ISLE ROYALE, Mich (KMSP) – Isle Royale sits like a gem in a cold ring of Lake Superior water, some 15 miles off the shore of Grand Portage, Minnesota. Its isolation has been key to the island’s preservation. It sits today as a national park, not much different from when Norwegian fisherman built the first fish camps on its shores in the mid-1800’s.
A pristine island of some 210 square miles, it was a privilege to visit. To see the young bull moose swimming across a bay on our boat trip in or to come face to face with this cow moose freezing us in our steps on an island trail, was to experience nature unencumbered by man.
Time spent on the island allows you to slow down and think of the world in simpler terms. That is until you consider the very complicated national debate over reintroducing wolves to Isle Royale.
Ice bridges during the cold winter months enabled the first grey wolves to find the island 75 years ago, and they stayed, because they found food in the moose population.
Over the decades, the predator/prey populations ebbed and flowed. It was a forest ecosystem that worked; scientists studied it, but for the most part, did not interfere.
Then, the ice bridges stopped forming, and the wolves, after peaking at a population of 50, started dying. Canine Parvovirus took many, while wolves killing other wolves took some. They died at an alarming rate. Conversely, the moose, with fewer canines to hunt them down, grew in numbers of an equally alarming pace.
Today, more than 1600 moose roam the island. Now, with only two aging and non-breeding wolves left to hunt them, the National Park Service is wrestling with whether man should step in and change the course of nature. The NPS is also struggling with the relative “do not touch” scientific philosophy of Isle Royale and what re-introducing a new pack of wolves, taken from the mainland, and deposited on the island, would mean.
A career spent studying Isle Royale
Rolf Peterson, a research biologist at Michigan Tech., was a 22-year-old graduate student when he first stepped foot on Isle Royale. There is not a trail, and barely a tree, he doesn’t know. Peterson is known around the world for his wolf and moose research conducted on the island. No one knows more about the connection between a healthy wolf population, healthy moose population and a healthy island than Peterson does.
Peterson has spent 50 years of his life studying the predator/prey balance, and says the dynamic has clearly changed. The moose population is trending up rapidly and, in his view, doing nothing would be disastrous for the ecosystem.
“The moose will destroy the forest. It will take several decades and several ups and downs of population eruptions and crashes of moose, but basically the forest as we know it would disappear,” Peterson said.
Moose love balsam fir, it’s a major food source and the main tree of the island. These enormous herbivores will eat every seedling in sight. Peterson pointed us to the western part of Isle Royale where over the decades moose have over grazed the area. Today it is a barren spruce and grass environment, and that, Peterson says, is what most of this national park would become with a moose “only” ecosystem.
Peterson believes reintroducing wolves will help bring the moose population back down to a more manageable level.
“The main issue here is there’s a moose population that’s like a runaway freight train right now, and if we let it runaway, it will be to the detriment of the entire national park.”
Unsustainable wolf population
Scientists and the NPS agree, the two remaining wolves at seven and nine years old will not live much longer and cannot affect a moose population that will likely double inside of five years. Leaving the NPS to decide who knows better: Man or Mother Nature.
The NPS this week signaled there does seem to be movement, not only toward a decision, but also toward reintroducing wolves. Officially releasing this statement:
“NPS is currently producing a final environmental impact statement with a preferred alternative to re-introduce wolves to the island. This alternative would provide a large enough number of wolves with the goal of establishing a healthy population that functions as an apex predator. A decision is expected after the document is released for public view.”
The NPS is expected to make a decision in the next few weeks.