If you have a dog that constantly charges at your fence when people or dogs go by, you know what barrier frustration or aggression is. It occurs most commonly in the herding/working/sight hound breeds, but other breeds can exhibit this behavior as well.
The dog may think that it needs to warn an intruder off, and is reinforced for this behavior when the person walking by does continue on their way. The dog may perceive that he is responsible for the human leaving the area, but has no idea that the person was leaving anyway. Often, the person outside the fence feels safe enough – after all, there’s a fence between the dog and the person, right? However, we know that children often use that feeling of safety to taunt the dog, which just serves to heighten its arousal.
While most dogs are simply frustrated, barrier frustration can be very dangerous, especially in under- or un-socialized dogs. Some dogs, once the barrier is removed, will wag their tails and assume their normal sweet demeanor. Others, however, will not hesitate to go after the intruder/tormentor/prey that they have been charging at once the gate opens or their tie-out breaks. When that happens, lawsuits and emergency room visits are possible consequences.
Since barrier aggressive dogs get better as they “practice”, it is important to consider reducing the dog’s capability to do so as part of any training & behavior modification protocol. Solid fencing and visual barriers are mainstays of early training efforts. We don’t recommend that any barrier aggressive or barrier frustrated dog be chained in the front yard, or be contained with “invisible fence”, for example, just for the convenience of the owner – that convenience won’t matter when a lawsuit is filed because Fido finally broke the chain or ran through the shock fence and bit the jogger on the back of the thigh.
For dogs that are kenneled or fenced, and where solid fencing is not an option due to expense, there’s a technique that is being successfully used in some shelters which involves installing a small canvas barrier just at dogs’ eye level to block their view: http://www.deesdogs.com/documents/reducingbarrieraggression.pdf
If you have a dog that must ride in vehicles frequently, the dog can be acclimated to wearing a “calming cap”. While not effective for all dogs, it works with many. http://www.premierpet.com/View.aspx?page=dogs/products/behavior/other
The cap is made of fabric that reduces visual stimuli at a distance, but allows the dog to see enough to navigate. Acclimation training is the same as for muzzles or head collars.
This is a handy reference for acclimation: www.premierpet.com/App_Content/media/calmCap/CalmingCapInstruction0506.pdf
For any and all unwanted behavior, think about instituting some simple principles into the barrier aggressive dog’s daily life: http://www.wagntrain.com/JustTryIt.htm. Enrich the dog’s normal environment with interactive toys and with training, and stop letting him just get frustrated watching the world go by. Except while you are specifically working on behavior modification, block his access to the visual stimuli that set him off. Remember, it’s harder for him to unlearn behavior than to learn it in the first place, so give him some help by reducing the necessity for him to perform the unwanted behavior.
Many barrier aggressive dogs are anxious, not truly aggressive (is your dog OK with no barrier present?). In addition to what has been mentioned already, you can think about using a DAP diffuser (dog appeasing pheromone), Sniffers 101 dog treats (contain calming herbals and are soft and can be broken up into tiny pieces for regular training), an anxiety wrap or thunder shirt (or a tight tee shirt cut to fit the dog). Read “The Cautious Canine” for some additional ideas on general work with anxious dogs.
If you believe that your dog is truly aggressive and would bite if the barrier were removed, get help from a qualified behaviorist. The American College of Veterinary Behaviorists has an online search function on their site: http://www.veterinarybehaviorists.org/