On a snow-swept back road in Delta County, a Michigan Department of Natural Resources wildlife biologist drives his vehicle slowly. Watching out his windows, he scans each set of animal tracks he sees pushed into the fresh snow.
Among the footprints left by bobcats, white-tailed deer, snowshoe hare and other animals, he’s looking for the large-pawed tracks of gray wolves, laid out in a path down the road or into the woods.
Discovering wolf tracks – and then following them for long distances – helps biologists estimate population size and delineate where, and how, wolf packs are spending their time this winter.
Population dynamics
Originally native to Michigan, wolves had all but vanished from the Upper Peninsula – not including Isle Royale – by the early 1960s. This occurred through hunter bounties and as white-tailed deer populations declined.
Michigan protected wolves as endangered species in 1965. Federal protections were solidified under the Endangered Species Act of 1973.
As neighboring Wisconsin’s wolf population began to rebound during the 1970s, reports of lone wolf sightings increased in the U.P. Biologists confirmed a pair of wolves in the central U.P. in the late 1980s, a union that produced pups in 1991.
Since the winter of 1993-94, combined wolf numbers in Michigan and Wisconsin have surpassed 100, meeting federally established goals for population recovery. The Michigan goal of a minimum sustainable population of 200 wolves for five consecutive years also was achieved.
From 1994 to 2003, the U.P. wolf population saw an average annual growth rate of 19 percent. Growth shrunk to 12 percent as the wolf population neared the maximum level the U.P. could sustain – the biological carrying capacity.
Since 2011, wolf population estimates have not changed significantly. The DNR’s most recent minimum estimate of the U.P. wolf population was 636, issued in spring 2014.
A new DNR wolf survey began in December. No preliminary results are available yet, but a new minimum population estimate is expected in April.
Biologists are surveying wolf populations in some areas and extrapolating that data to estimate the number of wolves across the region.
“As we’ve done over the past few years, to reduce staff effort and expense, a stratified sampling method is being used to carry out the survey throughout the Upper Peninsula,” said Kevin Swanson, a wildlife management specialist with the DNR’s bear and wolf program. “We are now more than halfway through that survey period.”
During February, survey biologists began looking for signs of breeding exhibited by scent marking and blood in urine, which indicates a female wolf may be in estrus (heat).
“Based on the wolf sign I am finding while searching for packs in central and southern Marquette County, northern Menominee and northern Delta counties, I do not anticipate any drastic fluctuations in wolf abundance in that particular area,” Swanson said. “But results may vary significantly in other parts of the U.P.”
The migration of deer from the northern to the southern parts of the U.P. was postponed by several weeks this winter, which has been comparatively milder than the past three.
“The delayed deer migration is now over in many areas so we will focus more of our survey efforts in deer yarding complexes, places where wolves frequent to prey on deer,” Swanson said.
In the Lower Peninsula, over the past few years, there have been persistent reports of sightings, tracks and other evidence of wolves.
In March 2014, biologists with the Little Traverse Band of Odawa Indians discovered tracks and collected scat from what was presumed to be a wolf in Emmet County. DNR biologists also visited the site.
In September 2015, confirmation was received from Trent University in Peterborough, Ontario, that the Emmet County scat submitted for DNR analysis was from a male gray wolf. This marked the second confirmation of wolf presence in the Lower Peninsula since 1910. The first occurred in 2004 when a wolf collared by the DNR in Mackinac County was caught and accidentally killed by a coyote trapper in Presque Isle County.
The DNR’s ongoing wolf track surveys are conducted only in the U.P. Wolf reports in the Lower Peninsula continue to be investigated.
Legal challenges
In January 2012, citing wolf recovery in the region, the U.S. Fish and Wildlife Service took gray wolves off the federal endangered species list in Michigan and Wisconsin and the threatened species list in Minnesota.
“Gray wolves are thriving in the Great Lakes region, and their successful recovery is a testament to the hard work of the Service and our state and local partners,” Fish and Wildlife Service Director Dan Ashe said at the time. “We are confident state and tribal wildlife managers in Michigan, Minnesota and Wisconsin will effectively manage healthy wolf populations now that federal protection is no longer needed.”
The ruling allowed Michigan, Minnesota and Wisconsin to manage wolves according to their wolf management plans. Michigan’s plan was crafted with the help of a panel representing a wide span of interests ranging from Native American tribes to trappers, hunters and environmentalists.
The 1997 plan, which was updated in 2008 and 2015, allowed for lethal means to control a limited number of wolves each year where conflicts had occurred. Michigan law allowed citizens to kill wolves that were actively preying on their hunting dogs or livestock.
However, Michigan’s laws on wolf depredation and the ability of wildlife managers to use lethal means, including hunting, to control wolves was suspended in December 2014, after a ruling from the U.S. District Court in Washington, D.C.
In a lawsuit challenging the federal delisting, the court ruling found in favor of the Humane Society of the United States, ordering wolves returned to federal protection. Wolves have since remained classified as endangered species in Michigan and Wisconsin and threatened in Minnesota.
Because of the federal endangered species status, wolves may legally be killed in Michigan only in defense of human life.
After the court’s finding, Michigan, Wisconsin, some private groups and the U.S. Fish and Wildlife Service appealed the decision, filing their initial legal briefs in the case late last year.
“In over a decade of litigating about delisting the gray wolf, this is the first time the U.S. Fish and Wildlife Service has been willing to bring an appeal,” said Trevor VanDyke, director of the DNR’s Legislative and Legal Affairs Office in Lansing. Read more