Whether the aggression is directed towards you, a family member, a stranger, or another animal... an aggressive dog is not only very frightening, but could inflict serious injuries or invite legal action.
While it may seem like your dog is biting you 'a little too' aggressively or displaying other aggressive behaviors out of the blue, most dogs only exhibit aggressive behavior for one of five basic reasons.
In this article, we're going to look at the 5 reasons 'good' dogs become aggressive and how you can stop it forever.
Before we dive in, I think it is wise to point out that dog aggression is rarely cured by training alone.
Dog training classes are fine for teaching obedience, but not dealing with aggressive behaviour in your dog.
Aggression is the realm of a dog behaviourist.
Make sure you employ the services of a professional dog behaviourist that is well versed and an expert in this area of behaviour. The reason is simple: you need a dog behaviourist to identify the triggers involved in what may have caused the aggression in the first place.
Dog aggression is often related to fear, pain, dominance, territorial, diet, a one-incident reaction, illness... The list of possible causes is endless.
Before setting a workable program to overcome this behavioural issue, many factors would need to be taken into account.
The first and most important thing to work out is what the potential trigger was.
For instance, did the dog behave agrressively out of fear, to show dominance, avert pain, or protecting his territory?
Could it be due to changes in the dog's hormones, guarding resources, a one-incident reaction, or is it genetic or a learned behaviour. Along with many other reasons for the behaviour
It is difficult for most humans to read the subtle signals of a dog that is likely to or intend to attack. Majority of us are not equipped to read the body language or subtle signs of canines.
Here's what I mean:
Dogs with tails that curl over the back such as Chows and Akitas or dogs with drooping ears like the Weimaraner do not give the same signals of say a Collie or an Alsatian.
Some breeds do not display the classic erect tail and ears pulled back when they're provoked.
This is also the case with hairy or Spitz type breeds.
In these circumstances, the signs may be obvious but since they're not what we know or expect... we do not notice them and, as a result, fail to avert an attack in time.
This is one of the reasons why majority of dog attacks are to family members, neighbours or people the dog owner knows.
One sad fact about dog attacks is that children are often the victims.
Majority of facial reconstructive surgery performed on young children is less a result of car or other accidents as many would believe, but predominantly from dog bites.
The choice of dog also has a marked effect on whether dog aggression or bites may occur.
The guarding breeds tend to guard, the herders tend to herd, and the retrieving dogs predominantly retrieve. Therefore if a dog was bred to guard, it shouldn't be surprising if they bite when provoked.
It is unusual for a dog to suddenly attack for no apparent reason - i.e attacking out of the blue.
Such incidents are unheard of, except where medical causes or injury are the trigger.
However, we all know or have heard of the person who say, “Oh he has never done that before” when their dog attacks another animal or nips someone's ankle.
Then the dog does it again and they uttered exactly the same words. Owners often go into denial over their dog’s bad behaviour.
A lot of dog bites and aggressive tendencies are brought on as a result of owners excusing bad behaviours of specific breeds.
This is because they perceive aggression (which usually starts small) is the normal "acceptable" behaviour for breeds such as the Terrier, the nipping Collie, or the growling miniature breed.
With this mindset, the dogs is not checked when the aggressive behaviour is first observed in small doses, leaving room for the trait to become stronger and eventually difficult to treat.
The longer you pander to aggression, the stronger the trait becomes until finally it is next to impossible to change this behaviour.
In my 35+ years of training dogs, what I have discovered is that the majority of aggressive behaviours are fear-based. Although we often categorise them as Territorial, Protective, Predatory, Sexual and Nervous/Fear Aggression.
If you think your dog's bouts of aggression is fear-based don't rush out and have it neutered. Neutering a dog without dealing with the underlying cause of aggression often heightens aggression rather than curtail it.
We have all come across advice mostly from the internet, "Oh just neuter the dog. That should fix the problem". Advice like this has caused more dogs to be euthanised than almost any other comment.
Neutering can help male dogs, especially when they keep fighting other intact male dogs.
It never helps with female dogs and, more often then not, makes aggressive tendencies considerably worse. If the aggression is directed at both male and female dogs, then it is most likely fear-based. Therefore don't be in a rush to have your aggressive dog neutered.
Ask an experience dog bahaviourist about fear-based aggression. Don't listen to the armchair experts, and most Vets who know nothing about behaviour and have a strong financial interest in neutering.
Most dog aggressive tendencies have their roots in early games and contact with humans and other dogs or pets.
That's why early socialisation with other puppies before 16 weeks of age is an absolute must. This is because puppies learn long-lasting, unconscious behaviours during the 0-16 weeks mark, making it a critical period in a dog's life.
Puppies learn to communicate with other dogs not when they've grown into adults but from pups of a similar age. To prevent or minimise the likelihood of aggressive behaviours due to poor socialisation, pups should interact with, play, and be handled from birth to 16 weeks by at least 20 different people including children.
Taking responsibility and controlling game sessions and structured dog walks should give a dog owner control over each dog and help both in the short and long term this type of unacceptable behaviour
Intact non-neutered males are more likely to exhibit dominance aggression (but only against other intact dogs) than neutered males or spayed females. It is more likely that this is controlled by androgen since females who show aggression before puberty and who are spayed become more aggressive.
The most common aggression cases I treat are fear aggression and protective aggression.
This is generally social in context and can occur between dogs within the same house. This type of aggressive dog behaviour is rarely hormone driven.
And, it doesn't always start at social maturity (12 to 24 months).
What usually happens is that one dog feels challenged by a stare, a bump, blocked path, or body block... and then each dog behaves in reaction to what the other dog did.
If this behaviour is not addressed early enough, it will escalate into an all-out war.
Dogs in this situation can end up hating each other - even though they have been the best of friends or siblings just weeks prior.
I have witness some households perform what seems like military operations in a bid to prevent two aggressive dogs from meeting each other.
When the issue has got to such stage, unless you bring in someone who understands how to work with these types of aggressive dogs (I have done hundreds of these cases)... you will have no choice but to euthanise or try and re-home one of them.
The key here is early intervention.
If two dogs start fighting just because they have seen each other, then it is generally caused by fear of which the root cause is protective aggression.
One of the characteristics of interdog aggression is that the aggressive intentions do not exist or are barely noticeable with other animals. The dog may live peacefully with cats, horses, and other animals or pets.
This can be stimulated by sudden movements. Someone in the room suddenly gets up. That action can trigger an aggressive response.
Most dogs inhibits the behaviour in the absence of its owners or the person, child or dog it feels the need to protect from harm - no owner to protect, no protective aggression.
Such dogs can be non-reactive in strange places (dog shows for instance) where there are lots of dogs or people.
In circumstances like these where they are flooded with potential threats, they cannot identify and lash out at a specific threat. And, as such, the behaviour does not occur.
Sometimes a dog will protect people or animals they think is vulnerable. These dogs do not show any aggressive behaviour until a puppy or new baby is introduced into the household.
They may be fine indoors but then become very protective outdoors from strangers or other dogs or vice versa.
This type of aggression is not specific to any sex as male and female dogs can display protective aggression - especially nursing dogs.
Protective aggression usually starts at social and mental maturity. The timing depend on the breed, but on average it occurs between 1 and 3 years of age. The larger of the breeds the older it will be before this type of behaviour occurs. Puppies rarely show this trend.
90% of hormonal aggression cases occurs in male dogs.
It first becomes obvious at social maturity (12 to 24 months), worsens with punishment, and may be hereditary. This is the type of aggression that dog breeders look out for at the 8 week puppy test.
Hormonal aggression is identifiable at 8 weeks and early intervention can to save the dog. However, not all dogs with dominant aggression can be identified at 8 weeks.
Most of us have dogs who to some extent display signs of territorial aggression: our dogs bark as people pass on the pavement, protect the car, and bark when someone's at the door.
All social animals exhibit some protective aggression .
This behaviour is increased by fences; the dog is able to continuously "patrol" and protect. The behaviour can be made worse if the dog is enclosed in say an electric fence or chained up.
It can also be made worse if "door greeting" abnormalities are tolerated: the owner greets someone at the door with the dog held back whilst straining on the collar whilst possibly barking and growling.
This is considered a concept of control, unlike aggressive possession of an object (food or object aggression) or challenge (will the dog get off the sofa or growl?).
Dominance aggression is more common with male owners who like the concept of "big, tough dogs" and so some breeds might be more likely to be diagnosed with this problem. But some of the worst dominant aggressive dogs I've dealt with have normally been Toy Poodles, Chihuahua's and Shih Tzus.
This is because their Behaviour is more likely to be seen as cute and innocent - until it's not!
There are some 15 things people do to exacerbate dominance aggression. Something as simple as staring at the dog or pushing on their rump, leaning over them, making a lead correction.
There are over 20 signs that the dog intends to become dominant aggressive.
That could be as innocent as standing on your feet, leaning against you, talking back, standing in front of you in the doorway, jumping on your lap.
These signs are often tolerated in smaller dogs. Why? Because owners think it's cute.
And I don't blame them. As humans, we are programmed to preceive the actions of smaller creatures as less threatening.
Though these smaller dogs may not do as much damage as say a Mastiff, that should not excuse from being aggressive.
Dogs with dominance aggression are categorised in behaviour as those who think they are Alpha's - able to control people and get things their own way - a bad, prognosis usually.
And then there are those dogs where all the signs were there and we allowed them to get away with it.
First, although other aggressive behaviour is not a predictor for dominance aggression... dominance aggression is about control, and the dog generally has other forms of aggression too.
Strangely enough, a common trait is that dominant dogs can also be very sensitive, they can also have fearful and anxious behaviour.
That could almost class them as schizophrenic.
Second, when the dog has escalated through several signs of dominance aggression - standing on people, sitting in laps - and it's allowed by the owner, then the dog starts thinking he's in charge... like when a teenager starts to talk back to test boundaries.
This class of dogs will alter its Behaviour to the individual.
The dog may not behave aggressively with an experienced trainer (the trainer is in charge), or when it's eating it may not bark at people passing by.
The dog can interrupt and inhibit the aggressive behaviour, but chooses its time when not to react. This actually is the easiest dog to work with since the dog is capable of taking cues from context and behaving appropriately.
However it would be extremely difficult to determine the exact genetics for this behaviour, since development of the behaviour depends not only on the genes but also the dog/owner situation.
If the dog was genetically predisposed but owned by a good trainer and discouraged at an early age from barking at say the door, it may not exhibit the trait ever again
On the other hand, a dog who may genetically be less predisposed but encouraged to exhibit the behaviour, it then can become a major problem.
Taking a reactive dog for a walk is one hell of a job.
The second a reactive dog sees another dog or strange-looking object... he’ll start barking, growling, lunging, and pulling in the direction of whatever caught his attention.
For most dog owners with this problem, their dog grows so reactive they prefer walking the dog at odd hours or not take it for a walk at all.
If a reactive dog is not taught how to calm down, their reactive behavior is sure to escalate.
It can get to the stage where owner and dog just sit at home in the hope that another dog doesn’t walk past the window.
Or worse...
The dog’s reactivity becomes so out of control, the only solution is parting ways with an otherwise-lovable four-legged friend.
If this sounds like the unavoidable nightmare you and your dog are heading for, you are not alone.
Thousands of dogs get abandoned to rescues every year or even put down due to aggressive behaviour. More often than not, the truth is your dog is not aggressive - He's simply afraid.
The good news is, there is a cure for fearful dogs.
Whether it's fear of other dogs or fear of humans, this is a resolvable issue.
With appropriate training and behavior modification, you and your furry friend can enjoy the freedom of a pleasant walk together.
But...

Before we can begin to resolve the issue, it's important to understand why your dog is reactive.
Firstly, let's rule out illness and chronic pain. Some dogs -- much like humans -- can suffer from a disease, aching joints and arthritis, especially as they get older. If you have an older canine who has recently become reactive to other dogs, a trip to see the vet might in order.
Arthritis and joint pain in older dogs is usually manageable. With the right treatment, you might find that your dog’s behaviour returns to normal on its own.
Once you’ve ruled out any medical concerns, there are endless reasons why your dog is a reactive dog. The typical case, however, is that your dog feels threatened. By snarling and barking at the thing he finds scary, he is trying to tell the thing (canine or human) to back off and not come any closer.
If your dog is displaying signs of fear by reacting to other dogs, or even other humans, the worst thing you can do is dole out punishments. Aim to support your dog by preventing him from practising reactive behaviour.
For example, plan to exercise your dog in less crowded places or at less busy times of the day. If the sight of another dog is a stress trigger, then turn and walk away. Your dog will not be afraid if it can't see what he's scared of.
Dogs can sense when you’re stressed and anxious.
Most people with a reactive dog will immediately tense the lead and pull the dog towards them at the mere sight of their dog's trigger. By shortening your dog’s lead or pulling him towards you before he's even had a chance to react, will reaffirm his fears.
If you have concerns about not being able to control your dog on a regular lead, then it might be worth investing in a no-pull harness.
When walking your dog, you have to remember that your dog will respond to your energy and demeanor. If you are tense and gripping the lead tightly, this can cause your dog to become agitated and anxious.
Additionally, raising your voice can also escalate ANY situation and make things worse.
Instead, approach the walk with a calm and relaxed attitude. This will make the experience more enjoyable for both you and your dog. You can achieve this by training your dog to walk calmly on leash before taking him to crowded or unfamiliar places.
While on a walk, be mindful of your dog's body language and adjust your own behavior accordingly. If your dog seems anxious or nervous, it can help to slow down your pace and give him some time to sniff and explore his environment.
Overall, walking your dog should be an enjoyable and positive experience for both of you, and by keeping a calm and relaxed attitude, using positive reinforcement and understanding your dog's specific needs will lead to a more enjoyable walk for all.
When you notice your dog getting reactive on a walk, try to redirect his attention to something positive - like a toy or treat.
This way, he has something else to think about besides the thing that scares him. Play mini training games of touch or watch, with regular treats and praise for good behaviour.
Situations like this is where positive reinforcement training comes in handy, especially when teaching your dog to walk calmly on a leash.
3. Change your route.
Keep things interesting for him (and for you!). This is crucial as it ensures that his daily walks remain engaging and stimulating.
One way to do this with a reactive dog is by providing new and varied experiences: if you two have been walking the same path for an extended period, it's likely that your reactive dog (and yourself) have become bored with the routine.
In order to maintain your dog's interest and engagement, it is essential to introduce new sights and smells.
One way to change things up is to explore new neighborhoods or parks, where your dog can discover new sights, smells, and even other dogs to interact with. This not only keeps your dog mentally and physically stimulated, but it also provides you with a new and exciting walking route - I mean, you also want to enjoy walking your dog, right?
Additionally, you could also bring different toys and change the route of your walk during different days, so it'll take him by surprise - which will be interesting for you.
Overall, keeping things interesting for your dog is essential to ensuring that their daily walks remain engaging and stimulating. By introducing new sights, smells, and experiences, you can keep your dog mentally and physically stimulated and make your walks more enjoyable for both you and your dog.
Another way to keep things interesting for your dog is to incorporate training or obedience exercises into your walks. This can include basic commands like sit, stay, come, or heel, or more advanced tricks like rolling over or playing fetch.
By adding an element of training to your walks, you will keep your dog mentally engaged and provide him with a sense of accomplishment.
You can also try walking your dog at different time of the day. This can change the sensation and the ambiance of the place, and also change the way your dog interacts with the environment, making the experience different and unique.
5. Be A Fun Person To Be Around!
Change your pace; speed up and slow down. Walk in circles, weave around lamp posts and trees. Your dog won’t be so worried if his human is fun to be around.
By making the walk more interesting, your dog will enjoy spending time with you.
Sometimes it's best to avoid putting your dog in a stressful situation.
While walking your dog, stay alert! Try to recognize when a situation may be too much for your pet to handle. If you come across an aggressive or overly stimulating dog while out for a walk, it may be best to avoid the encounter for your pet's well-being.
Being proactive and removing your pet from the situation can prevent any potential stress or harm. Your pet may not be able to express gratitude, but they will appreciate your consideration.
Every dog is different and may have unique needs.
Some dogs may require more exercise or a different type of training. Therefore, it is essential to get to know your dog and understand their individual needs to ensure that you are providing the best possible experience for them.
Having said that, owning a reactive dog is frustrating and socially isolating. It can make you feel like a pariah in your own neighbourhood.
As an experienced and qualified dog behaviourist, I can help you to resolve common problems such as reactive behaviour in as little as two comprehensive training sessions. You can start to improve your relationship with your dog today.

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