Coyotes in the study's six parks and nature preserves were already being monitored as part of the wider, long-term Cook County, Illinois, Coyote Project, which Gehrt has been conducting since 2000.
For this latest study, the researchers live-trapped free-roaming cats in or near those parks and nature preserves. They recorded each cat's age, weight, fur coloration, body condition and other traits; took blood samples for later testing; fitted the adult and juvenile cats with radio collars for tracking their movements; and released all the cats at or near their capture sites.
Findings showed that most of the sampled cats were in good body condition, with only a few mostly minor health problems. Blood tests indicated, for example, that the cats had little exposure to feline immunodeficiency virus, also called FIV or feline AIDS, and to feline leukemia virus.
Cats that had been spayed or neutered were in even better shape.
"There's definitely a need to sterilize (free-roaming cats) to control their overall population, and in some cases it may help them maintain better body condition," Gehrt said. "That's another finding of this study."
In fact, only 20 percent of the cats died during the two-year study, with vehicle strikes and predation probably by coyotes, he said the main causes.
Based on that survival rate, coyotes preying on feral cats "doesn't happen as much as people think it does," although the predation rate on indoor-outdoor pet cats may be greater, he said.
The study cats' survival rate surprised him, he added.
"I thought it would be much lo
|Contact: Stan Gehrt|
Ohio State University