What is the cause of most aggressive behaviors?  Fear is the answer.  Most dogs are not aggressive by nature.  In fact, aggression without fear is very rare.  It’s usually the “fight or flight” response that causes the aggression.  Usually, when a dog is in an area where flight is off the table, the only other options are submission, or fight.

The root of fear aggression is not singular.  It could be genetic, inhumane treatment, or even its owner causing the problem unknowingly.  For instance, the owner may physically punish the dog for certain things and is ignorant to the repercussions of creating a fear aggressive dog.  Improper socialization is another big reason dogs choose the “fight” response.

How can I tell is a dog is fear aggressive?  First, their body postures typically give it away – they are stiff, stare without blinking, lip-lick a lot, tail is either down or wagging rapidly, and the obvious sign is growling or showing teeth with tight lips.  Actually, the most obvious signs are a lunge or a bite.  Note that a fear aggressive dog will usually snap a few times at the person or animal in an attempt to move them further away to create distance. 

How do you cure fear aggression?  I personally feel there is no 100 percent cure for this condition.  However, one can certainly curtail it drastically.  It starts with positive reinforcement, desensitization, and counter-conditioning.  Assuming the fear aggression is toward people, ask your visitors to avoid eye contact with your dog and don’t squarely face your dog either.  Also, no sudden movements, especially in the direction of the dog.  Every dog has a reactivity threshold – a distance whereby the dog becomes reactive when the threshold is crossed, and behaves on alert but not reactive on the other side of the threshold.  It’s up to you to find this threshold, which will most likely be outside at a distance, as inside does not have enough space. 

Assuming you want your visitor to come into your house, I recommend that you first meet outside to give your dog the “flight” option as well as keep him below threshold.  Planning ahead, have your visitor carry treats, which he should toss to your pup at the meeting.  Then walk your dog toward your visitor and say hello and start talking as you walk together away from your home.  It doesn’t have to be a long walk or a long conversation, but both of these things will help your dog feel more comfortable with your visitor.  After the walk, take it inside and keep your dog on leash while you and your pup are seated away from the visitor.  For the same visitor, repeat this process a few times before simply switching it to an inside greeting with the visitor always tossing treats to your pup at the beginning.  Give your dog a Kong filled with frozen, wet dog food, or a bully stick to ease his tension during your visitor’s stay.

For curtailing fear aggression over the longer term, counter-conditioning and desensitization are necessary.  The methods are very simple, but require dedication, repetition, timing, and patience.  Let’s say your friend Bill has agreed to volunteer as the “scary stimulus”.  Usually a park is the best place to work.  Have Bill stand beyond your dog’s threshold of reactivity.  At this distance, your dog should be quite aware of Bill, is concerned, but not overly. Use only high-value treats (like freeze dried beef liver).  Now, wait for your dog to look at Bill – when he does, instantly say “yes!” and deliver a small treat.  Wait for another glance toward Bill and rinse and repeat.  Do this many, many times over a period of 10 minutes or so.  After standing still for a few minutes in the next session, have Bill move parallel to you and your dog and continue to “yes!” and treat your dog each time he looks Bill’s way.  Then have Bill arc a little closer to your dog, ever so slightly, then have him stop.  If your dog remains below threshold, continue this exercise for 10 minutes.    In time, like several more sessions, you should be able to make good headway getting Bill closer and closer.  If at any point your dog starts redlining, increase the distance again for a while.

Over time,  try to enlist other friends to help you out.  You can also go to a park and stand away, beyond the threshold, from strangers and do the above counter-conditioning and desensitization.  Take it slow.  In time, you should be able to have Bill and friends walk closer to you and toss treats and walk away.  After several weeks (usually), and contingent on your dog being a relaxed, calm state, have Bill and friends linger and talk with you from a distance as they randomly toss treats to your pup.  One last thing, and to repeat, take it slow and always err on the side of caution.  Be ready to back it up or even start over if your dog is having difficulty.  Eventually, at your dog’s pace, you will reach the point where he becomes tolerant of people in close proximity.  But keep in mind that, just like people, dogs can have bad days and sometimes overly stressful days.  Be sure to take your dog’s pulse (figuratively) prior to each session.  Good luck!