...UMN study says
In
this photo provided by the Wisconsin Department of Natural Resources is
a confirmed cougar sighting in Lincoln County, Wis. A DNR spokesman
says an absentee landowner shared a photo captured on his trail camera
on July 30, 2014, that was discovered during a visit to the site over
the Oct. 4-5 weekend. Experts say cougars had virtually disappeared in
Wisconsin in 1910. (AP Photo/Wisconsin Department of Natural Resources)
A new study coauthored by a University of Minnesota professor shows that while Minnesota and Wisconsin both have suitable habitats for cougar populations, the big cats are likely to have only very small, if any, breeding numbers in the two states over the next 25 years.
The animals -- also called mountain lions and pumas -- seek out rugged, forested areas that are far from humans, and parts of northeastern Minnesota and northern Wisconsin fit the bill.
But cougars must travel a long way to reach those two areas, making breeding there not as likely as in some more southern states, said Michelle LaRue, coauthor of the study and a research associate in the U's College of Science and Engineering Department of Earth Sciences.
"In Minnesota and Wisconsin, if a female shows up (in the suitable habitat), it will probably be just one in the next 25 years," LaRue said, adding that, of course, a male will have to show up at the same time for a breeding population to get its start.
Dan Stark, large-carnivore specialist with the Minnesota Department of Natural Resources, agreed that a breeding population of cougars is unlikely here.
Since 2007, there have been 24 confirmed cougar sightings in Minnesota, some of which are believed to be multiple reports of the same animal. All the cougars where gender has been confirmed have been males, and Stark said the DNR has yet to confirm a wild female cougar in the state.
No reports of cougars have been confirmed in Minnesota since 2013, and Stark said it's not clear why. There have been reports of the animal being captured on trail cameras this fall, but they have not yet been confirmed.
Minnesota was historically part of the cougar's range, which extended from the Pacific to Atlantic oceans, but the arrival of European settlers and heavy hunting pushed the animals into the rugged terrain of the western states.
In recent decades, however, cougars have rebounded because of changes in management policies and an increased population of deer -- the animal's primary prey. With their range expanding, the Midwest is most likely the next stop for cougar recolonization, LaRue said.
The study she coauthored with Southern Illinois University forestry professor Clayton Nielsen focused on where in the Midwest that's most likely to happen in the next quarter-century. With breeding populations already established in Nebraska and the Dakotas, the cougar could further expand into southern Missouri, eastern Oklahoma and northern and western Arkansas, the study found.
Those places are more likely than Minnesota or Wisconsin because of how the animals travel. Cougars expand their range by what is called "stepping stone dispersal" -- stopping at one patch of suitable habitat before jumping to another, LaRue said.
Because of the proximity of suitable habitat patches extending to cougar-populated Texas and Colorado, it's easier for the animals to travel to the southern Midwest than to Minnesota and Wisconsin.
To get to Minnesota and Wisconsin, the animals would likely be traveling from the western Dakotas, LaRue said.
"There's a pretty big gap between habitat patches," she said. "Females don't travel very far, and they're going to have to travel across that expanse."
Any cougars traveling to northern Minnesota or northern Wisconsin could also be moving into areas occupied by wolves. Minnesota is home to most of the gray wolves in the lower 48 states, with a 2014-15 midwinter estimate of 2,221.
It's unknown if or how the two species would interact, LaRue said.
She say it's also unclear how human attitudes toward cougars could affect their expansion in the Midwest.
"That's a very important question, and I think that's probably the next step of research," said LaRue, who also serves as executive director for the Cougar Network, a nonprofit that researches cougar range expansion.
She said her study can serve as a proactive management tool that can help people prepare for the possibility of cougars becoming established in their states.
"If we can highlight some of these areas where the animals are likely to show up," she said, "we then can target education and outreach so people are accurately informed about the recolonization of this large predator."
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