Around 1972-74ish while family camping in and around the Banff, Jasper, Mount Robson area many of the Park Rangers had Bouviers des Flandres dogs that they used to deter bears. I saw them in action a few times chasing bears out of camping areas. If the bear ended up in a tree they would just back off the dog or dogs allowing the bear enough time and space to eventually climb down and leave. To us kids the Bouvier dog was like a giant super hero dog, brave and strong enough to chase bears away and yet they were such gentle and sweet dogs that loved to get petted and hugged by all the kids. I wonder if the Bouvier is still used for bear deterrence anywhere today?