Report 24732: Hunters have camper shaken and hear whoops on the North Kiabab

On Saturday 09-13-08 around 2am in the morning in the Kaibab which is located in Arizona. My husband Chris and his brother were there to do some Grouse hunting. He stated that he was a sleep when he felt our pop-up camper being pushed and would stop and repeat. He said that he stood up and walked over thinking it was his brother moving alot in his sleep. He woke his brother up to ask him he said No!  My husband goes out side to see what was going on he looked all around the camper and nothing. He said that all of a sudden he heard some thing walking in the woods behind the camper. He shined his flash light and saw nothing. He walks back in the camper when he heard this loud whooping sound it went on for a while. He has heard nothing like it before. He hunts alot,I found your web site the same recording of the whooping sound is the same sound that he heard. We are business owners,good people we have to see it to beleave it sort of people. For my husband peace of mind he wanted to contact someone  to let them know. I didn't know if I should contact game & fish.I feel more comfortable contacting you. Thank you!!