Fear vs. Aggression

You’re walking down the street when you come face to face with a growling dog. You stop short and quickly run through your options. Can I befriend this snarling dog?  Can I out muscle or outrun him?
At the same time, the dog is thinking: Can I outrun this person? Can I escape somehow?  Should I grab a mouthful of leg?

A growling dog can be frightening. But the dog may be growling because he is frightened of you. This begs the question: is the scary dog truly aggressive or just scared stiff?

What is aggression?

Aggression refers to a series of behaviors that dogs exhibit for a variety of reasons. For example, dogs become aggressive if they feel threatened. Female dogs aggressively protect their pups. Dogs are also aggressive when protecting their territory, whether that be a nest in the wild or your home in the suburbs.
The cause of the aggressiveness may vary, but the physical signs of aggression are pretty consistent. A dog that poses a threat to people will usually:

  • Stand still in a rigid posture.
  • Curl his lip, exposing teeth.
  • Growl with a deep guttural sound.
  • Maintain eye contact.
  • Lunge toward or snap at the person without making physical contact (a warning).
  • Grab part of the person’s body without applying pressure (mouthing).
  • Bump the person with his muzzle. No bite involved here either.
  • Quickly nip the person leaving a mark or tear in the skin.
  • Bite roughly and repeatedly.
  • Bite and hold while shaking the person.

The key to dealing with aggression is recognizing the warning signs at the top of the list before a bite occurs.

What are the different kinds of aggression?

Dogs exhibit aggressive behaviors when they feel threatened. Here are the recognized types of canine aggression:

Territorial Aggression: When their territory is invaded, dogs may attack an intruder.
Possessive Aggression: Dogs guard their possessions and act aggressively if they feel another animal or person wants to take away their food, toys, bed, etc.
Protective  Aggression: Likewise, dogs guard their family members and will become physically protective when they perceive a threat.
Pain-related Aggression: A usually gentle dog may act aggressively when in pain.
Predatory Aggression: Some dogs display inherited tendencies to hunt and grab or chase any fast-moving object, including people.
Social Aggression:  Dogs that think they are “boss” of the household may be aggressive toward other family members.
Sex-related Aggression: Both sexes may become aggressive during breeding season, when male dogs compete for a female or a female fights for access to a male.
Fear Aggression: A dog that is afraid may become aggressive if he feels cornered or trapped.

Is fear aggression really aggression?

Fear aggression may be confusing. Dogs that are fear aggressive are not “bad” dogs. They are scared dogs. Fear is a psychological state in which a dog feels uneasy and panics.
Here’s the difference between fear aggression and the myriad of other aggressions. The fearful dog is not the actual aggressor—he is the victim of his fear. However, even though he is afraid, he may lash out at the cause of his fear. The outcome may be the same (injury), but the distinction is important when trying to treat fear aggression.


To treat fear aggression, the dog must become aware that the source of his anxiety poses no threat. Reaching this goal takes time, patience, and often, professional help. Although it’s still a form of aggression, it’s good to have a general understanding of fear aggression.

What does a fear aggressive dog think?

A dog with fear aggression feels threatened and afraid. He wants to avoid the threat and may passively withdraw. If he can’t find an escape route, he panics. He trembles and may lose control of his bladder and bowels. His heart rate increases and his respiratory pattern changes. He thinks he’s trapped and must attack to survive. Fear biting happens when a dog feels extremely vulnerable, not dominant as in other types of aggression.

What are the warning signs of fear aggression?

A fearful dog will not look like an aggressive dog. Aggressive dogs try to look large and threatening. Fearful dogs try to look small and invisible. A scared dog will usually:

  • Tuck his tail instead of standing straight and rigid.
  • Crouch down with his rump lower than his withers.
  • Lay his ears flat.
  • Avoid eye contact.
  • Yawn to relieve his tension.
  • Pant.

Should we be scared of scared dogs?

YES! When a person crosses paths with a fearful dog, he should back off slowly and give the dog a way out. Making the scared dog feel less trapped may diffuse the situation. It’s best to fight the human tendency to comfort the scared dog because approaching, even with the warmest intentions, may be perceived as an aggressive act.
Regardless of the reason, aggressive dogs pose a danger to humans. Like us, dogs inherited a strong instinct for “fight or flight” when faced with a threat. A fearful dog wants to escape, but if he can’t find a way out (flight), he may choose to stand his ground and fight off the threat, i.e., you.

Is there hope for aggressive dogs?

Treating aggression is challenging. With the risk of injury ever-present, it’s best to address the situation “aggressively”.

Consult your veterinarian and animal behaviorist for help. These two individuals can provide essential professional guidance. They will likely recommend some form of behavioral modification therapy, in conjunction with behavioral modification drugs. Medication alone is not the solution. Behavior modification is a must.

And there may never be a solution. There is no guarantee that an aggressive dog can be “cured”. Aggression may be reduced but not eliminated, which means that owners of aggressive dogs must always be on alert.Constant vigilance to avoid the dog’s exposure to situations, people, or animals that trigger the aggression is key.

This client information sheet is based on material written by: Lynn Buzhardt, DVM
© Copyright 2015 LifeLearn Inc. Used and/or modified with permission under license.