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Aggressive Behaviour


Canine aggression is possibly one of the most misunderstood aspects of dogs in general. With that I will start off by correcting one of the biggest misconceptions - dogs never attack for no reason. It is not in a dog’s nature to be needlessly violent; that is a trait reserved for humans. Dogs have a drive to survive and attacking a human without cause is not a good method of staying unharmed.

With that said, if your dog regularly growls, snaps, or bites, you have a serious behaviour problem on your hands. Aggression is one of the top reasons dog owners seek the help of a professional dog trainer or animal behaviourist. It is also one of the top reasons that dogs are given up or even euthanised by their owners. And we’re not just talking about large dogs and supposedly "dangerous breeds" that are prone to aggression; any breed is capable of becoming aggressive under the circumstances that create this behaviour.

Although aggression cannot be cured overnight, there are things we should consider and steps we can take to mitigate the aggressive behaviour and help your dog remain calm.

Why Do Dogs Behave Aggressively?

Personally I don’t like using the term aggressive when referring to a dog. I feel it gives those who don’t understand the term, a very negative view point of the animal in question. However, aggression is exactly what it is.

Aggressive behaviour in dogs refers to any behaviour connected with an attack or an impending attack. This includes becoming still and rigid, growling, snarling, baring teeth, lunging, and nipping or biting. (With this in mind, you must be able to differentiate between rough play and genuine aggression.)

Your first step toward mitigating this behaviour is to figure out what is causing your dog's aggression. For example, some dogs growl as someone approaches them while they're eating or chewing a bone. Others react aggressively towards a certain stature or look of a child or stranger.

Aggression isn’t limited toward people either. Some dogs become aggressive around other animals, or only specific animals, even toward inanimate objects, such as wheels, tools or certain items of clothing.

What you must keep in mind is that until you find the cause of your dog’s aggression, you cannot come up with a plan to rectify it.

Common Types of Dog Aggression

Territorial Aggression: The dog feels they are defending its space or your home from what it deems to be an intruder.

Protective Aggression: Protecting members of its pack against another animal or a person. Mother dogs have the potential to be extremely protective of their puppies and may become hostile toward anyone who goes near them.

Possessive Aggression: Protecting food, chew toys, bones, or another object the dog deems of value. (Otherwise known as resource guarding.)

Fear Aggression: The dog is fearful and tries to retreat in what they assume to be a scary situation. If cornered in this situation the dog may attack in desperation.

Defensive Aggression: The dog attacks in defence of something rather than trying to retreat first. These dogs have generally given other, more subtle, indications that they want to be left alone before biting, such as turning their head away. (See the article on calming signals to find out more about that.)

Social Aggression: Reaction to other dogs in social situations. Dogs that are not socialised properly with other dogs and people may also exhibit aggression. This can be due to anxiety and confusion with the situation.

Redirected Aggression: The dog might become aggressive toward a person who attempts to break up a dog fight. It may also happen when the dog can't reach the target of its hostility, such as a neighbouring dog on the other side of a fence. When dogs bite or nip their owners this is one of the likely reasons.

Frustration-elicited Aggression: When restricted (caged, penned up, behind a gate or on a leash), or when the dog becomes stimulated and cannot act on that stimulation, it may act out. Sometimes a dog may become overly excited, such as before a walk, and hence, nip its handler.

Pain-elicited Aggression: When injured, in pain or unwell, even a normally calm dog may act in an aggressive manner. (In this case a trip to the vet is a requirement.)

Sex-related Aggression: Two male dogs or two female dogs become aggressive when competing for the attention of a mate. (This can be avoided by spaying and neutering dogs.)

Predatory Aggression: The dog behaves aggressively with little warning when exhibiting predatory behaviour, such as when chasing wildlife. This instinct may become a serious danger when a child is playing chase with the dog. It may start out as an innocent game, but dogs with predatory aggression may quickly turn on and possibly bite the child. It can also lead to dogs attacking dangerous wild life such as snakes.

How To Mitigate Aggression

The first thing you must do is pay attention to when your dog becomes aggressive, and the circumstances surrounding the behaviour. This is paramount in determining what you can then do about it. The behaviour is just a symptom of an underlying problem. There are a number of ways you can manage the hostility and help your dog remain calm. It will take time, consistency, and possibly the help of a professional.

See Your Veterinarian: Dogs that aren't normally aggressive but suddenly develop aggressive behaviour might have an underlying medical problem. Health problems that may cause aggression include hypothyroidism, painful injuries, and neurological problems such as encephalitis, epilepsy, and brain tumours. However, anything that is causing discomfort can potentially manifest aggression.

Explain the situation in full to your veterinarian to determine whether this is the case with your dog. Treatment or medication may make big improvements in your dog's behaviour.

Call in a Professional: If you have been to the vet and medical issues have been ruled out, it's time to call in a professional dog trainer or animal behaviourist. Aggression is a serious problem. Attempting to fix it on your own may result in you, your dog or someone else getting hurt. A professional should know how to handle the situation and will help you figure out what's causing your dog's aggression as well as how to manage it. (Do ensure you hire a professional that can handle aggression.)