Yes, they do. I'm never confident that I won't be spotted until I get to over 25 feet. Seems almost like an invisible barrier to them above that point. I try to get 30 if I can and I don't recall ever being spotted up there. Tough to get that high in a lot of trees though.
In case anyone wonders, yes, that a measured height. I have a 25ft gear rope so I know where 25ft is.
