6 Major Signs of dog aggression

Dog aggression is one such wild behavior and it should not be ignored. So have a glance at these six major signs of dog aggression and use a positive reinforcement to train good behavior.

Mouthing, without biting down hard: The mouthing of an aggressive dog is not to be confused with puppies play biting. Think of it instead as a dog shoving or challenging. This is a way in which a dog may size up a person and test if they will tolerate rude behavior. A similar conduct is found in herding dogs. I have had numerous clients with GSDs say their dog mouths and charge visitors when they get up to leave. That behavior is part herding instinct, combined with challenging the person.


Mouthing: The play bite on the jugular is in typical prey-kill instinct. This is a hard wired instinctive behavior which in this instance is all play. At times some dogs get overwhelmed and consider the play as an attack.

Muzzle punch: I’m not talking about accidental contact, rather a harsh muzzle shove/poke with a purpose. This is a rude push with the dog challenging and trying to control you or another dog. Depending on the dog, I would consider repeating whatever one was doing just before the muzzle punch occurred, gradually looking for the dog to lessen its undesired behavior through reward. The reason to recreate the event is so you can desensitize the canine to the triggering event.

Growl, usually paired with a lip curl: One of the easy cues to pick up on is canine growling. The dog is using its language to say, “Stop what you are doing.” Likely, the dog is feeling its personal bubble being invaded or is protecting a resource. The resource could be a possession, such as food, toys, or in extreme cases, a person. It’s important not to pressure a stressed dog too much; however, not working through it will never make the behavior go away. If the pet learns it can get people or dogs to back off by growling and curling the lip, it will continue to do it.


Lip curl- The Dachshund is lip curling because it didn’t like the approach from the other dog. The dachshund being on leash doesn’t help the situation because it is so tight, watch how the owner is holding the leash. Remember also, that everything runs down the leash.

Showing teeth: Some dogs show teeth before growling, while others will curl the lip, show teeth and growl. You may also observe that the eyes are wide and dilated. This is a dog trying to avoid conflict by warning, so be sure to honor that in some way, i.e. consider the environment and confirm if the dog’s reaction is valid.

Snarl: This is a growl paired with baring teeth, which is saying that things are beginning to get more serious. The dog is triggered here for sure and is likely willing to bite, moving forward. You must take note of what caused the dog to react this way and train the issue. Essentially, change the dog’s frame of mind. If the dog is protecting its food and doesn’t want anyone coming close, change the dog’s thinking to expect that when you come close, you are going to add something of higher value to the food bowl.


Snarl- This is what a snarl can look like when dogs are playing. This play is borderline too rough. Look at the dog on the far left, he looks concerned, it is showing caution.

Snap: Believe it or not, a snap is just a warning bite. The dog is attempting to signal it’s insecurity in a more obvious way. With a snap, the dog does not intend to bite and latch on, however, if the pressure continues, it can go from snap to bite, quickly. A good example is when a dog is cornered. I myself Ryan Matthews, the dog trainer specialists in Orange County, have found that dogs lacking confidence, with aggressive tendencies, will snap at humans when they turn their back. It’s because the dog didn’t have enough courage to do it when the human was in the more intimidating posture of eye to eye contact. The lesson here is if a canine has any sign of aggression; never turn your back on them. Additionally, it is important to never corner a fearful canine, but ensure there is an exit for them if they get too stressed.

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