They are trained pets. These will deliberately annoy the coyote by chasing then retreating. Just like the coyote can bait the dog out, the dog can bait the coyote in. Any dog works to an extent. It helps to have a couple of dogs or one that minds so it don't get to far away and get chewed up. This time of year while the coyotes are denning it is even better since they are territorial. I usually call them, but once they see the dog or the dogs see them, the game is on. My female will go into hunting mode as soon as she hears a coyote, even if it is a mile away. Justin