Numbers stable, but Minnesota's moose aren't out of the woods
For the ninth year in a row, results from an annual aerial January population survey suggest that moose numbers in northeastern Minnesota continue to hold steady, following a precipitous drop in the animal’s population a little over a decade ago.
The Minnesota Department of Natural Resources estimates there are about 3,150 moose in the state, with a range of 2,400 and 4,320.
Researchers say the results are statistically unchanged from last year’s estimate of 4,180 moose, or 2018’s estimate of 3,030.
"And that's really good news,” said DNR moose team leader Glenn DelGiudice. “That makes us feel fairly optimistic. But on the other hand, the past survey results and this year's survey results do not forecast what we're going to see in the future."
Grow the Future of Public Media
MPR News is Member supported public media. Show your support today, donate, and ensure access to local news and in-depth conversations for everyone.
In the long term, DelGiudice and other researchers say Minnesota’s moose remain at risk.
After peaking at an estimate of 8,840 animals in 2006, the moose population in the Arrowhead region of the state plummeted between 2009 and 2012.
A landmark mortality study launched by the DNR found that parasites like brain worm and winter ticks, infections and wolves were responsible for the majority of adult moose deaths. Wolves and bear were killing large numbers of moose calves.
Despite the leveling off of the population, DelGiudice says those challenges still persist. He said adult mortality is still high. And he said the number of moose calves that survive to be a year old — called “recruitment” — remains low.
“In order to grow or to have a recovery of this population, we not only need to have a lower mortality of adult moose, but we also need to have good reproductive success and higher recruitment of moose calves to add to the population each year,” he said.
Researchers have found that female moose in Minnesota are still getting pregnant in high numbers. That indicates they are getting plenty of nutritious food to eat before going into rut in the fall.
But during a three-year study of calf mortality, DelGiudice and his colleagues found only about one-third of baby moose survived to be a year old. Of the calves that died, wolves were responsible for killing about two-thirds of them.
DelGiudice also said the survival of adult moose, especially females, isn’t quite as high as researchers would like to see. He said the survival rate of adult moose in Minnesota is around 85 percent; that should be closer to 90 percent in a healthy population.
The Fond du Lac Band of Lake Superior Chippewa and the 1854 Treaty Authority helped pay for and staff the annual population survey.