Dog bites send an average of 885,000 people to the hospital every year, according to the Centers for Disease Control and Prevention. Children, adult males, and dog owners face the highest risk of being bitten. If your dog’s behavior concerns you, it’s important to recognize the signs of aggression so you can seek proper treatment immediately. Correcting an aggressive dog’s behavior requires professional help from a trained animal behaviorist or professional dog trainer.
A dog’s body language can give helpful clues about its intentions. Aggressive dogs often keep their bodies rigid and still before attacking. They might also wrinkle their muzzles and bare their teeth. Dominant dogs will challenge people or other animals with direct stares. Dogs with fear aggression will cower and assume a fearful posture when they perceive someone as a threat. These dogs will make themselves as small as possible by tucking their tail between their legs and folding their ears flat against their heads. Fear-aggressive dogs prefer to retreat, but will bite when cornered. A dog with defensive aggression will try to seem larger by holding its ears up and its tail high.
Growling and guttural barks indicate aggression in dogs. These behaviors serve as vocal warnings in dogs that are about to attack. A dog with territorial aggression will signal its presence by barking at intruders before going after them. If a dog is defensively aggressive, it will growl and bark at a person or other animal before moving in to attack. A dog with this type of aggression sometimes gives high-pitched barks out of fear or uncertainty. A dog with predatory aggression will give no warning before taking off after prey.
Charging occurs often in aggressive dogs, but the reasons behind this behavior vary. A dog that charges at people or other animals entering its home or yard is exhibiting territorial aggression. A dog with defensive aggression will charge at a person or animal that frightens or intimidates it. A dog with predatory aggression will chase prey, which is usually a smaller animal. Lunging at a person or other animal without making contact is another common sign of aggression.
Biting can be the most serious and harmful sign of aggression in dogs. Bites can range from rapid nips to powerful bites that cause bruising or wounds. A dog with fear aggression will deliver quick nips or bites, usually from behind when a person or other animal turns its back. A dog with defensive aggression will often bite once and wait to see how the victim responds. If the victim backs off, they will usually retreat instead of continuing to attack. Dogs with predatory aggression will bite and shake their prey when they catch it. They usually refuse to let go until they kill their prey. Many aggressive dogs also snap. Although snapping doesn’t involve physical contact, the behavior indicates aggression.
A dog with dominance aggression will often use mouthing with little pressure or a “muzzle punch” to demand attention. When a dog mouths, it places its teeth on a person’s body without breaking skin or biting. A muzzle punch occurs when a dog pushes its nose against a person’s body. Dogs that are challenging their owners for control or have already established dominance in the household exhibit these types of behaviors.