How to Learn the Signs of Aggression In Dogs · The Wildest

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How to Learn the Signs of Aggression In Dogs So You Can Get Them Some Doggy Therapy

Experts agree: breed doesn’t have anything to do with it.

A persons arm around a dog in a park.
Photo: Gabriel (Gabi) Bucataru / Stocksy

Not a week goes by that I don’t get asked what kinds of dogs I think are the most dangerous. When people wonder about the “kinds” of dangerous dogs, they typically think about breeds. But breed doesn’t have anything to do with it. People should focus on individual dogs and specific circumstances rather than a dog’s breed.

Dogs rarely, if ever, bite without warnings, and sometimes those signs of trouble have been going on for months or even years before the bite happens. Here’s the thing: the problem isn’t unpredictable dogs. It’s misunderstood dogs. Dogs often try hard to communicate that they are uncomfortable or don’t like what is happening to them. But if nobody understands those messages, the dogs continue to be in situations that make them unhappy, and some of those dogs may end up biting.

As a professional behaviorist and trainer, I know we need to better educate people about the red flags of potential aggression in dogs. Red flags exist but are not always picked up on. Here’s what you need to know about dangerous dogs.

Five most dangerous dogs

While not every dog in these categories is dangerous, it’s important to be aware that there is an increased risk of dog bites when dealing with these types of dogs or dogs in these situations.

1. Fearful dogs.

Dogs who are scared, nervous, or anxious may panic and act aggressively in order to protect themselves. And remember, a wagging tail does not mean that a dog is friendly. Being afraid is at the root of more dog aggression than any other factor.

2. Untrained dogs.

If a dog has no boundaries and has never been taught how to behave, they are more likely to injure someone — perhaps by accident. People (especially children) are often bitten, scared, or hurt by dogs chasing them or jumping up on them.

3. Unpredictable dogs.

If a dog’s behavior is confusing and does not follow any obvious pattern, it’s easy to be taken off guard by their actions or inadvertently do something that upsets them. Don’t touch a dog who is sleeping, eating, or chewing a toy. Respect their space — startled dogs are more likely to bite.

4. Tired or sick dogs.

Just like people, dogs are not at their best when they don’t feel well and most would prefer not to be bothered. Dogs don’t have many ways to let us know that they’re in pain or that they want to be left alone. They sometimes resort to a growl, snap, or bite, especially if they’ve already tried to walk away and go off by themselves, and that didn’t get the message across.

5. Unfamiliar dogs.

Not all dogs consider everyone a friend immediately. Many dogs need time to warm up to new people and don’t like being treated as a long-lost friend within five seconds of being introduced. Treating an unfamiliar dog like your best friend can be off-putting to some and lead to aggressive behavior. If you adore all dogs, remember that the feeling of love at first sight may not always be mutual.

Are certain dog breeds more dangerous?

Stereotyping breeds to predict aggressive behavior is not useful or fair. The predictability of aggression based on a dog’s breed is highly overrated. The idea of breed bans or rejecting certain animals simply because their relatives have misbehaved is not going to get us anywhere.

Certain breeds are getting more bad press than they deserve, and aggression is a stereotype that seems to stick, even if other generalities are fitting. For example, most people with a Pit Bull know their pitty is more likely to lick an intruder to death than bite them. Yet, most of what we hear about is Pit Bull aggression, not excessive licking. Rottweilers and Dobermans are also breeds that many people fear on sight without any actual data about the particular animal in question.

On the other hand, there’s no denying that certain lines of dogs that have been bred for aggression do exhibit it. Regrettably, aggression is easy to breed for if that is someone’s intent. However, not all members of breeds who have been bred for aggression are from lines with that sort of breeding history. Nurture is key, and anyone can make a fearful, aggressive dog with improper care.

In my experience, some dog breeds who more commonly have aggression issues are Golden Retrievers and Labrador Retrievers. Are these bad dogs? Aggressive breeds? Of course not. They are just common breeds, so statistically are more likely to be noted as aggressive. Any breed can have an aggression issue. Aggression is far more predictable based on a dog’s previous behavior than on the breed.

Why do dogs bite?

It’s important when working with an aggressive dog to understand as much as possible about why the dog is biting. Some dogs bite because of fear, because they feel threatened, because they’re in pain, or they feel overwhelmed.

Dogs use their mouths both playfully and not so playfully as puppies, and the vast majority of them develop normal bite inhibition — an understanding of what they are and are not allowed to do with their mouths. Biting is a normal part of canine behavior. While people are more inclined to hit when behaving aggressively, emotions such as anger and frustration combined with high arousal are typically involved with dogs who bite in an out-of-control way.

Such bites happen when dogs have the canine equivalent of a toddler’s tantrum because they don’t get what they want. Dogs who bite in these contexts are literally unable to control themselves. It is much harder to substantially improve their behavior compared with other dogs, most of whom are biting as a result of fear.

Signs of aggression before the bite

Some dogs already have a bite history towards dogs or people and that’s a clear warning it could happen again — especially if it was an attack that was prolonged and hard to stop. Such relentless aggression is a serious red flag that the dog has trouble with inhibition.

Other typical warning signs that a dog may bite include growling, barking, lunging, tooth displaying especially with an offensive pucker, a tendency to get frustrated, difficulty calming down after getting revved up, going stiff, tongue flicking, charging at anything of interest, hard stares directed at another individual, facial expressions indicating nervousness or discomfort, becoming mouthy when in an aroused state, excessive sniffing of the ground in social situations, guarding food or toys and being fearful of people, animals, or any other object.

What to do if your dog has signs of aggression

Any of these signs, or even the general feeling that something is amiss, warrants a consultation with a person trained to deal with serious behavioral problems in dogs, such as a certified applied animal behaviorist, trainer, or veterinarian board certified in behavior. It’s better to get ahead of aggression with good training.

It’s also helpful to get an outside perspective on how you interact with your dog and your home life, or other environments you spend a lot of time with your dog in. Often, aggression comes from stress or fear, and it may simply be a matter of de-stressing your pup’s life.

There’s hope for the overwhelming majority of dogs with a bite history, as many are able to improve their behavior with a combination of behavior modification and a sensible management plan for prevention. However, there is the rare dog whose likelihood of improvement is small because of a lack of any kind of self-control and the tendency to bite when frustrated, angry, and aroused.

Give your dog some grace, and some care, and these are hopefully issues that never go beyond a warning growl.

Karen London holding up a small dog

Karen B. London, PhD, CAAB, CPDT-KA

Karen B. London, Ph.D., is a Certified Applied Animal Behaviorist and Certified Professional Dog Trainer who specializes in working with dogs with serious behavioral issues, including aggression, and has also trained other animals including cats, birds, snakes, and insects. She writes the animal column for the Arizona Daily Sun and is an Adjunct Professor in the Department of Biological Sciences at Northern Arizona University. She is the author of six books about training and behavior, including her most recent,  Treat Everyone Like a Dog: How a Dog Trainer’s World View Can Improve Your Life.

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