ISLE ROYALE, MI – Two years ago this winter, after an arctic blast had frozen the surface of Lake Superior between Isle Royale and the Canadian mainland, a 4-year-old female wolf walked to the edge of Michigan’s most remote island after sunset. She took a few steps onto the ice … and kept going. About 15 miles later, the 70-pound wolf who sported a distinctive black fur mantle across the back of her tan coat, stepped onto the Canadian mainland, her GPS tracking collar showed.
And with that one freezing, unexpected walk on Jan. 31 2019, the wolf known as W003F largely took herself out of the world’s longest predator-prey study that’s been going on for decades on Isle Royale.
The wolf had been captured in nearby Minnesota in the fall of 2018, and spent nearly four months on the island archipelago before trotting back to the mainland. Of the nearly 20 wolves who have been captured and brought to the island as part of an ambitious National Park Service project to resurrect viable wolf packs there and thin the moose population, W003F has been the only wolf to use an ice bridge as an escape route.
Even though she was no longer a prime part of the island’s wolf project – no one was tracking her to see which wolves she traveled with or if she mated and had pups – researchers for the last two years have been keeping an eye on this wolf’s distant movements through her radio collar. And what they’ve seen has really surprised them.
“She’s crossed a lot of borders,” said Beth Orning, a postdoctoral research scientist who until recently worked on the Isle Royale project as part of the Global Wildlife Conservation Center through the State University of New York’s College of Environmental Science and Forestry.
A plot of W003F’s radio-tracked movements show that once the wolf reached the Canadian mainland in early 2019, she traveled back into Minnesota – near the area of her capture – and stayed there for about a month. “She continued traveling around Minnesota and into Ontario, Canada, until deciding to remain in Ontario from July to September 2019. From September to October 2019, wolf 003F ventured back to Grand Portage Reservation (in Minnesota) for a month. This stay was brief before she traveled back up to Ontario. Although she has spent most of her time in Ontario since October 2019, she did make two excursions to Voyageurs National Park in Minnesota during February and March 2020,” study staff said. Her journey has covered thousands of miles.
All this long-distance roaming makes her a rare wolf, scientists say. Most wolves travel to find a mate or join an existing pack. But W003F’s preference to be on the move and cover a lot of ground is not something researchers see every day. “The total amount of distance and where she traveled, it’s in the rare spectrum,” said Orning, one of the authors of a scientific paper published recently, entitled “Emigration and First-Year Movements of Initial Wolf Translocations to Isle Royale.”
BROUGHT OVER ON A BOAT
The female wolf started her journey to become W003F on Sept. 29, 2018, when research documents show she was captured using a foothold trap while walking within the Grand Portage Reservation in northeastern Minnesota. She was one of a handful of wolves captured there. Some were destined to head to Isle Royale, while others were deemed unsuitable for the project and released. “In each area, we pre-baited sites with nuisance beaver and vehicle-killed white-tailed deer carcasses to facilitate captures,” project staff wrote.
W003F taking her first step out of her crate onto Isle Royale in October 2018.
Once this particular wolf was caught, researchers determined her age and physical condition made her a good fit for relocation to Isle Royale. After her vet check, she received a round of vaccinations, ear tags and a GPS collar. With that, she became W003F. On Oct. 2, she was loaded into a large metal crate, which was covered with a tarp and lifted onto the Beaver, a National Park Service boat, for the trip to the island. Once there, her crate was moved from the boat onto the back of a John Deere Gator, and driven to the release site near Windigo, on the southwest end of the island. Less than an hour after her crate’s door was opened, she edged out and gave the project crew a beautiful last photo of her walking into the woods.
In her first days, she would have had food available as she settled into the island. Researchers had provided freshly-killed moose from the island’s over-abundant population, giving the new transplants a taste of the big prey the park service was hoping they’d become adept at killing themselves. A couple other translocated wolves had already been dropped off on the island, and its last native-born pair still roamed one side of Isle Royale.
INTERNATIONAL ADVENTURE
Her early movements “encompassed the entire island,” researchers said. Until Jan. 31, 2019. About that time, a dip in the Polar Vortex sent arctic air spilling down into the Great Lakes. Temperatures and wind chills plummeted. Enough of Lake Superior’s surface froze to create one of the infrequent ice bridges between Isle Royale and the mainland.
Isle Royale researchers said an ice bridge departure had been on their radar as a possibility, but it was still a disappointment to lose one of the project’s wolves that way.
“Ice bridges are always a possibility,” Orning said. “We really don’t know when they are going to form and when they’re not,” adding climate change has made them less predictable.
Researchers tracking the new wolves from afar via their GPS collars first noticed a discrepancy with all the new wolves’ tracking data during that Polar Vortex stretch. The NPS described it this way in a press release at the time:
“Mark Romanski, Isle Royale National Park’s Division Chief for Natural Resources and project lead for the wolf reintroduction efforts, had been monitoring GPS data from each of the translocated wolves ... . He noted the wolves had been moving about the southwestern end of the park. However, no locations were reported for nearly 5 days, between Jan 27th and Feb 2nd. This can happen when a wolf is hunkered down in dense forest cover and there is no clear view for the collar to transmit data up to the satellites. Blinded by the poor satellite transmissions, the park needed aerial observations to help locate the translocated wolves.”
On Feb. 2, 2019, Rolf Peterson and other researchers from Michigan Technological University – where the island’s wolf-moose study has been based for decades - arrived on Isle Royale. He quickly arranged to go up with a pilot so they could radio-track the new wolves from the air. They found signals from two of the three collared wolves that were supposed to be on the island at that time. As for W003F, Peterson caught a very static-filled signal radiating from off Isle Royale’s north shore toward Canada.
Wolf 003F left Isle Royale via an ice bridge across Lake Superior on Jan. 31, 2019. She crossed onto mainland Canada near the U.S. border with Minnesota.
“We followed the signal toward the north shore of the island and finally out over the open water of Lake Superior,” Peterson said at the time. “A lead a half mile wide had opened a few hours before, as the ice bridge was dislodged by a strong northeast wind. We flew out across the open lead and out over the ice pack then determined that the wolf’s signal was still to the north, straight to the mainland.”
Later that day, GPS data from the wolf’s collar came in, showing she’d headed north off the island, then cut a track west across the frozen lake, stepping into Canada near the Pigeon River and the U.S. border of northeastern Minnesota.
While researchers can’t get inside this wolf’s head and pinpoint exactly why she decided to risk leaving the island, they do know her GPS collar had showed decreased movement in the days before she left. That might show she was avoiding other wolves on the island.
“We posit food stress, social competition, and lack of breeding opportunity, or a combination of these and other factors may have facilitated the long-distance emigration of this wolf from Isle Royale.”
W003F's movements since she left Isle Royale in early 2019. She has traveled thousands of miles, crossing into the U.S. and then back to Canada.
In the months and years that followed, Orning said researchers kept an eye on the GPS data W003F’s collar kept sending back. Her far-flung movements implied she had not found a mate or integrated into a pack. Her preference seemed to be to stay on the move. Researchers saw that she traveled 1.5 times faster than other collared wolves on Isle Royale once she left.
Her recent locations have been around Atikokan, Ontario and the forests at the outskirts of Thunder Bay.
“She’s a Canadian now,” Orning said.
Even more than that, W003F has returned to the way she started – an untracked wolf. Her GPS collar failed at the end of December, Orning said. Where she goes next is up to her.
Wolf 003F's movements from October 2018 through September 2019.
READ MORE
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