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Classifying and Controlling Aggressive Dogs


One of the most common reasons dog owners seek help with professional trainers or behavior experts is their dog is being too aggressive. In this article we will look at aggressive dogs, why it happens and what you can do. Keep in mind that some breeds are naturally more aggressive than others though that does not mean you have to accept bad behavior. Some breeds have just been bred for certain traits like guarding, hunting, combat and so on, so those breeds are more predisposed to certain forms of aggression. However more key to predicting aggression in a dog is their temperament, their history and their training and socialization.

Characteristics of an Aggressive Dog

When we think about an aggressive dog we are talking about a dog who is aggressive towards other people, pets and dogs. There are a range of bad behaviors that can reflect this but typically involve the following sequence though some miss some steps or do several simultaneously;


Going still and rigid

Making a threatening guttural bark


Lunging at another person or animal but making no contact

Showing their teeth

Snarling which is when they growl and show their teeth at the same time

Doing a muzzle punch which is when they punch the other person with their nose

Mouthing to control but not applying pressure

Snapping at whatever they are being aggressive towards

Giving the person or animal a nip but leaving no mark

Biting quickly and tearing the skin

Biting hard enough to also cause bruising

Biting that leaves puncture wounds behind

Giving several bites quickly one after the other

Biting and shaking

It is rare for dogs to bite straight away without giving some kind of warning first.

What Causes Aggressive Behavior in Dogs

If you dog is being aggressive you need to know what triggers it. Think about whether there is a person in particular that bears the brunt of it, if it happens at a certain time or place, what else was going on that might have triggered it, did something just happen to your dog to cause it and what stopped him or her in the end.

In some situations it is natural for a dog to respond with aggression. It is common for puppies to be aggressive towards strangers for example and some studies suggest that as many as two thirds of dogs will bark threateningly at strangers. Some dogs may only be aggressive in certain situations like visiting the vets, the groomer or at the postman. There are sometimes ways to help avoid triggering the aggression. Meet the postman at the mailbox, groom the dog yourself, avoid having small children in the home if that is their trigger. A dog that is aggressive to other dogs is not necessarily going to be aggressive towards other people and vice versa.

There are several forms of aggression in dogs that can be classified. They are;

Protective Aggression – The dog perceives someone or something of his is being threatened.

Territorial Aggression – Someone enters his territory and he does not want them there.

Fear Aggression – He is scared of something.

Possession Aggression – Someone is taking or touching something he sees as his.

Frustrated Aggression – The dog gets frustrated over something and uses aggression to express it

Defensive Aggression – Similar to fear aggression except in this case he goes on the defense.

Pain-Elicited Aggression – Your dog is hurt and that pain causes them to react with aggression.

Social Aggression – Social situations cause him to become aggressive.

Sex-Related Aggression – The aggression is to the same gendered dogs and is related to sex.

Redirected Aggression – Similar to frustrated aggression.

Predatory Aggression – Unlike other forms of aggression there is little to no warning when this form of attack happens.

Assessing The Risk Level

In order to assess whether you can help your dog and whether it is safe to be around them there are several factors to consider.

Triggers/targets – What are the triggers and can they be mitigated? If it is something like she does not want a family member to touch her food bowl, then just stop touching it. However if it is unsafe to enter the kitchen that is different. If she is wary of strangers when walking is there a less populated route you can take? If she is likely to attack people or dogs when out again that is a problem.

Size – Big dogs are harder to control when they become aggressive and they can do more damage. Can you control them if you need to?

Severity – If they growl and show their teeth but do not go beyond that, they are going to be easier to deal with then those that bite.

Motivation – Changing aggressive behavior takes motivation from you, into motivating them. If they respond well to praise and treats you have a foundation to train them on or at least get a professional's help to do so.


Predictability – Is it easy to predict and therefore deal with an aggressive occurrence? Dogs who attack with no warning and are hard to predict are more dangerous.

History – Dogs that have bitten before are more likely to do so again.

Age – Younger dogs are more malleable and easier to train into better behavior.

Treating an Aggressive Dog

In some cases an aggressive dog is caused by a medical condition and this needs to be checked by a vet. If your own attempts at training your dog have not worked or the aggression is on the severe end you may want to consult with a behavior specialist. They will assess the dog, its environment, how you handle it, as well as anything else relevant and then come up with a training plan. They will work with you to implement it and adjust it if necessary depending on your progress. It is possible to reduce and even eliminate aggression from some dogs with enough patience and determination. However you should always take steps to ensure your dog is not putting anyone else at risk of harm as dogs who have a history of aggression can sometimes return to it.

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