Canadian wolves may be added to U.S. park service's work to revive island population

After years of dramatic decline, the wolf population on Michigan's Isle Royale National Park is finally growing, thanks to human intervention — and down the road, Canadian wolves may also help in the revival efforts.

In late September, the U.S. National Park Service began capturing and transferring wolves from the mainland to the island, which is on Lake Superior, not far from Thunder Bay, Ont. 

As of Tuesday, four adult grey wolves, captured on the Grand Portage reservation in northeastern Minnesota, had been moved to the island, said Phyllis Green, superintendent of the park.

Green said capturing and moving wolves is no easy task. 

"It is an amazing amount of work with some really great people that understand and know wildlife needs and how ... to do as safe a transport as we can," she said. "So it has been a unique and amazing experience."

Canadian wolves could add to genetic diversity

The hope is the new wolves will revive the park's wolf population. It had dwindled to just two inbred animals, and was in danger of being wiped out altogether on the isolated island — the site of a long-running study on the predator-prey relationship between moose and wolves. 

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Captured wolves are being carefully selected for transfer, said Green, and most that have been caught have not made the cut.

The animals must not only meet an age requirement, and pass medical tests administered by wildlife veterinarians before being moved, but they must also meet "distance criteria." 

"Basically they have to be far enough away from each other that we know that they're not part of the same pack," said Green. She said the population on the island must have broad genetic diversity.

This fall, wolves are being captured in Minnesota and Michigan, she said, but they may also look north of the border down the road. 

Discussions have been started with the province of Ontario about the possibility of adding Canadian wolves "into the mix," she said. 

"We would love to see Canadian wolves be part of this mix on the island ... because they never went through the loss of numbers towards extinction that we did in the U.S. They've remained a little more pure in their genetics. They have very little dog or coyote in them.

"So you have some pretty robust wolves on the Canadian side." 

Strategic release

The one male and three female wolves that have so far been moved to the island are being released in selected locations, Green said, as far as possible from the two wolves that were there before. 

The transfer comes with potential dangers for the animals. A fifth wolf had also been cleared for transfer, but died before that could happen. In a release, the U.S. National Park Service said the fatality sparked changes to protocols in an effort to reduce stress on the animals.

The relocated wolves are collared and being tracked by radio and satellite, Green said. 

The hope is to transport up to eight wolves from Minnesota and Michigan to the island this fall, said Green, but this is just phase one of the multi-year project. 

The park service ultimately plans to transport 20 to 30 wolves to Isle Royale.