In light of all the bear defense threads popping up thought I would throw this out there.
We bought a Karilian bear dog two years ago for bear protection around our fishing lodge. We thought she would just let us know if one was around since it is so bushy here. She has done that and much more. Her eyes, nose and hearing are better than any animal I have ever seen. If something is there she will let you know every time.
In her short life she has already run off a grizzly (last year) and yesterday a sow black with cubs. What she does is goes after the bear and of course the bear will run a short distance then stop to fight. She is so fast she just circles barking nonstop until the bear moves away again. The neat part is she wont chase the bear into the next county... when she has the bear out of "her" area (maybe 300 yards from camp) she returns.
With the grizzly last year I followed with a rifle and watched, it was pretty impressive! He was an older bear and one that might have caused us trouble but she just pestered him until he left. It was neat to see how easily she could escape him.
She goes with us everywhere and the odds of surprising a bear with her along is almost 0. I have had the most trouble with bears when I have surprised them (that means the wind was in my face) that doesnt happen with her.... if anything is upwind of you she will let you know it.
I know these dogs are not the answer for everyone but for those who can have one they are the best bear protection money can buy. Plus they are nice dogs! we got ours from Dale/Sandra Drinkall of Folding Mt kennels if interested go to thier website for a lot of info on these dogs.