Efforts to repopulate Isle Royale with wolves appear to be succeeding, according to an annual report from Michigan Technological University.
Just four years ago, only a single pair of inbred wolves remained on Isle Royale. That’s when the National Park Service began transplanting outside wolves to the isolated island. Now, Michigan Tech’s annual survey reports an estimated 28 wolves on the island as of this past February.
“Overall, the new population of wolves on Isle Royale appear to be well-established and functioning healthily,” the report says.
They’re also reproducing. The researchers found evidence that five litters have been born to the island’s two packs since 2019.
Michigan Tech researcher and assistant professor Sarah Hoy said the Isle Royale wolves are “doing everything that they should be doing” and now comprise a “healthy population” for the island.
Hoy said the latest report shows that wolves are “really resilient animals” that can form functional communities shortly after reintroduction. “It just goes to show how quickly the population can be found to thrive in the absence of human persecution,” she said.
Hoy said wolves are also critical to Isle Royale’s ecosystem. That’s particularly true when it comes to controlling the moose population, which exploded in the near-absence of their natural predators and wreaked havoc on the island’s forests.
The report found that Isle Royale’s moose population decreased 28% from 2020-2022, to about 1,346 animals. Hoy said there’s evidence that wolves are part of that decline, but that other factors, including malnutrition from forest reduction and parasitic winter ticks, have also contributed.
