Aggressive dog behavior in livestock guardian dogs sometimes becomes an issue for new and even been-around-awhile owners. So take heart - you're not alone in dealing with dog issues.
Aggressive Dog Behavior with Other Dogs
Some livestock guardian dogs are quite aggressive with any dogs who approach their stock but in particular to dogs they don't know. This is the job we have asked them to do after all.
If you use herding dogs take a bit of time to properly introduce the herding dog to the guardian to avoid confrontations later on. While the guardian dog and the herding dog should not be play buddies they can become familiar with each other through a few introductions. Livestock guardian dogs are very smart creatures and when the herding dog shows up with the producer the guardian dog adjusts and leaves it alone.
Aggressive Dog Behavior to People
People that are unknown to the livestock guardian dog may be threatened - usually by a bark or sometimes a silent visit to check them out. This is the nature of these breeds and why they are selected for the job. It is rare that these dogs will act overtly aggressive to people though. A warning is usually all it takes.
With dogs that are seriously aggressive to people the rancher will have to weigh the benefits and risks of keeping such a dog.
Dog is Aggressive With the Lambs
This aggressive dog behavior is often a matter of maturity and not really aggression. Adolescent dogs, even those raised with the sheep, often go through a phase of playing rough with the lambs. While the dog certainly knows that lambs are not dogs, this does not stop them from attempting to play or bully them as they would with other dogs during this adolescent phase.
Appropriate corrections are needed to stop this habit early and a watchful eye is warranted to be sure you don't have a class A bully and lamb marauder on your hands. Alternatively a dog that is too young or too rough may need to be removed when the lambs are young and returned later.
Dog is Aggressive With the Ewes
As dogs and sheep grow up together they will pass through various stages of comfort level with each other. A good set up during the puppy raising will prevent much of this behavior.
Each individual must gauge what they feel is happening between dogs and ewes. We notice there is a phase where ewes and dogs work their hierarchy out themselves without doing harm to one another. After that the dog and ewes respect one another and the dog ends up submitting to the ewes in various situations on his/her own.
As an adolescent, the dog may pick on ewes, singling specific ones out to chase or harass and sometimes biting. If the shepherd catches this behavior in action he should correct it. A dangle object may be attached to the dog collar. The object will interfer with the dogs attempt to run hard, pounce and otherwise play rough.
Occasionally a dog may prove to be too exuberant with the ewes and if his behavior is not curbed with age and/or correction then it may be the case that he is not suited to the job.
Livestock guardian dogs who are causing damage to ewes are displaying unwarranted and unusual aggressive dog behavior and need appropriate action immediately to ensure this does not become a habit. Removal from the flock may be necessary.
Bear in mind that when you witness exuberant or rough housing from the dog boredom may be the real issue. These dogs are social animals so if you are raising a single dog boredom can become a problem. When the dog is young it requires regular exercise and something to relieve its need to play. You may walk the dog around the perimeter once or twice a day, using the opportunity to teach leash manners. Do not take the dog for exercise outside of the stock area. Provide large balls or other dog safe toys to help relieve the boredom.