Wolf No. 3 being released at Isle Royale National Park/NPS Jim Peaco

Two more wolves were moved to Isle Royale National Park this week as efforts continued to ensure predators would be on the island to counter the burgeoning moose population there.

On Tuesday, a she-wolf was transported by the National Park Service boat BEAVER from Grand Portage, Minnesota, and released in the park. Two days later, another female wolf was flown by the U.S. Fish and Wildlife Service to the island and carried by park staff over a hiking trail to the release site. This brings the total number of wolves relocated since Sept. 24 to four. 

Late last month a 4-year-old female and a 5-year-old male were set free in the park after being flown to the park by the U.S. Fish and Wildlife Service. A few days later, a female wolve died after being sedated after it was captured for relocation.

The wolf released on Tuesday this week weighed approximately 70 pounds and showed signs of having had pups in the past. The veterinarians estimate that she is 5 years old.  Distinguishing her slightly was the black coloration on her back. Once on the island, the wolf waited in the crate for less than an hour before walking away. Two days later she was seen on one of the park's remote wildlife cameras. The Park Service plans to release those photos at a later date.

Securing wolf on NPS Beaver for trip to Isle Royale National Park/NPS, Alex Picavet

On Thursday, an approximately 2-year-old wolf weighing 51 pounds was released. She remained in the transport crate until Friday morning before silently slipping away between monitoring checks by park personnel. 

Under a plan adopted earlier this year, up to 30 wolves are to be set free at Isle Royale over the next three years under a plan the National Park Service has settled on in a bid to bring genetic diversity back to the park's few remaining wolves. This fall they hope to move six wolves to the island.

Chronic inbreeding has impacted the health of Isle Royale's wolf population. There was hope that "ice bridges" that formed between the Lake Superior island and the Canadian mainland during the winter of 2013-14 would enable wolves to arrive from Canada with new genes. But no new wolves reached the island, while one female left and was killed by a gunshot wound in February 2014 near Grand Portage National Monument.

The goal for this fall is to translocate up to six wolves from the Minnesota and Michigan mainland to the park. This is the first phase of a three- to five-year effort to relocate up to 20-30 wolves to the isolated island park. Researchers recommended this number of wolves to establish adequate genetic variability to help accomplish the overall goal of restoring predation as a key part of the ecosystem on the island. 

The NPS plans to monitor ecological conditions and other factors, such as predation rates, genetics, moose-wolf ratios, and terrestrial and aquatic vegetation impacts to evaluate project success.

Trapping and relocation operations are expected to continue in Michigan and Minnesota for the next two weeks.