Cougar sightings are controversial these days. Lots of people spot cougars, or think they do. Wildlife officials are often skeptical. This article does a great job explaining how that skepticism comes about. Coincidentally, it also cites a certain naturalist author with cougar experience.
Experts weigh in on cougar sighting | Denton Record Chronicle | News for Denton County, Texas | Local News
Meanwhile, in Alabama, a man survived an attack by a cougar (which in that part of the country is often called a panther).