When Tony Rondeau found a narrow band of forest that separates a field and a lake on private land he had permission to hunt, he set up a deer stand, figuring it would be a natural corridor for whitetails. Then he attached a trail camera to a tree, hoping to capture an image of his quarry. Instead, Rondeau's camera snapped a photo of another hunter, albeit one with four feet and a long tail—a hunter some people call the ghost cat.

Several days later, Rondeau, who lives in Fergus Falls, decided to go bowhunting. He brought a young hunter with him.

"I said, 'Let's check the camera first.' Which I did. Then I said to her, 'You're not going to believe this, but there was a mountain lion here,'" Rondeau said.

According to the camera's time stamp, the mountain lion, or cougar, walked within 15 yards of Rondeau's stand in Otter Tail County at 7:25 p.m. on Oct. 1, 2011. Rondeau hadn't seen the big cat before, and he hasn't seen it since. He contacted Don Schultz, the DNR area wildlife manager in Fergus Falls, and the two of them went back to the area and searched in vain for feces, hair, or tracks. Still, Schultz considered it a verified cougar observation because of the trail camera image.

Reports of people claiming to have seen cougars in Minnesota are relatively common, but the number of verified observations is far lower—19 from 2010 through 2014. DNR biologists are responsible for verification via a clear photo, DNA, a dead animal, or unmistakable tracks. Even then, confirmations could be identifying the same cougar in different places.

At this point, DNR wildlife biologists have found no evidence of a breeding cougar population in Minnesota. The documented cougars mostly fit the pattern of young males dispersing from established populations in areas such as the Black Hills of South Dakota. Thanks to DNA testing of road-killed cougars and tracking of radio-collared individuals, it's clear to biologists that some animals have struck out in search of a new home, but it's anyone's guess whether Minnesota will someday be home to a breeding population.

"That's the million-dollar question," says John Erb, a DNR wildlife research scientist in Grand Rapids.

Before European settlement, cougars ranged throughout much of the nation, including Minnesota. They were the widest-ranging land mammal other than humans. But by the early 1900s, cougars had been extirpated from most of their range in the East and Midwest due in large part to bounties paid by federal and state governments, according to Michelle LaRue, a research associate at the University of Minnesota and executive director of the Cougar Network. The network is a nonprofit research group that studies the role of cougars in ecosystems and maintains a database of confirmed cougar sightings.

Minnesota never paid a bounty for cougars, but many Western states used the bounty system in an attempt to protect cattle and other livestock, from the 1800s into the mid-1900s. Despite bounty hunters and landowners killing tens of thousands of cougars in states such as Oregon, Montana, and Utah, some cougars held on in the West, where they hid among the rugged terrain. In the 1960s and 1970s, states that had offered bounties shifted management strategies and began treating cougars as a game species. With the help of such protections, cougar populations rebounded throughout Western states.

By the late 1990s and early 2000s, cougars moved eastward from states such as Washington, Oregon, and Idaho and established breeding populations in the Black Hills of South Dakota, the Badlands of North Dakota, and western Nebraska. As these new populations have expanded, individual animals have begun striking out in search of new territory. Cougars have been confirmed in Minnesota and other states in the Midwest. LaRue says evidence strongly suggests cougars are recolonizing parts of their historic range. In published research, LaRue reported 178 cougar confirmations in the Midwest between 1990 and 2008. Five were in Minnesota. Of the cougars that have been confirmed in Minnesota, some are wild animals known to have dispersed from states to the west, and some were captive before escaping or being released, according to LaRue and Erb. In some instances, biologists aren't certain whether animals were wild or had spent part of their lives in captivity.

"Because cougars are territorial, males set up a territory and will kick out other males, and only tolerate a few females," says LaRue, whose master's degree research included cougar habitat and dispersal corridors. "For decades in the West, these males were dispersing into other patches of habitat in the West. Now in the West, there are fewer territories remaining, so they have to strike out even more. They have to go somewhere, and the Midwest is where they are going."

Female cougars will disperse, but the behavior is associated most strongly with males. Male cougars have home ranges of hundreds of square miles, so a cougar may have to cover great distances to stake a claim on new territory.

In early 2005 a young male cougar that was fitted with a radio collar in the Black Hills traveled through North Dakota and crossed into northwestern Minnesota. He spent time in Roseau River Wildlife Management Area before moving on.

In September 2009 a motorist hit and killed a young male cougar near Bemidji. Its DNA was genetically consistent with cougars in North Dakota.

The apparent journey of one particular cougar shows just how far they can range. In December 2009, nighttime video from a Champlin police officer's dashboard camera showed a cougar slinking through trees in a residential area. It was headed in the direction of the Mississippi River. DNR biologists soon after found cougar scat in Vadnais Heights and verified tracks in Stillwater, which showed the animal apparently was moving toward Wisconsin. During the next two months, Wisconsin biologists tracked a cougar moving through that state. Based on the animal's appearance and tracks, they believed it was the same animal that had been documented in Minnesota.

And the cougar kept moving. Biologists in Minnesota and Wisconsin had collected hair and scat for genetic testing. When a car hit a cougar in Connecticut in June 2011, genetic tests revealed the cougar was the same one that had moved through Minnesota and Wisconsin. DNA testing upon the cougar's death showed its genetic structure matched that of cougars from the Black Hills region of South Dakota.

"The journey of this mountain lion is a testament to the wonders of nature and the tenacity and adaptability of this species," said Daniel C. Esty, then-commissioner of the Connecticut Department of Energy and Environmental Protection. "This mountain lion traveled a distance of more than 1,500 miles from its original home in South Dakota—representing one of the longest movements ever recorded for a land mammal and nearly double the distance ever recorded for a dispersing mountain lion."

That cougar was the first one confirmed in Connecticut in more than 100 years.

In places with resident cougar populations, such as South Dakota, vehicles often hit animals. Only one such accident has occurred in Minnesota. This is among the reasons DNR biologists don't believe there's a breeding population in the state. But they don't discount the possibility of a breeding population becoming established in the future, in part because Minnesota has the habitat and prey to support cougars. As habitat generalists, cougars take advantage of whatever is available to them. Most suitable are large blocks of contiguous forest with dense cover and few people and roads. For food, deer top the list.

"Northern Minnesota is perfect," LaRue says. "It's the same reason wolves are there, basically." 

According to a paper LaRue wrote with Clay Nielsen, forestry professor at Southern Illinois University Carbondale, Minnesota's potential cougar habitat is among the best in the Midwest. Only Arkansas and Missouri had more "highly favorable habitat," which amounted to 19 percent and 16 percent of those states, respectively. Eleven percent of Minnesota had such habitat. Each of the two Dakotas and Nebraska has less than half the potential habitat base as Minnesota.

"Studies all conclude that northern Minnesota has a lot of potential habitat," Erb says.

There is no credible evidence that cougars are breeding in Minnesota, Erb says when pressed. But continue the line of questioning and he'll tell you of a couple of instances in which cougars have behaved in ways consistent with individuals trying to establish a territory.

One year, a cougar was confirmed in the northeastern part of the state. A year later, in almost the same spot, there was another confirmation. There's no way to know if it was the same animal.

In 2013 a cougar was confirmed in western Minnesota's Douglas County. That cat, which had been treed by coyote hunters, stuck around the area for at least a month. Around that time, people reported seeing a cougar a few miles away. It could have been the same animal, Erb says.

"Over a one- to three-month period, we had a cat in 2013 that seemed to be staying put in spite of being harassed, you could say, by people," he says. "Was it trying to establish a territory?" If it was, indications are it did not succeed because it disappeared before long. It's unknown if the animal was killed or left of its own volition. And the cat may not have been wild. A cougar that spent part of its life in captivity may have been less likely to leave the area, even in the face of human disturbance, says Erb. On the other hand, it could have been a wild cat that found habitat and a food source it liked, Erb says, but was missing a key component: a female.

Erb's files include confirmation of about 30 cougars in the state since 1991. Of those cougars, Erb can pinpoint the sex for nine. Three of those nine were females. Based on their behaviors, he considers each of those three likely to have been captive at one time. But there's one that makes him wonder. In 2002, Bloomington police cornered a cougar in a brushy area and shot it. Its behavior seemed atypical of a wild animal, but "we can't rule out the potential it was a wild one," Erb says.

Still, the chance of cougars becoming established in the state is a "low-probability event," he says. A male and female would have to meet in one spot and then stay in the same area. They would have to breed, and their young would have to survive.

"It would take a lot of rare events for this to happen," Erb says. "But rare events happen. Sometimes, people get struck twice by lightning. If it does happen that a male and female show up at the same spot, there's not any good reason to say they couldn't establish a population."

DNR wildlife managers have spent little time formally planning for such an eventuality. But a resident population would have subtle and not-so-subtle impacts. Ungulates, including deer and moose, for example, make up about 80 percent of cougars' prey base. Results of a Canadian study published in 2010 showed individual cougars killed about one ungulate per week, which the authors said was in line with results from previous studies. Livestock producers might have to deal with increased depredation, LaRue says. There would be management questions to answer: Should they be hunted? Should there be a population goal?

And it's not clear how cougars would fit into northern Minnesota's ecosystem. "We don't know a ton about what the dynamic between wolves and cougars might be," Erb says. "They coexist in a few other places, but nowhere else is the density of wolves probably as high as we have."

And there's the human dimension. Erb figures fears would be ratcheted up as people wonder if a potentially deadly predator could be slipping silently through the woods. Yet compared with other dangers, the chances of getting attacked by a cougar are slim. Since 1890 roughly 20 people have been attacked and killed by cougars in North America. However, lightning kills an average of 49 people per year in the United States, according to the National Weather Service, and as many as 200 people die each year as a result of deer-vehicle collisions, according to Insurance Journal.

"Most people would think of these as such low risks that they don't think twice when they leave their home each day," Erb says, "yet the risks are substantially higher than being attacked or killed by a cougar. Our fears are not well aligned with actual risks, especially when it relates to large carnivores."

Even so, when Rondeau saw the cougar on his trail camera, he was surprised, but not hesitant to head back into the woods. He's been in cougar country before, having heard their piercing screams during trips to the Bighorn and Rocky mountains and the Black Hills.

"That raises the hair on the back of your neck, I can tell you that," he says. "But, no, I'm not concerned about them being around. There's wolves around, too, and I'm not worried about them either."