A female wolf captured in the Grand Portage Band of Lake Superior Chippewa Forest was released on Isle Royale last week. While she left her cage when it was opened, her male counterpart who was released some distance away, stayed in his cage until almost nightfall before daring to venture out into his new home. Photo courtesy of the National Park Service
In an effort to restore a predatory/prey balance between moose and wolves on Isle Royale, and to reduce over browsing on the island by the moose, the National Park Service has decided to bring as many as 30 wolves to the island, which now has an estimated 1,600 moose and two aging wolves.
The capture and release of the first two gray wolves went well, but something went horribly wrong with the next capture.
Two gray wolves, a 4-year-old female and a 5-year-old male, were live trapped in the Grand Portage Band of Lake Superior Chippewa forest and were taken to the island on a U.S. Fish and Wildlife Service aircraft late in the day on Wednesday, September 26.
Those wolves were transported in crates to separate release sites away from the public and the territory of the two resident wolves. It didn’t take long for the female to leave the box and begin exploring her new home on the island. The reticent male left his crate after dark.
After the first successful release Isle Royale superintendent Phyllis Green said, “We have been planning this relocation operation with our partners and are very pleased with the progress so far. Releasing these two wolves on the island is the first step to restoring the ecological dynamics in the park. The assistance of all our partners is critical to the success of this effort.”
But the next day a captured wolf, a female, perished in the care of the NPS.
Per protocol, once trapped and caged, the wolf was sedated and transported to a holding facility for further medical examination. While in the holding facility, the wolf ’s physical condition deteriorated and it died, despite the best efforts of veterinarians attending to it.
Upon death, the wolf ’s body was taken to the University of Minnesota veterinary diagnostic lab for necropsy and diagnostic evaluation.
Following the wolf ’s demise changes were immediately made to the capture plan, including the length of time a captured animal is held before releasing it, as well as adjusting the sedation process which is used to reduce the stress levels of the caged wolves.
The first male and female wolves released on the island came from different pack territories on the Grand Portage Indian Reservation. Both wolves received medical examinations by National Park Service (NPS) wildlife veterinarian Michelle Verant and wildlife veterinarian Tiffany Wolf of the University of Minnesota before they were transported.
Both were found to be in good condition and apparently healthy.
Each wolf weighs approximately 75 pounds and has a thick coat of light tan, gray, and white fur with black markings, which is typical of gray wolves in the region. The wolves were vaccinated and fitted with GPS collars.
By the weekend the two wolves were spotted on game cameras set up to monitor a moose carcass left for the wolves. As part of the translocation efforts, moose carcasses were placed in specific areas on the landscape to provide initial nutrition and attract wolves to these locations while subsequent wolf translocations occur in different areas.
At different times both wolves, outfitted with GPS collars, visited carcass sites. The female remained in the vicinity of the carcass through the following morning and then moved northeastward and visited another location where the NPS stationed a moose carcass.
By Monday, the female’s GPS position indicated she had moved at least 12 miles into the interior of the island.
The NPS will use GPS collar data to determine how translocated wolves form social groups and visit kill sites to understand more about predation impacts, to keep track of individual life histories, and to confirm reproduction.
The collar signals from the male have not uploaded any data, which is normal for satellite monitoring startups, but he has been seen in game cameras and is moving around the island. The capture and translocation operations will continue in Minnesota and Michigan for the next several weeks.
NPS Midwest Regional Director Cam Sholly signed the Record of Decision for the Plan to Address Wolf Presence on Isle Royale National Park in June. 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.
On this project the NPS is collaborating with the Grand Portage Band of Lake Superior Chippewa, Michigan Department of Natural Resources, Minnesota Department of Natural Resources, U.S. Fish & Wildlife Service, U.S. Department of Agriculture Wildlife Services, U.S. Geological Survey, University of Minnesota, and multiple NPS units.
The NPS plans to monitor ecological conditions and other factors, such as predation rates, genetics, moosewolf ratios, and terrestrial and aquatic vegetation impacts to evaluate project success.
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