5 Signs of Aggression in Dogs

If your dog is spending a lot of time with another dog or visiting a dog park, you should brush up on the signs of dog-on-dog aggression. Knowing what to look for when dog play turns into a dog fight can help keep your pet safe.

Bared teeth, growling, tense body language, biting, and avoiding eye contact are signs of dog aggression. If you see your dog or another exhibiting any of these signs, separate the dogs and give them some space to cool down.

One of the major signs of dog-on-dog aggression is when a dog bares its teeth. This is a warning sign your dog is giving to the other dog to back off. Dogs are social creatures, so they try to communicate with other dogs and animals through their body language to diffuse the situation before it gets out of hand.

If your dog is feeling threatened, scared, or overwhelmed, he may bare his teeth to tell the offender it's time to stop. Your dog may also lick his lips and yawn to communicate displeasure.

2. Growling and Snarling

Another way dogs communicate is with sound. Barks and different noises can tell you and other dogs how your canine is feeling. When your dog growls or snarls, he says that he is uncomfortable. It is another warning that if the offender doesn’t back down, your dog will become aggressive.

3. Flattened Ears, Tucked Tail, and Stiff Body

Your dog communicates with every part of his body. When he is feeling frustrated or scared, his body will be tense. His tail will tuck, and his ears will flatten. His face will wrinkle, and he will appear very stiff. Your dog may also curl his lip and freeze in place.

Some dogs are more reactive than others. For instance, guardian dog breeds (like the Great Pyrenees) are more likely to respond to perceived threats than laid-back dog breeds (like Irish Wolfhounds).

So, reactive dogs may exhibit these aggressive behaviors in response to certain stimuli, such as certain types of people, children, or other dogs. Dogs with these behaviors may have past trauma that influences this aggressive behavior.

A sure sign of dog aggression is when a dog bites, snaps, or lunges at you or another dog. When a dog bites, it intends to cause injury. Biting is an instinct that dogs have in response to danger, and it is also how they hunt. So, when a dog gets to the point where they are ready to lunge at another dog, they are ready to bring blood.

5. Avoiding Eye Contact

Directly staring at another dog is a threat or challenge in dog language. A dog who doesn’t want to fight will avoid eye contact to tell the other dog he is backing down. A dog may do this with a person it finds threatening, too. If the offender proceeds to mess with your dog’s boundaries, he may feel cornered and lash out.

What Causes Dog Aggression?

Unwitting people and other dogs often accidentally frighten dogs. This may be a result of poor socialization as a pup or trauma. It could also be that the other dog is bullying your dog or that a person is invading your dog’s personal space. Whatever causes your dog to become afraid or irritated can result in aggression.

Dogs may show aggression when they are being possessive. They can do this with toys, food, sleeping areas, or people. This type of aggression is called “resource guarding.” In the wild, dogs had to protect their resources to survive. So, they still try to do this in our homes today. You can train most dogs to relinquish resource guarding with some training and easy-to-learn tricks.

According to the ASPCA, if a dog is aggressive, one of the best ways to curb this behavior is to limit your dog’s exposure to triggers. Dogs with a history of aggression are at risk of exhibiting this behavior again.

You can also begin behavior modification with the guidance of a qualified professional, such as a certified trainer or dog behaviorist. They’ll rely on a system that rewards your dog for good behaviors with praise, treats, and toys.

You can prevent sexual aggression by having your dog spayed or neutered. If your dog exhibits resource guarding, you can try introducing an even more enticing item to the dog to get him to give up what he is guarding. Then, you can train your dog with a “drop it” to start the process of getting your dog to give up his prized possession.

Which Dog Breeds Are Prone to Aggression?

You may wonder if certain dog breeds are more aggressive by nature. Certain breeds have a reputation for being aggressive, but often, this is due to their perceived size. Many people perceive larger dogs as more aggressive because they can do more damage when they attack, but smaller dogs can be just as aggressive (ever seen an angry Chihuahua?).

Many times, aggression forms as a result of animal abuse or trauma. Also, a dog who grows up in a household with fewer resources may be more prone to resource guarding. Lack of socialization and training early on can also encourage aggression. Past abuse may also create reactive behaviors in dogs.

Any dog breed and any size of dog can develop aggression.

When you are observing multiple dogs, you will want to keep on the lookout for dog-on-dog aggression. Dogs warn other dogs they are becoming fearful or annoyed through body language and verbal cues. If the other dog doesn’t back down, this could lead to biting, fighting, and injury. Dogs can also be aggressive towards people.

Any dog breed can be aggressive, but most aggression is a result of fear, pain, or lack of training and resources. There are several ways you can work to curb your dog’s aggressive behaviors. If you need additional help, seek out a certified training specialist or a behaviorist for assistance.