Moose population showing signs of life

by Jesse White
Mesabi Tribune
TOWER — There was a time not too long ago when state wildlife biologists wondered if the rapid decline of the moose population in northeastern Minnesota would ever slow down.
After peaking at an estimated 8,840 animals in 2006, the population in Minnesota’s Arrowhead region plummeted over the next several years.
In 2014, the DNR estimated the population to be approximately 2,760, down 35 percent from 2012 and 52 percent from 2010.
At the time, scientists suspected some combination of higher temperatures, parasites, diseases and changing habitat were the cause of the mortality officials were seeing.
That same year the Minnesota DNR canceled the moose hunting season, which hasn’t returned since.
At that point 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 bears were killing large numbers of moose calves.
A state moose management plan was implemented in 2011.
Today, DNR officials say the population has not only stabilized, but according to results of the latest aerial survey done this winter, there is reason to be optimistic about the future.
Among its findings, the 2022 survey estimates the moose population at 4,700, statistically unchanged from the last survey in 2020 but the highest since 2011, when the population was midway through a steep decline.
The estimated calf-cow ratio this year was 45 calves per 100 cows. The percentage of calves and the calf-cow ratio are the highest since 2005, when the population was near its peak and considered healthy, the DNR said in a statement.
“Both factors are indicators of potential improvement in reproductive success, which has a positive impact on population numbers,” researchers said.
The 2022 moose survey was conducted through overflights of about 6,000 square miles of the northeastern quarter of the state by helicopter in early January. The DNR uses computer modeling to translate moose sightings into wider population estimates.
The aerial surveys have been conducted each year since 1960.
The Fond du Lac Band of Lake Superior Chippewa and the 1854 Treaty Authority helped pay for and staff the annual population survey.
Moose are found throughout the northern regions of the United States, and according to wildlife data there are approximately 300,000 moose in 19 states including: Alaska, Colorado, Connecticut, Idaho, Maine, Massachusetts, Minnesota, Montana, Michigan, Nevada, New Hampshire, New York, North Dakota, Oregon, Utah, Vermont, Washington, Wisconsin, and Wyoming.
Two-thirds of the U.S. population of moose is found in Alaska.
There are an estimated 500,000 to 1 million moose in Canada.
Penny Backman, acting DNR wildlife manager for the Tower area, said despite the results of the survey and recent sightings locally near the Sax-Zim Bog and other places, her office hasn’t seen an increase in reported activity.
“I am not really hearing about additional moose sightings. We have pockets of moose surviving in areas outside of the official moose range. They have always been there, just not in sufficient numbers that we are counting them,” she said, adding that there is no real explanation as to why the population has stabilized over the last few years.
“We have no really “solid” ideas as to why the moose population is stabilizing. It could be the larger fires creating better habitat locally, weather, or lower deer populations limiting parasite spread. However, we just don’t know for sure at this time,” she said.
And while the DNR described the January survey results as good news and said researchers were optimistic about the immediate future, the agency also cautioned that moose numbers are 47 percent below their 2006 peak and that the animals still face long-term risks.
Nancy Hansen, Area Wildlife Manager for the Two Harbors area, has taken part in the aerial survey for a number of years, including this year.
It was canceled last year and there were some changes in 2022, she said.
“(Former) Tower Area Wildlife Manager Tom Rusch and one of our long serving DNR Pilots, John Heineman, both retired in 2021, so we filled their spots with another experienced DNR helicopter pilot and other experienced observers (DNR Wildlife and 1854 Treaty Authority staff),” Hansen said. “Although we fly a 10% sample of the 436 moose survey plots in the moose range, they are selected at random and will vary as to whether or not they’ve been flown before,” she said. “Some were flown for the first time in 2022, while others have been flown multiple times over the years. We also fly permanent habitat plots every year.”
In the past it was nine, she added, three each of wildfire, prescribed burns and forest management/harvest habitat, but this year they added another plot in the Greenwood wildfire area.
“Moose generally don’t use wildfire areas at first, but once vegetation starts coming in, they will. So hopefully that big fire will produce some good moose habitat in the future. I will say that our percentage of moose calves compared to the adults was higher this year which is always a good sign,” Hansen said. “Other than that, comparing the actual number of moose we count from one year to the next doesn’t mean much because we fly different survey plots each year.”
The survey took place between January 6-14 this year. Hansen said they try to fly the survey in early January each year so long as we have adequate (eight inches or more) snow cover across the moose range.
Hansen said she doesn’t want to speculate too much because one year is just a snapshot in time — it takes years to show how a population is really doing. But, she added, that between the wildfires and project work, the Moose Habitat Collaborative is doing, a lot of good moose habitat development is taking place.
“I also know that our deer numbers are low right now across much of the moose range which can help reduce moose exposure to parasites like brain worm and liver flukes on the landscape,” Hansen said. “Winter Ticks are still a moose specific parasite that can weaken and cause poor health in moose when large numbers of ticks are feeding on individual moose, but the more snow we have on the ground in the springtime (in moose range), the less likely the winter ticks are able to survive and increase their numbers when they fall off moose and land on snow.”