Climate Change Is Killing The Wolves Of Isle Royale

When it comes to the wilderness of Isle Royale National Park, located in the northwest corner of Lake Superior, the wolves have always had the run of things.

Only accessible to humans by boat or seaplane, Isle Royale is the least-visited national park in the continental United States. Last year, only 16,746 visitors made the journey.

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Isle Royale National Park. The least visited National Park, the population of 1200 moose exceeds the number of people for most of the year. The park preserves 132,018 acres of land-based wilderness. Photo via Getty.
But climate change is threatening the wild wolves who once lived with moose in blissful solitude in this remote preserved land, many say. Ice bridges once connected Isle Royale to Ontario, allowing animals to cross back and forth almost every other year.

Since scientists began keeping records in 1973, ice accumulation in the Great Lakes has declined by 30 percent. An ice bridge may only form once every 15 years now. Lake Superior is warming faster than any large lake on the planet.

With an ice bridge becoming increasingly rare, those wolves have become “critically isolated,” the Detroit Free Press reported. As many as 50 once roamed the island, though scientists think 25 is a more reasonable baseline number, according to the Wildlife News.

Only eight adult wolves are left. Two or three pups may have been born this summer.

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In this photo released by Michigan Technological University, a gray wolf is shown on Isle Royale National Park in northern Michigan, Feb. 24, 2006. (AP Photo/Michigan Technological University, John Vucetich)
The wolves’ and moose hunter-hunted relationship is the longest continuous study of any predator-prey system in the world. The park’s research project notes how uncharacteristically warm temperatures can greatly disturb the balance between moose and wolf pack populations on Isle Royale:

Then, a series of very hot summers struck. During hot summers moose feed less, as they spent more time resting in the shade. Having fed less, the undernourished moose were less prepared to survive the winters. Warm temperatures also enabled severe outbreaks of moose tick. Weakened by heat and ticks, moose dropped to their lowest observed levels. Wolves took advantage of weakened moose, fueling high rates of predation. During the first decade of the 21st century, the moose population steadily slid to its lowest levels.The wolf population, with 30 individuals living in three packs, had been thriving until 2006. But with moose becoming increasingly rare, capturing food become increasingly difficult. One wolf pack failed after another. By 2011, the population was reduced to 9 wolves living in one pack and another half dozen wolves, the socially disorganized remnants of Middle Pack. DNA analysis of wolf scats collected at kill sites indicates no more than two adult females in the population. If they were to die before giving birth to new females, the wolves would be committed to extinction.


Those wolves who are left are suffering, the Detroit Free Press says. Generations of inbreeding, with no ice bridges to introduce new wolves to the island, have bred genetic deformities in the animals. The deformity gives them misshapen, heavy backs and makes breeding even more difficult.

Some have called for the National Park Service to introduce new wolves into the dwindling Isle Royale pack.

It would be the first time the National Park Service has ever taken deliberate action determine the fate of a species at one of its parks. Whether that role belongs to the Park Service has ignited debate in the scientific community.

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A gray wolf is shown on Isle Royale National Park in northern Michigan, Feb. 24, 2006. (AP Photo/Michigan Technological University, John Vucetich)
“Is it the Park Service’s role to feed science if it isn’t consistent with managing native species?” wondered the NPCA Park Advocate. Dr. Dave Mech, who previously researched the wolves on Isle Royale, told the Park Advocate he’s not convinced the wolves will go extinct and thinks officials should “wait and see.” From an evolutionary perspective, moose and wolves are relative newcomers to the island. Many believe nature alone should deliver the fate of the island wolves.

But John Vucetich, a researcher on the island, says that a genetic rescue is critical — not only for animals, but the entire Isle Royale ecosystem, designated a protected biosphere reserve in 1981 for its pristine lake forest wilderness.

“The one thing on which there is universal agreement,” Vucetich told the Detroit Free Press, “is that wherever there are large ungulates like moose or deer or elk, there needs to be a top predator to maintain ecosystem integrity.”

One Republican Congressman, Sen. Tom Coburn, thinks Isle Royale isn’t worth the money spent to keep it open, wolves or no wolves. In his report, “Parked: How Congress’ Misplaced Priorities Are Trashing Our National Treasures,” he blasted Isle Royale and other remote national parks, like the Upper Peninsula’s Keweenaw National Historic Park, as some of the “more egregious, wasteful or otherwise questionable expenses” to be found in America. Isle Royale has an annual operating budget of $4.35 million, according to the report.