunters will also be asked to complete a brief data collection form in which they will note the gender of the deer, approximate age — if they can determine that — and where the deer was harvested.

The spleens will be collected at the DNR office in Madelia for sub-sampling, and then shipped on to Michigan State University for further testing.

“We would hope to have data back by late spring or early summer next year,” Michel said.

The DNR has allotted 1,500 sampling kits for hunters who anticipate harvesting a deer from the four deer permit areas in southwest Minnesota.

Michel also noted that if someone doesn’t harvest a deer and had requested a sampling kit, they may give the kit to another individual who harvested a deer within the deer permit areas spleens are sought from.

Hunters who participate in the study will be provided with the results not only from the neonicotinoid study, but also learn the age of the deer they harvested.

Michel said knowing the age of the deer may shed additional light on the research, such as any relationship between the age of a deer and the level of neonicotinoids found in its spleen.

“We really rely on hunters to help us with this work,” Michel said. “It’s a really great opportunity for hunters to be a part of deer studies in our area, and it’s an opportunity for them to be involved in research and management.

To request a sampling kit, visit mndnr.gov/wildlife/health/neonic.html. Questions may be directed to Michel at eric.michel@state.mn.us or 507-578-8918.

Participants will also have a chance at winning a $100 Fleet Farm gift card provided by the Minnesota Conservation Federation, or two codes for a free pair of Irish Setter boots supplied by Back Country Hunters and Anglers.