How Do I Fix My Dog’s Aggressive Behaviors?

Written by: Dr. Katy Nelson

March 6, 2019

The dog in the above photo is throwing out some serious side eye. Did you know wide, darting eyes could indicate distress and may be a sign of impending aggression?

All animals have the capacity for aggression – including humans. For dogs, acting out aggressively is usually a result of fear, pain, confusion or instinct. While most pups never escalate to harming another pet or person, your dog’s aggressive behaviors should be taken very seriously. In order to fix the problem – and keep from making it worse – you must first understand your dog’s triggers.

What Causes A Dog’s Aggressive Behaviors?

Some dogs react with joy and affection when meeting a new person or pet, others turn inward and behave aggressively. This certainly does not mean one dog is “friendly” and the other is “mean.” It just shows that dogs are individuals, and some need more help acclimating to social situations than others.

Dogs that display aggressive behaviors typically do so as a result of one or more of the following triggers:

  • Fear
  • Past Trauma
  • Pain or Illness
  • Cognitive Problems
  • Possessiveness
  • Frustration
  • Dominance

dogs aggressive behaviors

What Are The Signs Of Aggression In Dogs?

Most people know how to recognize the more obvious signs of aggressive behavior:

  • Teeth bearing
  • Growling
  • Snarling
  • Snapping
  • Biting
  • Lunging

However, those who are unfamiliar with canine body language may overlook the more subtle signs of distress such as:

What Are The Different Types Of Canine Aggression?

Fear Aggression

Fear is probably the most common cause of dog fights and aggressive behaviors towards humans. Just like any animal, dogs experience fear when threatened or backed into a corner. Most prefer to flee, but if escape is not an option, they will fight for survival.

fear aggression


Our dogs’ wild ancestors are territorial, and the desire to protect their “den” still lies within even the smallest domestic pups. Territorial pups often bark and charge at dogs, people or other animals they feel are getting too close to their turf. While some dogs are territorial of the yard or property line, others behave aggressively when another dog or person enters the home.

Resource Guarding

A dog’s aggressive behaviors often stem from a desire to guard the possessions they hold most dear. These may include food, chews, toys, or even favorite humans. Resource guarding likely stems from survival instinct and competition for food instilled by their wild cousins. Also, dogs really love food, chews, toys and their humans!

resource guarding

Protective Aggression

Dogs are extremely social and will go to great lengths to protect the members of their pack, whether human or fellow canine. This is often seen when a mama dog has a litter of pups or a family brings home a new baby. While protective aggression may sound appealing – who doesn’t want a personal bodyguard? – some dogs are overly protective or react to innocent people, pets or actions.

Dominance Aggression

Dogs are social animals, and as with any group of individuals living in close quarters, dominant personalities are bound to emerge. Dominance aggression is common in multi-pet homes, but may also occur between two like-minded dogs challenging each other for status.

dominant behaviors

Frustration Aggression

When a dog is excited by something they see or hear but cannot get to, they may act out aggressively. This is often seen in on-leash dogs, dogs behind fences, and those inside homes looking out onto the street. The reactive dog wants so badly to get to the source of stimulation, that they snap or lunge at that animal or any human or pet in their vicinity.

It is very unnatural for dogs to greet each other on-leash. Being restrained leaves them feeling vulnerable. They may also respond to your stress in these situations. On-leash greetings are a big no-no for dogs with aggressive behaviors.

Pain-Related Aggression

If your dog’s aggressive behaviors are new or sudden, your pup may be suffering from pain. Before jumping to behavioral correction, see your veterinarian for a thorough exam. Your dog may be sick or experiencing a painful condition like arthritis.

On a similar note, dogs suffering from cognitive problems or conditions affecting the brain may also act out with sudden aggression.

pain aggression

Sex-Motivated Aggression

Intact dogs of reproductive age may become aggressive and compete for attention from the opposite sex. Spaying, neutering and preventing your dog from roaming the neighborhood can easily prevent this form of aggression.

Predatory Aggression

It is hard-wired in dogs’ brains to chase and prey upon smaller animals including cats, ferrets, birds, squirrels and other pocket pets or wildlife. Predatory aggression may also cause them to chase after cars, bicycles, skateboards, and joggers.

predatory behaviors

Dog-On-Cat Aggression

There are several possible reasons for a dog’s aggressive behaviors towards cats. They may have had a bad experience with a cat in the past, or see the family kitty as competition for food, territory and human affection. Others may simply be acting on their natural prey drive, but no matter the cause of dog-on-cat aggression, there are solutions.

First, make sure both the cat and the dog have “safe” spots within the home. For the dog, it is usually a good-sized crate in a separate room where they can go when overwhelmed. For the cat, try a high cat tree or gated-off area the dog cannot access.

In addition, dogs with strong prey drives, and/or aggression towards smaller animals must receive obedience training, followed by careful socialization training. A certified professional dog trainer can help you recognize aggressive body language before your pup strikes, allowing you to intervene and prevent an attack. They can also give you the tools to redirect your dog’s energy for a calmer mindset.

When ready, slowly expose your dog to the cat in a safe environment where the cat can escape if necessary. Many trainers do home visits and can help you socialize your inter-species pets.

dogs aggressive behavior towards cats

Dog-on-Human Aggression

This is the most serious type of canine aggression, and requires immediate intervention. Not only could an innocent person be injured, your dog could be at risk for euthanasia. Many of the categories listed above can lead to dog-on-human aggression. Fear is the most common cause, but resource guarding, protective or possessive behavior, frustration, and pain-related aggression can also lead to attacks on people.

How Can You Fix Your Dog’s Aggressive Behaviors?

Whenever a dog has shown aggressive behaviors towards people or other animals, it is crucial to seek professional help. Your first priority should be to see your vet and rule out any medical or cognitive issues. They can recommend a veterinary behaviorist or professional trainer with education and experience dealing with aggressive dogs.

Aggression is a very serious problem, and until the root cause is addressed, your dog may be a danger to you and others. While you should never attempt to resolve the issue on your own, the following tips may help prevent further incidents as you seek help.

  • Provide LOTS of exercise, especially to highly reactive pups
  • Socialize your puppy or rescue dog
  • Avoid on-leash greetings
  • Do not force shy or timid dogs into social interactions
  • Avoid overly arousing play situations
  • Never use aggression or intimidation to correct your dog
  • Work on simple commands like getting your dog’s attention in public
  • Give other dogs a wide berth on walks
  • Do not allow people or other dogs to invade your pup’s space
  • Consider a basket muzzle for walks
  • Remove desirable items that may cause resource guarding
  • Do not encourage protective or territorial behavior (For example, yelling “Get him!” when another dog walks by the window)
  • Always reward good behavior

Looking For More Articles Like This?

Dog Communication: What Does A Dog’s Body Language Mean?
Clicker Training: How Do I Use It To Communicate With My Dog?
My Dog Is Biting: How Do I Get Them To Stop?
How Do I Find A Trainer For My Dog?

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Written by: Dr. Katy Nelson

March 6, 2019

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