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Aggression is one of the most common reasons pet owners seek professional help. But what really is aggression? Aggression is typically viewed as any threat to harm an individual, whether this individual is human or another animal. There are many different forms of aggression, and it is important to determine the cause in order to appropriately deal with the issue at hand. Aggression can be due to guarding territory or protecting a family member, resource guarding, fear, frustration, prey drive, and/or pain.

Reactivity: Reactivity is commonly confused with aggression. Dogs that are reactive are those that overreact to certain things or situations. Genetics, lack of proper socialization, or a combination of the two can cause reactivity, and fear is typically the driving force. Reactive dogs may have certain triggers, such as men with beards or hats, small children, or situations when the dog feels trapped by being on a leash.

Fight or Flight: Fear is the most common cause for aggression. Normally when a dog is scared, it chooses to run from what it’s afraid of. In situations where a dog is trapped and cannot flee from the inciting cause, he will decide to fight to preserve himself. Fearful dogs may not give any additional warnings other than their body language. The bites themselves are typically quick snaps and may occur when the person is leaving and has his back turned.
border collie

There are many behaviors that look a lot like aggression but are not.

Listed below are some of the behaviors commonly confused with aggression:

Mouthing/Nipping Puppies – Puppies interact with their world through their mouth. When puppies play, either with other dogs or with their owners, they can become mouthy. Commonly they may become over-stimulated and nip harder than they should when playing. This nipping is not coming from a puppy that is being aggressive, but rather he is just having too much fun playing and needs a break.

Rough Play – Dog-to-dog play is a normal part of canine interaction. Dog play is mock fighting. Puppies learn how to do this appropriately from their peers. Dog play can become intense, get loud, and appear aggressive, but as long as both dogs are having fun and respecting their body language, it can be a great activity for socialization and exercise.

Resource Guarding – Dogs will tend to guard things that they believe hold great worth. These items can be toys, food, bones, sleeping areas, and even people. This tendency comes from the fact that our dogs descended from ancestors that were wild and had to protect their resources in order to survive. Teaching dogs behaviors such as “leave it” and “out” can help curb this behavior. Another good way to deal with resource guarding is to trade with your dog, exchanging the forbidden object that he is guarding for a treat.

Leash Reactivity – Leash-reactive dogs tend to growl, bark, and/or lunge toward things that make them nervous or fearful. These triggers may be other dogs and/or people and can be narrowed to specifics such as children, men, people wearing hats, or male/female dogs. Dogs that display these behaviors are not acting aggressive, they are trying to prevent a fight. They are trying to make the threat go away or increase the distance between themselves and the threat. If a reactive dog approaches you, the best thing you can do is give him space. Do not approach in an attempt to greet him. The owner is likely trying to train through the behavior, and by keeping your distance you will help in this training.

Body Language

Since dogs cannot talk, they must rely on their body language to tell other dogs and humans how they are feeling about different situations. Below are some common body language signals that everyone who interacts with dogs should know:

Signs of a Happy Dog:

Signs of anxiety:

  • Yawning when not tired
  • Lip licking
  • Sudden scratching
  • Sniffing

Signs of arousal:

  • Ears forward, mouth closed
  • Eyes intense
  • Body forward and tense
  • Tail high and slowly wagging

Signs prior to a bite:

  • Signs of anxiety or arousal
  • Direct eye contact
  • Showing whites of eyes
  • Growling
  • Showing teeth

If you believe your dog is truly aggressive, then it is best to seek professional help. You can start by asking your veterinarian for a reference for a behaviorist in your area. Other resources are the International Association of Animal Behavior Consultants (IAABC); the Certification Council for Professional Dog Trainers (CCPDT); and the Association of Professional Dog Trainers (APDT).

For more training advice, check out the video below.
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