Deep in the woods of Voyageurs National Park, on the remote Kabetogama Peninsula just south of Rainy Lake, a small and isolated moose population is surviving, even as others in Minnesota have been cut in half or wiped out.
The moose inside the park have been dealing with the same challenges as those outside it, from disease to predators to warming temperatures, yet their numbers today are almost identical to what they were in the early 1990s. The question is, why?
A team of wolf researchers, which has been painstakingly documenting every summertime kill and meal for wolves in the park, believes the answer may be because Voyageurs moose have a robust ally -- or, perhaps, a sacrificial pawn -- that others don't: American beavers.
Beaver numbers are so strong inside the national park that they've become the primary food for many of the park's wolves in the summer. It's possible that the beavers, once hunted to the brink of extinction, are keeping the wolves fat and happy enough that the predators don't need to eat the moose or their calves, said Tom Gable, project lead for the Voyageurs Wolf Project, a group of researchers with the University of Minnesota and the National Park Service studying summer wolf habits.
There are no easy meals in the wild. "But, relatively, it is much easier for them to catch a beaver than to risk getting kicked by a moose," Gable said.
With fewer calves being eaten, a higher percentage of moose may be living long enough to breed, keeping numbers stable even as the population deals with the same threats and diseases that plague moose in the rest of the state, Gable said.
The surprising thing is that Voyageurs has a relatively large wolf population. But, for whatever reason, the wolves inside the park almost never eat or kill moose in the spring and summer, when calves are at their most vulnerable, Gable said.
"We've tracked and found over 800 kills of beavers and deer fawns and everything else wolves are eating," Gable said.
Out of all of those kills, only three were moose.
A tempting alternative