Wildlife managers and big game hunters have long suspected an interplay on the range between elk and mule deer, two native ungulate species trending in the opposite directions.

Many of the findings aren’t yet published, but the science is far enough along that the Wyoming Game and Fish Department is acting on it, and is in the process of identifying areas to knock down elk numbers in hopes of helping deer. Even a 5% downward swing in overwinter survival among female deer, Monteith said, can have a “legitimate effect on a population.” A fawn mule deer beds near the highway near Dubois in December 2021. For an adult female, that’s a pretty big deal.”Īnd for a mule deer herd it’s a big deal, too. “Two percentage points of body fat in autumn could influence overwinter survival by 10%. “How fat animals are plays a pretty key role in their survival,” Monteith said. The difference measured out to about two percentage points of fat gain - which can make the difference between life and death. In other words, the closer deer live to elk, the skinnier they get on average. Monteith’s remarks reflect preliminary data out of this lab that show a distinct inverse correlation between the amount of body fat female muleys gain during the summertime and their proximity to elk. We may not be able to have robust, large populations of elk and robust, large populations of deer.” “In this situation, with deer and elk, we may not be able to have our cake and eat it too.

“More is not always better,” University of Wyoming ecology professor Kevin Monteith told WyoFile. Our work is made possible by dedicated members like you who invest in our reporting - thank you!įindings emerging from an intensive, years-long Wyoming research project are beginning to substantiate suspicions that elk may be thriving on western landscapes at the expense of widely struggling mule deer. We appreciate you being a member of the WyoFile community.

Cow elk vs deer size