How are hounds trained to key in only on bears?
One of the most effective and common ways of training young dogs is to train them with experienced dogs with proven histories of not running non-target animals. Most dogs have a natural tendency to follow other dogs at least for a little while. The more bear chases a young dog is involved in, the greater the probability it will not stray to non-targets. Any time a dog exhibits a tendency toward a non-target (e.g. barks while riding in the back of a truck at a non-target such as a moose, deer, or coyote), an experienced handler will take corrective measures to stop the behavior and will continued corrective measures until the behavior is stopped.