Michigan wolf population maintains
by Michigan DNR
May 10, 2016
Michigan Department of Natural Resources wildlife division officials said the size of the state’s wolf population has not changed significantly since the last survey was conducted in 2014.
DNR wildlife researchers estimate there was a minimum of 618 wolves in the Upper Peninsula this winter. The 2014 minimum population estimate was 636 wolves.
"The confidence intervals of the 2014 and 2016 estimates overlap, thus we can’t say with statistical confidence that the population decreased", said Kevin Swanson, wildlife management specialist with the DNR’s Bear and Wolf Program in Marquette.
Confidence intervals are a range of values that describe the uncertainty surrounding an estimate.
Swanson said, based on the 2016 minimum population estimate, it is clear that wolf numbers in Michigan are viable, stable and have experienced no significant change since 2014.
"Currently, deer numbers in the U.P. are at lows not seen in decades and we wondered if there would be a decline in wolf numbers as a result of this reduction in their primary source of prey," Swanson said. "We also did not observe a significant difference in the number and average size of wolf packs as compared to 2014."
This latest minimum wolf population estimate was compiled recently after surveys were conducted over the past few months, beginning in December. The wolf survey is completed by DNR wildlife division and U.S. Department of Agriculture Wildlife Services staff who search specific units for wolf tracks and other signs of wolf activity.
"While the survey is primarily a track survey, when available, we also use aerial counts of packs that contain radio-collared animals. In addition, the movement information we collect from the radio-collared wolves helps us interpret the track count results," said Dean Beyer, a DNR wildlife researcher in Marquette. "Taken together, these methods allow us to estimate the minimum size of the wolf population. In 2016, approximately 63 percent of the Upper Peninsula was surveyed."
After wolves returned naturally to the U.P. in the 1980s, through migration from Minnesota, Wisconsin and Ontario, the population rebounded remarkably until recent years when growth began to level off.
Over the past few years, Michigan's minimum population estimate has hovered between 600 and 700 wolves.
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 recovery goal of a minimum sustainable population of 200 wolves for five consecutive years was achieved in 2004." Clearly, the Michigan wolf population has maintained levels surpassing these state and federal recovery goals for more than a decade," said Russ Mason, DNR wildlife division chief.
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.
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 2008 plan, which the Department updated in 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 an endangered species in Michigan and Wisconsin and threatened in Minnesota.
Because of the federal endangered species status, Michigan citizens may only legally kill a wolf 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. The court has not yet released a timeline of its deliberations.
Legislative efforts in the U.S. Congress have also been underway to try to again delist wolves in the Great Lakes Region.
"We have limited management options available to us at this time," Mason said. "We sincerely hope that our ongoing appeal or current Congressional efforts will be successful in removing wolves from federal protection."
Swanson said, "If federal protections are removed, Michigan and other involved states would have the ability to manage wolves in a sustainable manner, by utilizing sound scientific principles as we currently employ with other valuable game species, such as bear and bobcat."
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