Understanding Different Types of Dog Aggression: Part 2

It is possible to specify different categories of dog aggression, but it’s important to keep in mind that the underlying reason for most forms of aggression is that dogs react to any kind of real or perceived threat with fear. This fear might appear illogical or insignificant to a human mind, but it impacts a dog’s life and behaviour significantly.

In order to start working with an aggressive dog, it is crucial to view the situation or triggers which cause a dog to resort to aggression from a dog’s perspective, which requires a lot of observation and the use of intuition instead of just logical thinking.

Let’s first look at a lot of different reasons why dogs display aggressive behaviours.

Showing teeth doesn’t always mean aggression

Territorial Aggression

Stay off my home turd!

Territorial Aggression is one of the easiest understandable reasons why a dog resorts to aggression as the dog simply tries to communicate to an intruder, be it an unfamiliar human or another dog, to stay off its home or yard.

This form of aggression can be intense as the dog fears for itself and its human parents. Some dog breeds are more protective of their home turf than others and will attack or bite an intruder, when he/she comes too close to what the dog perceives as its territory.

This behaviour is deeply ingrained in the DNA of certain dog breeds who still haven’t completely forgotten their wolf ancestry. If an intruder dares to invade a wolves pack territory, the resident wolves will vigorously defend their area and attack to drive off the invader.

Guarding and protecting one’s home from outside forces has always been a valued characteristic in dogs and has been conserved and strengthened over centuries through selected breeding. Having a few aggressive dogs around to protect a remote castle from a marauding barbarian horde was definitely the right choice during medieval times, but Fluffy trying to tear the Amazon delivery guy apart, is probably a less wanted behaviour nowadays.

Protective Aggression

One for all, all for one!

For most of us humans, dogs are family and we will do all and everything to make them feel that they belong in our home. The same is true for dogs, they are a social species and for many, we are part of their pack. If they think that any member of their pack is in danger, they will immediately come to help to defend that individual. Even the tiniest pack dogs, and especially the handbag sized ones, are often overprotective when they think that one of their family members or friends is in peril.

In the human and dog world a perceived threat can be two entirely different things and it’s not always easy to understand why sweet little Daisy turns into Daisy the Terrible when her pet parents bring their newborn child into the family. While this behaviour might look initially appealing, the family dog bravely protecting the little one, problems will soon arise when Daisy starts to treat everyone outside the immediate family, including friends and relatives, as threats to the baby’s safety and attacks them when they dare to come near.

Possessive Aggression

That’s my bone!

Another form of aggression which is easily recognized is possessive aggression, when a dog guards their prized possessions from others, if there is a real need to do so or not. This might be Fluffy’s beloved Pooh Bear or the extra large chewing toy he got last Xmas; try to touch it and you will feel Fluffy’s wrath and teeth painfully your hand.

Food aggression is a typical example of possessive aggression and stems from its wild ancestors, who had to compete for food, nesting sites and mates to survive. Even our little furry friends no longer face such harsh realities in their spoiled life of comfort and luxury, many still show the tendency to guard their possessions from others, if there’s a need or not.
This form of food aggression is easily avoided by letting your dog eat alone and in peace, but what if you have another dog in the house? Expect daily brutal battles during mealtime.

There’s an old saying: „Let sleeping dogs lie“ for good reason. Some dogs guard their favourite resting spot, crates, dog beds and even their pet parents’ beds viciously.

Unlike some other forms of aggression, there are some quite good methods to help your dog to overcome possessive aggression. It will take lots of time and patience, but eventually you might even be able to take Fluffy’s food bowl underneath his nose without the risk of getting torn apart. Still, be super cautious, possessive aggression can trigger very violent responses in dogs.

Fear Aggression

I’m so scared and if you don’t back off, then I will bite!

As already mentioned in the beginning of this post, almost all forms of aggression can be traced back to some kind of fear or anxiety in your dog. Only predatory and disease related aggressions have other reasons than fear.
Fear aggression is often not recognized as they manifest usually in behaviours which are defensive and intended to increase the distance between the perceived threat and the dog, in other words, your dog is telling the other one to „f*** off and stay away!“


Overtime, especially if humans, unlike dogs, don’t understand what the dogs is trying to communicate, the behaviour is changing from defensive to offensive, as the dog learned that the less aggressive approach clearly doesn’t work with those dumb humans.

Fear- and anxiety-related aggression becomes a huge problem when your sweet little friend is sick and needs to visit the vet.
But also your vacuum cleaner could tell stories, whenever its working and Fluffy suddenly starts to attack it. Some dogs even react violently to their own reflection in a glass or mirror or any loud noise.

To help a dog to alleviate its fear aggression, a lot of slow socialising is needed, which will help them overtime to understand that other dogs, humans and vacuum cleaners don’t necessarily mean harm.

Almost any dog will turn into an aggressive one if it’s cornered or trapped— it’s just it’s natural instinct. When animals and people are afraid of something, they want to get away from it, but if escaping isn’t an option, the flight response will change instantly into a fight response. Think of yourself, if confronted with a life threatening situation, wouldn’t you fight for your life when running away isn’t possible? A dog can be afraid of a person or another animal and still attack, if it thinks that this is the only option remaining.

Never ever physically punish your dog! Not only because it will never solve any issue or help your dog, but also for your own safety. Some dogs will crouch down and retreat at the prospect of physical punishment, but then attack when a person reaches out to hit them. Right on Fluffy!

If you encounter a fearful dog in the street and it runs away from you or from another dog which frightens it, and you turn your back towards it to leave, the dog might suddenly come up from behind and nip you, because a fearful dog is motivated to bite and then quickly bugger off. So never turn your back or run away when you encounter a fearful dog. Remain calm and stand your ground!

Defensive Aggression

Just try it and I will bite!

Defensive Aggression is motivated by fear as well and occurs when a dog decides that the best defence is a good offence. It is closely related to fear aggression with the primary difference that it’s the number one strategy adopted by the dog. Dogs who are defensively aggressive are still motivated by fear, but instead of trying to get away from a situation, they have learned that attack is their best way to defend themselves.

Those dog can charge at a person or another dog, barking and growling, when they feel frightened by them. They don’t care if their victim freezes or advances towards them, defensive aggressive dogs often strike first. Only if the other one retreats, they might abort the attack.

This form of aggression is very difficult to deal with as often an attack cannot be avoided unless one instantly understands that this dog will bite first, then deal with the consequences later. Dogs who decided to use attack as their defence are usually quite confident dogs. Rehabilitating them is often a very long process and not always successful.

Social Aggression

Listen everyone, I am the boss here!

So you are happy with sweet lovely Daisy, having enjoyed her company for years and decided that now it’s time to get her another canine friend? What possibly could go wrong?

If your dog inherited social aggression, a lot can go wrong and little Daisy will turn into a monster, threatening and bullying your newly adopted doggie.

Intra-household aggression, which also can be called a social-conflict aggression will keep you constantly on the edge if two or more dogs live under your roof and more than one wants to be dominant.

Living together for more than eight years with Benny, my Kintamani dog from Bali with full of aggression related anger issues taught me a lot how to deal with an extremely independent dog who still thinks that he is the boss. But over the years and many bite wounds later, I learned how to recognise his triggers and how to prevent him from entering the red zone… until I decided that it’s time to adopt Jimmy, a 12 year old Shepard mix dog and Julie, an approximately 2 to 3 year old Kanni dog full of youthful energy from the shelter. The moment I invited them into my house, Benny started to show to me that 8 years of training him was certainly not enough. Every day he finds new ways to display in some form aggressive behaviour towards Jimmy, a former killer dog, whom I rehabilitated completely.

Social aggression is one of the more complex forms of aggression to correct, as the dogs are always living close to each other and thus explore daily new activities and situations, which could trigger a fight. Slowly re-socialising them is the key, until they act more and more calmly with each other.

Even Benny has accepted me as pack leader, bringing Jimmy and Julie into our lives has challenged our established hierarchical order. Every opportunity, be it who first gets it’s food served, who sleeps on the best resting spot, who is allowed to play with sweet Julie first, you name it, everything is turned into an opportunity to fight over, especially as all of my three dogs, as different as they are, all display strong alpha tendencies. Never a boring minute in the house!

But social aggression is not only displayed when new dogs arrive in the house, sometimes dogs show an aggressive response also towards humans, when a dog perceives an action as threatening and unpleasant.

This can include some kinda obvious things like taking it’s food or favourite chew bone away, or disturbing it while it sleeps, but some dogs also react aggressively when one tries to hug or kiss them. Other dogs let you know clearly that it doesn’t like to be lifted up or carried. Bathing, grooming, wiping its face or towelling are high on the list of things dogs don’t particularly like and those with social aggression will let you know clearly what they think about bath time. The list of triggers which let some dogs explode is long and the complexities involved in social aggression are poorly understood and hotly debated by behaviour experts. Some believe that social aggression is rooted in fear, while others think that it is motivated by anger and the desire for control.


Having lived with Benny for so many years, I definitely agree that both sides of the argument are right. Benny pretends to be a tough macho, but in fact is scared of almost everything, even a mouse crossing his way. And at the same time he is constantly angry with everyone and the world. I just accepted this as part of his character and even there is no way to ever cure him, we learned and still learn to control his outbursts and prevent him from crossing over whenever possible into the red danger zone.

And then there is the

Frustration-Elicited Aggression

If I can’t get what I want, better watch out!

A dog who is aroused and excited about something, but is held back from approaching it, can turn aggressive mostly towards the person or thing which is holding it back. What does this mean? Like children, dogs do get frustrated and lash out sometimes using aggression, when they get frustrated by not getting what they want.

When I work in the shelter and train dogs to walk on the leash for the first time, some dogs vent their frustration of being suddenly restricted in their movement by turning around and biting at the leash and some even dare to try to bite my hand. It’s easy to train them that biting the leash or me won’t lead to anything and so far every dog eventually learned to walk on a leash and understood that it’s a wonderful tool of communication and safety.

But what if frustration is accumulated in a dog, which is locked in a cage or behind a gate or god forbid, held on a chain for its whole life? The frustration level in those poor animals reaches levels, which turns their inner life into living hell and cause immense trauma. They react aggressively towards everything and everyone within their reach. Often months, even years of rehabilitation is necessary to help those dogs to overcome their frustrated aggression.

Redirected Aggression

Don’t dare to intervene!

Did you ever try to stop two dogs from fighting and went in between? If yes, it probably resulted in getting bitten by either or maybe even both dogs. That’s an example of redirected aggression which occurs when a dog is aroused by or displays aggression towards another dog (rarely a human) and someone else interferes.

Then the dog redirects in an instant its aggression from the initial source that triggered it to the person or another dog who dared to interfere. This is the reason why people often get bitten, when they try to break up dog fights.


When Benny was younger he often started fights with other dogs and of course, I had to intervene to break up the fight, collecting quite a lot of scars on my hands and arms in the course of a few years, until Benny finally got a bit more mellow. Overtime I learned to remain calm and techniques of how to grab Benny and other dogs when they are in berserk attack mode without getting bitten, but it is still always a gamble if I get injured or not.

Pain-Elicited Aggression

I am so hurt, don’t touch me!

This form of aggression is not caused by fear, but occurs when a dog is in pain. Even a super gently and friendly dog can turn aggressive when it experiences intense pain and discomfort.
In my work as volunteer in a dog shelter, doing a lot of street rescues, I encounter injured dogs almost on a daily basis. Only through experience and using a lot of precaution and by relying a lot on my intuition and understanding of the state of mind a dog is in, I can avoid most of the times getting bitten. The only way to stop this form of aggression is to stop the pain by rescuing, helping and healing the injured dog.

Sex-Related Aggression

Don’t come close to my girl!

A high percentage of dogs which have not been sterilised or castrated will display this type of aggression when a female dog is in heat around them. And also females might turn aggressive when they compete for access to a hot male.


Even when no females are present, some uncastrated male dogs still sometimes challenge each other and fight. In the wild, this behaviour is natural as according to the laws of Mother Nature, the strongest males always get the hottest girls for breeding. But females are not very different from males. If they live together in the same household, they might start competing to establish which one will get access to the strongest male.
Sterilising and castrating dogs help to solve in most cases this form of aggression, but it still takes weeks and sometimes months to see a change in behaviour as hormone levels decrease only slowly.

Predatory Aggression

… have to hunt, have to kill!

Even Fluffy, who snores peacefully in his soft dog bed, might sometimes remember its ancestors and turn into an aggressive predator, when it spots Mr. Squirrel in front of the window running up a tree. In an instant Fluff the mighty hunter is awake, throwing himself at the window, barking madly at its prey, which mocks him by running happily along the branches and not caring a bit about the mighty warrior.

Julie, my Kanni dog, is very well trained and obeys me most of the times, but when we are on a walk and a bird suddenly flies up beside us, there is almost no holding her. In an instant, she turns into the wild hunting dog she actually is and follows her instincts, trying to catch the prey. But as I mostly walk her on a leash, the lucky bird usually escapes unharmed and I manage to calm down my girl quickly.

Julie’s behaviour is not a big issue at all, it’s just all too natural, but what if you have a dog, who lets its instincts run wild by chasing after joggers, people on bicycles, kids on inline skates, skateboards or even hunts after cars? That’s where things really get messy and dangerous.

A dog which enters predatory mode rarely gives off any warning signs before an attack, it wouldn’t make sense in nature anyhow. Out of the blue a predatory dog attacks without growling or showing teeth. This behaviour can become extremely dangerous if in some rare cases the sound of a baby crying or the movement of lifting a baby out of a crib can trigger a lightening-fast reaction from a predatory aggressive dog. Small children should never be left unsupervised with a dog, as there is no holding back if instincts take over a dog and turn it into a predator.

Idiopathic Aggression

I am aggressive, that’s who I am!

Under this term fall all types of aggressions which are unpredictable with either an unknown or misunderstood trigger. Idiopathic means something which „arises spontaneously with no known cause“, which make this form of aggression the most dangerous as it simply cannot be predicted nor is fully comprehended and understood. There might be neurological reasons behind a dog who suddenly turns aggressive. Fortunately this form of aggression is extremely rare.

There are other types of aggression like control-related aggression which is often the result of improper handling by a dog owner who does not understand its dog.

Here you can find general information about Dog Aggression in Part 1 of this post

To find out how to treat aggression please read Part 3.

Author: freakingcat
You can contact me under freakingcat@gmail.com