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Reference Desk June 2012

Study Reveals Cougars Are Making a Comeback

    Findings raise questions about how humans might live in closer proximity to the big cats.

    CARBONDALE, Illinois, June 14, 2012—Cougars, those wily, storied creatures that once moved like ghosts through their far-ranging North American habitat, are making a comeback. And a researcher at Southern Illinois University (SIU) Carbondale—along with a former student—is among those spotting the trend.

    Clay Nielsen, assistant professor with the Cooperative Wildlife Research Laboratory, Department of Forestry and the Center for Ecology at SIU Carbondale, said the cougar presence clearly is increasing in midwestern North America. Nielsen worked with Michelle LaRue, a former graduate student at SIU Carbondale, now at the University of Minnesota. 

    The scientists see the trend reversing 100 years of species decline due to loss of habitat and other factors. Nielsen said the findings also raise new questions about how humans might live in closer proximity to the big cats.

    Nielsen served as principal investigator on the study (Cougars are recolonizing the midwest: analysis of cougar confirmations during 1990–2008), scheduled for publication June 14 in the Journal of Wildlife Management.

    As principal investigator, Nielsen helped with data collection, analysis and writing the paper, which used confirmed cougar sightings, carcasses, tracks, photos, video, and DNA evidence collected from 1990 to 2008 in 14 states and provinces throughout midwestern North America.

    "Cougars were driven from much of the midwest by around 1900, and their absence left a hole in the ecosystem," Nielsen said. "Cougars would be top carnivores in midwestern ecosystems, affecting prey species populations. The white-tailed deer would be the primary prey item.”

    During the last two decades, however, hard evidence of the cougar’s return has been emerging. The researchers set out to qualify and quantify that evidence, which they hoped would identify population trends and movement among the cougar—also known as a puma or a mountain lion—ranks. 

    The researchers divided the study area into an east and west region, calculated the number and types of confirmed sightings, and assessed trends brought forth by the data.  In all, they identified 178 instances of a confirmed cougar presence, with that number increasing. 

    The confirmations ranged from just one in Kansas, Michigan, and Ontario to a high of 67 in Nebraska. The cougar remains reclusive, however, with almost 80% of the confirmations occurring within about 30 miles of highly suitable forests with steep terrain and low road and human densities. 

    The most frequent means of confirming the predator’s presence was by finding a carcass, and 76% of those found were males. The researchers believe sub-adult males are leading the repopulation trend by dispersing in search of territory and mates. 

    Nielsen said the most recent findings have important implications for future management strategies for the big cat, which typically weighs 100 to 150 pounds but can grow up to 200 pounds.

    “This paper provides the strongest quantitative information to date regarding potential recolonization of cougars in the midwest, and these findings indicate that the public and wildlife managers may need to deal with increasing cougar populations in the near future if recolonization continues,” Nielsen said. “Much of the midwest has lived without large carnivores such as cougars for more than 100 years. How will we all get along...or will we?”

    Published for the Wildlife Society, he Journal of Wildlife Management publishes original research manuscripts contributing to basic wildlife science in areas such as wildlife habitat use, reproduction, genetics, demographics, viability, predator-prey relationships and others.

    Source: Southern Illinois University Carbondale


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