The dog does not do the killing if it needs to be done. The dog locates, bays, forces a bolt, and prevents the animal from digging away.
In this house, fox are always released, and most other animals are too. In those cases where the farmer wants a groundhog gone, dispatch is done quickly with a blow to the head. In this the blow came from a 5-pound digging bar. A hard blow to the head is immediate death, and there is no chance of accidentally shooting a dog.