WOLF WEEK: Inside the wolf den

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Seeing wolves in the wild is rare and difficult. Finding them at a spring den with pups, in the kind of rough terrain they prefer is even more challenging.

But the technology of GPS tracking by DNR wildlife biologists means finding a small hole dug in the ground is not impossible.

“This is what we come here for - just big enough,” said Mike Schrage, a wildlife biologist with the Fond du Lac Resource Management Division. “Some of them are down the hole and some of them started to squirm away.”

A den of wild wolf pups found in early May will shed new light on why half of them will not survive. The journey of gauging the health and numbers of Minnesota’s wolves begins in the cold of winter.

“They’re not always out in the open,” said Jason Jensen, a DNR pilot. “Sometimes they make you search for them, sometimes they present themselves quite openly.”

Using two airplanes, one that hones in on signals from radio-collared wolves and other carrying the researchers, the search begins. Jensen guides the crew over the forest canopy and frozen lakes near Grand Rapids.

That vastness of the forest, so evident from the air, is what makes piecing the puzzle of the wolf pack population into a number difficult. But one thing is certain, wolf numbers in Minnesota are increasing. By the last DNR count, about 3,000 live in this state. 

In the late 1970s, the home range for wolves was the southern edge of the Boundary Waters. Ten years later, their range had doubled. In the 20 years that followed, wolf packs extended down to Lake Mille Lacs and east. By last year, it increased a little more in all directions. Still, finding them is not easy.

“We look to hone in on a collared wolf,” said Jensen. “We get a loud enough signal that we can put eyes on the wolf.”

Eventually the tracker plane keys into a signal, finding two wolves walking out on a lake. With their path from the forest easily visible as they strolled out onto a frozen lake, they were seemingly unfazed by the plane passing overhead.

These wolves could be one pack of an estimated 500 packs that live out in the vast expanse. Many of which are denned up with pups now in the spring season. 

In many ways, the adult wolves mirror the litter the team located near Cloquet on the Fond du Lac reservation in early May. 

DNR and Tribal biologists work together to see each of these pups as a link to better understanding wolf life and death. Each year in Minnesota, 2000 wolves die, most of which are pups. The deaths can happen for a variety of reasons such as the parvovirus disease, starvation, accidents or occasionally other predators. When the adult wolf is away, a bear could come by and kill a pup that’s outside the den.

Understanding a wolf pup’s life, be it short or long, starts with basic statistics and identity. The team weighs and measures each of the four pups. Small numbered ear tags give them an identity and an identifying chip goes into a foreleg.

“So we’re inserting a pit tag right now, which is a permanent mark - kinda similar to what a lot of dogs and cats now have under their skin,” said Schrage. “Years from now, if we have this wolf in hand again we can just put the reader on it and read the tag number.” 

Wolf pups with ear tags and chips can be studied their whole life, providing key data for the research team in the years to come. 

Once tagged and identified, the researchers carefully place the pups back in the den, where they will be safe for when their pack returns.

The life or death of these grey wolves, and others like them now hinge on the harshness of wilderness from which they were born. For now, they belong to the protection of the den under the watchful eyes of their pack.

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