Report 25704: Cougar research interrupted by wood knocks at Bell Smith Springs

I was in Pope county Illinois researching cougars. I arrived at camp on a Wednesday and happened to be the only camper in the area. It was near sundown when I arrived so I was cutting wood through out the night. I can recall breaking limbs around midnight when to my surprise I began hearing wood knocks coming from the near by canyon. These knocks were aggressive and LOUD. There was no wind either. The knocks returned on Thursday night and lasted until I fell asleep. The next day campers filled the site and the wood knocks stopped. By sunday the campers had left and I was alone again. I didn't hear the knocks that night but I remember waking up around 3 a.m. with a fear of something comming to my camp site. I got up and heard foot steps about 20 yards away so I immediatly packed up and left. I returned the following spring and documented large foot prints a couple miles away from the same camp site.