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.)
Create a Plan: A behaviourist or trainer can help you figure out the best approach for managing your dog's aggression. Make sure you only use positive reinforcement to teach your dog new behaviours.
For example, if your dog is aggressive toward strangers (lunging towards them), start off by standing far away from someone your dog doesn't know. You should be far enough away so that your dog doesn't start to growl or lunge. Then, reward with treats and praise as you gradually decrease the distance between your dog and the stranger, continuing to use positive reinforcement.
With time and consistency, your dog will begin to learn that strangers equal treats and you'll see a reduction in its aggression. This same procedure can work for getting your dog used to a variety of other situations.
Avoid Punishment: Punishing your dog for aggressive behaviour will backfire and can escalate the aggression. If you show aggression towards aggression, you will either become a challenge or you will have the dog submitting in fear. This will only damage your bond with your dog and neither will reduce aggression. For example, if you respond to a growling dog by hitting, yelling or using some other aversive method, the dog may feel the need to defend itself by biting you.
Punishment may also lead to your dog biting someone else without warning. Your dog has learnt that you will punish it for the behaviour but because you are the one who punishes, this does not apply to others. For example, a dog that growls at children is letting you know that he is uncomfortable around them. If you punish a dog for growling, he may not warn you the next time he gets uncomfortable. He may skip the warning signals to avoid punishment and go straight to a bite.
Medication: In some situations, training and behavioural modification is not enough. Dogs, like humans can be psychologically impacted by traumatic experiences. They may become aggressive because of fear. It's important to understand that a dog experiencing extreme fear, stress, or anxiety is incapable of focusing solely on the trainer or owner and thus incapable of learning new things. If this is the case, you dog may need medication to help overcome this fear. Many dogs will only need medication temporarily. Talk to your veterinarian about your options.
The Impossible Decision & Unavoidable Situations; After having done everything above and having been advised by professionals, finally, you need to consider whether your lifestyle allows you to stick with a plan.
For instance, if you have a dog that has aggression towards children, and you have children, this poses a potentially dangerous situation. In this example you have engaged a professional behaviourist and have performed all of the advice given, you’ve consulted your vet, tried the medication and are truly at the end of the road. Because you have children it is nearly impossible to avoid the situation that brings out your dog’s aggression.
In this impossible decision, the best option for the happiness of you and your dog may be finding it a new home with adults only. It is important to know that this is a very last resort and a responsible dog owner will try everything they possibly can before turning to this. They and always ensure that the new home has the ability and care to work towards mitigating the aggressive behaviour and improving the dog’s life.
Simply knowing that aggression is never an unfounded reaction by a dog is a huge step in the correct direction. It allows us to investigate and find the root cause for the behaviour and gives an avenue to modify the behaviour as well as to build a stronger and happier bond between owner and dog. There is always something that can be done to help a dog feel more at ease and improve the aggressive behaviour. Even with the ‘Impossible Decision’, it is a last resort to re-home the dog to a situation where help can be given. As humans, we have a responsibility to ensure we do not euthanise healthy dogs with behavioural issues that can be worked on ethically and successfully.