I was once sleeping in a fully zipped bivy sack in the winter in Little Yosemite Valley up by half dome, food safe in a bear container far away. A black bear came to sniff my bag. After what seemed like 4 hours, but was probably only 30 seconds, he moved on and found an old film camera in my back pack and chewed on that. Sigh. Black bears in the lower 48 I'm ok with. Your real bears up north are new to me. Thanks for the insights!