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, the results of which are scheduled for online publication today (June 14) in the “The Journal of Wildlife Management.” The article, titled “Cougars Are Recolonizing the Midwest: Analysis of Cougar Conﬁrmations During 1990–2008,” can be found at http://doi.wiley.com/10.1002/jwmg.396 .
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.LaRue, who was Nielsen’s master’s student from 2005 to 2007 and currently is pursuing her doctoral degree in Minnesota, served as senior author on the study. Personnel from the Cougar Network and the Colorado Division of Parks & Wildlife also were involved with the study.
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,” Nielsen said.
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 percent 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 percent 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 and LaRue previously teamed up on another study concerning cougar populations, back when LaRue was a student at SIU Carbondale. That study, which looked at potential cougar habitat in nine Midwest states west of the Mississippi River, also pointed toward the cougar reclaiming its old turf. Nielsen and LaRue found that Arkansas, Missouri and Minnesota have substantial areas that could attract and support cougars. About 19 percent of Arkansas, for instance, is highly suitable, with 16 percent of Missouri and 11 percent of Minnesota.
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, The 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.
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