The Decline of Northeastern Minnesota’s Moose Herd

Over the last several years, fewer moose sightings and increased reports of dead, emaciated moose have fueled suspicions that the northeastern Minnesota moose herd is declining. According to a recent article by Gustave Axelson in Minnesota Conservation Volunteer, a 6-year DNR study of radio collared moose in the Isabella area has confirmed these fears. Of 116 collared moose, 85 died; of those, 49 died of unknown causes. That’s 21% - well over the average mortality rate of 8-12% across most of North America.

The term “tip over disease” has been adopted by many to refer to these mystifying deaths because the moose appear to literally just fall over. But as the article explains, it’s unlikely that a single disease is to blame. They’re more likely the result of several diseases that on their own might be survivable but together wear down moose under stress. And the moose of northeastern Minnesota certainly appear to be under stress.

Axelson reports that Moose thrive in cool climates with snowy winters. When the temperature is too warm in summer or winter, they suffer from heat stress. Evidence suggests that as we have seen more “heat stress days,” their survival rate has declined. As a result, the suspected culprit behind the decline of the Minnesota moose shares a familiar refrain with many ecological conversations about northeastern Minnesota: climate change.

To learn more about the study and what can be done read the complete article at Minnesota Conservation Volunteer >