Four gray wolves (Canis lupus) have been airdropped into Michigan for a very important assignment. The quartet, originally from Canada, has been helicoptered into Isle Royale national park to check the 2,300-square-kilometer island's moose population, which has exploded in the absence of the canine predator.
But the animals are there on a second mission. Wildlife specialists at the Ontario Ministry of Natural Resources and Forestry (OMNRF) hope their introduction will revive the island's wolf population – a conservation technique known as rewilding. The foursome (one female, three males) will be joining a pair introduced in September, and the OMNRF hopes to introduce a further 14 to 24 sometime over the next three to four years.
In the past, the Isle Royale national park was connected to the mainland via an ice bridge for 50 days of the year or more, allowing wolves to come and go more or less as they pleased. Now, thanks in large part to climate change, that ice bridge has become less dependable, effectively leaving any individuals on the island stranded. The result: the park's wolf population has dwindled. From a high of 50 in 1980, numbers dropped to a low of just two in 2016.
This has had an effect on the island's moose, whose population has boomed as wolf numbers have plummeted. It might not sound like a bad thing – at least as far as moose are concerned – but it can put a strain on resources. As large animals, moose can outcompete other herbivores for food. Previous population explosions have resulted in thousands of deaths due to starvation. OMNRF hopes this new project will change that.
However, actually finding the right wolves for the job is a trickier beast than it first appears. "You don’t get to choose the wolf you trap," explained John Vucetich, an ecologist from Michigan Technological University who leads Wolves and Moose of Isle Royale project, the Guardian reports. "It could be old, young, or injured when captured."
There is also the stress it puts on the animals, who are effectively being dumped in unfamiliar territory with complete strangers for company. "They live in families, so imagine what happens to a dog when they’re plunked into a foreign place," Vucetich continued. "They are being introduced to each other. It’s tense and nervous – and it’s tough to find food in a new place. It’s stressful."
As wolves are being reintroduced to Isle Royale, the federal government is reconsidering their protection under the Endangered Species Act (again). According to reports, the US Fish and Wildlife Service (FWS) is set to propose a rule to delist the animal, which was added during the 1970s when conflict with agriculturists caused populations to drop.
Gray wolves have already been delisted in Wyoming and were temporarily delisted in the Western Great Lakes area in 2011 before being readded in 2014. While the FWS says the proposal is an example of "one of our nation's great conservation successes", the Center for Biological Diversity calls it "a death sentence for gray wolves across the country" and plans to take the issue to court.
As for the Isle Royale wolves, things appear to be going well. "I am even more blown away by the resilience of these wolves who within hours after undergoing capture and handling and arriving on Isle Royale, immediately got on the trail of their pack mates," project manager Mark Romanski, Division Chief of Natural Resources for Isle Royale National Park, said in a statement.
"These large males, all around 90 pounds, will almost certainly know what to do when they encounter a moose."