To cool off in the summer and avoid black flies, moose like to spend a lot of their time in bogs, swamps and lakes. They also feed off of the bottoms of these watering holes, receiving as much as half of their 9770 calorie per day (for a full grown moose) diet from aquatic vegetation. Moose throughout Minnesota have been dying off, and scientists are trying to figure out what is causing their decline.
Moose, Minnesota’s largest herbivores, are getting harder and harder to spot. And topping out at more than 1,800 pounds and standing 7 feet at the shoulders, that’s a hard critter to hide.
Twenty years ago there were more moose in Cook County than people. Now the herd has shrunk considerably.
In Northwestern Minnesota the news is far worse. In 1980 there were more than 4,000 moose, but by the early 2000s, there were barely 100. Last fall the count was 18.
So why the dramatic decline?
A team of international wildlife researchers is putting their heads (and data) together to solve that mystery.
And there is a mystery, because while scientists suspected that warmer temperatures could be playing a key role in the decline of moose, they aren’t so sure anymore.
That’s because, while moose are dying in alarming numbers in Northeastern Minnesota, they are on the increase in places like North Dakota, New England, parts of the Rocky Mountains and the Upper Peninsula of Michigan, areas that traditionally have warmer temperatures than northern Minnesota.
So if it’s not warmer temperatures, what’s killing the moose?
To help solve that mystery, a group of scientists embarked on a study this January where 63 moose located in northeastern Minnesota and northwestern Ontario were tranquilized and than outfitted with GPS satellite transmitters.
The moose were brought down by a tranquilizer gun shot from a helicopter. Once down, blood was drawn, pellet and hair samples were taken, and winter ticks were collected (if present) from the sleeping animals. After about 30 minutes the animals woke up and ambled off.
Researchers include personnel from the Ontario Ministry of Natural Resources, the 1854 Authority, the National Park Service and the Natural Resources Research Institute.
Funding for this $1 million research program came from the Legislative and Citizens Commission on Minnesota Resources, the National Park Service, the Fish & Wildlife Services, and the Ontario Ministry of Natural Resources.
Ron Moen, a research scientist with the Natural Resources Research Institute (NRRI) at University of Minnesota Duluth, said that calves have been dying in disproportionate numbers.
One of the things that Moen and others have learned is that after birthing a calf (or calves) the cow will stay in an area no bigger than 200 to 375 yards for the first three weeks following birth.
“If the (radio-collared) cow moves out of the area too soon we will know that something is wrong” said Moen.
But whether or not someone can always get to the location is another matter. Research staffs are small. Moen has a graduate assistant and few dollars to truck out into the woods in search of a missing calf.
“There aren’t many grant opportunities out there that enable any of us to implement a research project at the scale we would like,” said Andy Edwards, director of the Research Management Division for the 1854 Treaty Authority, who added, “But by successfully obtaining grants to implement projects specifically tailored to our individual needs— and then working together to share the information we collect across a broad geographical area, varying moose densities, and management objectives—we’re able to get at reaching our goals and increase the data we all have access to, and perhaps most importantly to get that many more entities together in meeting our common vested goal of benefiting moose on a broad scale.”
Edwards said the collars that were deployed this January “are programmed to collect GPS locations (20 minute intervals), ambient temperature (once a minute), and moose activity level (neck movement of moose in three dimensions every minute) for approximately two years. The collars are programmed to drop off in early 2013 so we can recover them and retrieve all of the stored data.”
While the collars are working well, Moen said, “We have found that we don’t need data every minute from every collar. We don’t have time to analyze all of the readings. But we didn’t know that when we set up the study.”
Still, too much data is better than no data. And with funding getting harder and harder to get—the Minnesota legislature denied a $500,000 grant for further study of moose this past winter—researchers are happy to have what funding they have.
Some of those 63 collared moose are in Cook County. According to Mike Schrage, wildlife biologist with the Fond du Lac Band, “Eleven moose were collared on the Grand Portage Reservation. In addition, six were collared around the Gunflint Trail, 19 in and around Voyageurs National Park, six in Quetico Provincial Park and 21 in the Isabella area. In addition, there are 34 moose from research that began in 2002 still wearing radio-collars in the Isabella area.”
Seth Moore, biologist for the Grand Portage Band of Lake Superior Chippewa, said, “The intent of the study is to identify habitats actively being used by moose during all four seasons, so that similar habitat types can be developed and managed into the future. This study was developed to ascertain habitat use throughout a time of changing climate.
“Our long-term goals are to develop forestry management plans to develop, protect, and maintain quality moose habitat,” said Moore.
In Grand Portage 47,000 acres are being managed for moose, and the Forest Service is managing 40,000 acres in the Lima Green area near Greenwood Lake.
Estimates vary about how much the moose herd has shrunk in Grand Portage, but, according to Moore, “The population estimate for 2005 approached 80 animals. As a disclaimer, I must say that the variability in survey results from year to year makes population estimates vary greatly and although our estimates indicate a 64% drop, I would take that estimate with at least a 25% grain of salt. I can say confidently that the population has dropped, but am less confident in the actual percentage drop.”
When Schrage was asked about the decline of moose in Cook County he responded, “We don’t estimate moose numbers on a county basis, but for the entire northeast moose herd, the numbers have dropped from approximately 8,000 in 2005 to 5,000 in 2011. That’s about a 38% decline. Numbers have appeared to decline the most along the western edge of moose range in St. Louis County. While numbers are likely declining in Cook County as well—it remains some of our best moose country in the state.”
This is Part 1 of a three-part series on Minnesota’s Moose.
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