Yes, I'd say the 'woofers' were adult and the 'tweeters' juvenile Great
Horned Owls. I've heard the screeching call on numerous occasions from
birds I knew were young. What I don't know is if adults ever make this
call.

Dennis Paulson, Director phone 206-756-3798
Slater Museum of Natural History fax 206-756-3352
University of Puget Sound e-mail dpaulson at ups.edu
Tacoma, WA 98416