By GARRETT NEESE , Houghton Daily Mining Gazette
HOUGHTON – The two wolves left on Isle Royale will probably survive the winter, said Rolf Peterson, a research professor who helps run the annual wolf-moose study at the island.
Producing a healthy offspring is another story.
Years of inbreeding among the island’s population has left only the male-female pair. But they’re father and daughter. And half-siblings who share a mother.
“Wrap your head around that,” Peterson said. “You’ve got a really good reality TV show.”
If current trends continue, the wolf population at Isle Royale is unlikely to survive long-term without newcomers. That’s led to an ongoing discussion about whether the National Park Service should intervene to bring in more wolves.
Brian Kaufman, a photographer at the Detroit Free Press, studied the question in his film “Predator/Prey,” which screened Saturday at Michigan Technological University as part of the 41 North Film Festival. Kaufman moderated the discussion with wolf-moose Peterson, a research professor at Michigan Technological University, and John Vucetich, an associate professor of wildlife ecology at Tech.
Screening with the film was director George Desort’s short film “Counting Wolves,” which followed Peterson, Vucetich and pilot Don Glaser during one winter’s wolf-moose count.
Since 1958, researchers have studied the relationship at Isle Royale between wolf and moose, their top prey. Absent a healthy wolf population, the moose population has risen to 1,300. That population is expected to double in four to five years, putting it at the highest it has been in the study’s history.
Left unchecked, the herbivores have a detrimental effect on the landscape, tearing up bark and depleting plant populations, particularly aquatic ones.
The NPS is conducting a study on whether to introduce wolves from the mainland to replenish the population. A final decision is expected in late 2017.
Vucetich said a wolf would have to immigrate to the island about once every 20 years to maintain genetic diversity.
Peterson said wolves should come from as close to Isle Royale as possible, and be screened for health issues such as parasites. Introducing wolves would have to be done again in 20 or 30 years.
“This isn’t a one-time-only fix,” he said.
Wolves have made their way to Isle Royale from the main land via an ice bridge from Lake Superior.
Back in the 1950s, there were ice bridges in eight of 10 years; even then, wolves only crossed over once a decade. Since 1997, there have only been three, including two in 2014-15. Two wolves made it to the island in 2015, Peterson said, although they left after spending five days there.
Vucetich has been asked if supplementing the wolf population would taint the study. But he said that misunderstands what is special about the study.
“What’s very rare, ecologically, is to have a top predator and a moose in a forest where none of them are exploited by people, where there’s no hunting, no persecution, logging,” he said. “To be able to study that ecology, that’s the really distinctive part.”