One of the traditional roles of the English Shepherd was to keep the farm free of pests and predators. Our dogs are no exception. From the time they were pups they have all shown an innate instinct to run off or kill those animals they see as a threat to their territory.
Our area is home to many wild creatures including coyote, fox, raccoon, possum and groundhogs (also known in this area as woodchucks). We also have a healthy population of deer although our dogs seem to accept their presence as long as they stay out of the pastures and garden.
Engaging in conflicts with the wild animal population is one of the risks in a farm dogs life; a risk that must be balanced by the freedom the farm dog must have to do his job.
The picture below shows the unfortunate consequence of a tangle with what we believe was a large groundhog (be forewarned; it's a little gruesome). Rudy discovered its den in our woods and in an effort to drive it out, stuck his head in. The groundhog grabbed a hold of his ear and nearly pulled it off. It was attached only at the very top and it took a good two hours and close to 30 stitches to reattach. We're very lucky that the vet could see him immediately. At first we had no idea what happened. We asked our vet what in her opinion could do this kind of damage. She said she would put her money on a ground hog. Two days later (witnessed by my son and his friend), Sawyer and our old farmcollie Judah found that groundhog's den, killed it and brought back the prize.
What's 
Farm dog retribution