DNR’s annual aerial survey shows Minnesota’s moose population stable
For the ninth year in a row, Minnesota’s moose population remains relatively stable, but reproductive success – one of the factors that has the greatest impact on moose survival over time – remains low.
This winter, the DNR estimated the moose population to be 3,150 animals (between a range of 2,400 and 4,320). Due to the variance in this type of annual population estimate, this year’s estimate does not suggest a decline from last year’s estimate of 4,180 moose.
This year 308 moose were observed on 39 (75%) of the 52 plots surveyed (a total 723 square miles), less than the 429 moose observed on 43 of 52 plots during the 2019 survey. This year’s 308 observed moose included 131 bulls, 138 cows, 37 calves, and 2 unclassified adults
The survey provides an estimate rather than documenting the precise number of moose because biologists cannot see or count every moose across the 6,000-square mile survey area. They survey a portion of the moose range every year to generate the estimate.
While the recent population stability is good news, DNR researchers point out that Minnesota moose remain at risk over the long term. The moose population has declined 64% from an estimated 8,840 animals in 2006.
Low reproductive success and continued deaths from brainworm and other diseases make it difficult for Minnesota’s moose population to recover.
Two helicopters are used to conduct the survey. Observers determined the sex of moose using the presence of antlers or the presence of a vulva patch, nose coloration, and bell size and shape. They identified calves by size and behavior.
Two primary strengths of this aerial moose survey are the consistency and standardization of the methods since 2005 and the long-term consistency of the survey team’s personnel, survey biometrician, and geographic information system (GIS) specialists.
Both the Fond du Lac Band of Lake Superior Chippewa and the 1854 Treaty Authority contributed funding and personnel for the annual survey. The survey is available on the DNR’s moose management page.