A cattle dog usually refers to the blue heeler, red heeler and Queensland heeler. It has been specially bred for Australian conditions, for rounding up cattle and helping with mustering. Because it is bred to be a "heeler", it nips at the feet of the cattle to round them up, and so a cattle dog, or blue heeler, that is a family dog often develops the tendency to nip at people's feet to try to round up its "pack". It is not an ideal family dog unless there is both a large backyard and opportunity for it to get plenty of exercise. The blue heeler quickly becomes bored, as it is bred to work.