Michigan
Department of Natural Resources Wildlife Division officials said today the state’s
wolf population has remained relatively stable over the past four wolf surveys,
the most recent of which occurred this past winter.
DNR
wildlife biologists estimate there was a minimum of 662 wolves found among 139
packs across the Upper Peninsula this past winter. The 2016 minimum population
estimate was 618 wolves.
“Based on
our latest minimum population estimate, it is clear wolf numbers in Michigan
remain viable and robust,” said Russ Mason, chief of the DNR’s wildlife
division. “A similar trend is apparent in Wisconsin and Minnesota. The western
Great Lakes states’ wolf population is thriving and has recovered.”
Fifteen
more wolf packs were found during this past winter’s survey than in 2016, but
pack size has decreased slightly and now averages less than five wolves.
The
survey was conducted from December through April, before wolves had produced
pups, and when the population is at its lowest point in the annual cycle.
“As the
wolf population in the Upper Peninsula has grown and spread out across the
region, packs are situated closer together,” said Dean Beyer, a DNR wildlife
research biologist who organizes the sampling and generates the wolf population
estimate for the biannual survey. “This makes it harder to determine which pack
made the tracks that were observed in adjacent areas.
“Movement
information we collect from GPS-collared wolves helps us interpret the track
count results, because these data allow us to identify territorial boundaries. The
minimum population estimate we generate is a conservative estimate, which takes
these factors into account.”
The wolf
survey is completed by DNR Wildlife Division and U.S. Department of Agriculture
Wildlife Services staff who search specific survey areas for wolf tracks and
other signs of wolf activity, such as territorial marking or indications of
breeding.
In
2017-2018, approximately 63 percent of the Upper Peninsula was surveyed.
After
wolves returned naturally to the U.P. through migration from Minnesota,
Wisconsin and Ontario in the 1980s, the population rebounded remarkably over
time. The pronounced long-term increase in wolf abundance is evident, despite
human cause-specific mortality, such as poaching.
However,
over the past few years, Michigan’s minimum estimate has hovered between 600
and 700 wolves, which could be indicative of a stabilizing population.
“Research
suggests prey availability and the geographical area of the U.P. are the key
limiting factors of wolf population expansion,” said Kevin Swanson, a wildlife
management specialist with the DNR’s Bear and Wolf Program in Marquette. “This
is proving to be true.”
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.
Wolves in
Michigan remain a federally-protected species which may only be killed legally
in defense of human life.
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