Understanding Aggressive Behavior in Dogs

Article taken from Dumb Friends League, ddfl.org

The word “aggression” can refer to a range of behaviors from barking and growling, snarling and snapping, to biting and attacking. Threats of aggression are one way dogs have of communicating and are often displayed as a means of avoiding outright aggression. However, a threat (growling or snapping) may escalate to outright aggression (biting) in any given situation.

There are many different reasons for aggression. Because aggression is so complex, and because the potential consequences are so serious, we recommend that you get professional in-home help from an animal behavior specialist if your dog is displaying aggressive behavior. Our Animal Behavior Helpline can’t assist you with aggressive behavior problems. (See our handout: “When The Behavior Helpline Can’t Help.”)

Types of Aggression

Fear-Motivated Aggression: Fear-motivated aggression is a defensive reaction and occurs when a dog believes he is in danger of being harmed. It is the dog’s perception of the situation, not your intent, that determines his response. For example, you may raise your arm to throw a ball, but if your dog perceives this to be a threat, he may bite you to protect himself from being hit.

Protective, Territorial And Possessive Aggression: Protective, territorial and possessive aggression are all similar, and
involve the defense of valuable resources.
– Territorial aggression is usually associated with defense of property or space. Be aware that your dog’s sense of territory may extend well past the boundaries of his yard. For example, if you walk your dog regularly around the neighborhood, to him, his territory may be the entire block.

– Protective aggression usually refers to aggression directed toward people or animals that a dog perceives as threats to his family or pack. One specific type of protective aggression is maternal aggression, where mother dogs become protective of their puppies.

– Dogs that are possessively aggressive may defend their food, toys or other valued objects, such as tissues or food scraps stolen from the trash.

Social Aggression: Dogs are social animals and view their human families as their social groups. Based on the outcomes of social interactions among group members, a social hierarchy is established. This hierarchy determines each member’s access to valued things (food, toys, resting places, etc.) and minimizes the need for conflict. Social aggression may be directed at people or at other animals.

The most common reason for dogs in the same family to fight with each other is instability in the social hierarchy. Social aggression may occur if there is a challenge to a higher ranking dog’s social status or to his control of a social interaction. (See our handout: “Canine Rivalry.”)

Because people don’t always understand canine communication, you, a guest or child may inadvertently challenge your dog’s social position. If the dog perceives himself as higher ranking than the challenger, he may attempt to assert his status through aggressive displays. A socially aggressive dog may growl if he is disturbed when resting or sleeping, or if he is asked to give up a favorite spot, such as the couch or the bed. Physical restraint, even when done in a friendly manner, like hugging, may also cause your dog to respond aggressively. Reaching for
your dog’s collar, trimming his nails, or even bending or reaching over him could also be interpreted as a challenge.

A socially aggressive dog is often described as a “Jekyll and Hyde,” because he can be very friendly when not challenged.

Social aggression is complex and not best resolved through physical force. Practicing “Nothing in Life is Free” (see our handout on this technique) is a good way to ensure a stable social hierarchy with humans in control. Avoid any professional that recommends techniques that involve instilling fear or respect through physical means, such as alpha rolls or scruff shakes, as these may provoke aggression in your dog.
Frustration Aggression: Some dogs, if restrained when aroused or excited, will be aggressive toward the persons restraining them. A dog being held back by the collar may turn and bite the hand on the collar. A related type of aggression is barrier frustration and manifests when dogs are in a cage, crate or car. Aggression in these circumstances, however, may also be defensive and/or territorial. Redirected Aggression is a type of frustration aggression that is relatively common. If a dog is aroused into an aggressive response by a person or animal that he
is prevented from attacking, he may redirect this aggression onto someone nearby. Owners are often bitten when they try to intervene in a fight between two family dogs. Another example occurs when two family dogs become excited, bark and growl in response to another dog passing by the yard. The two dogs, confined behind a fence, may turn and attack each other because the fence prevents them from getting to the intruder.

Pain-elicited Aggression: An otherwise friendly and social dog may also bite or snap if touched when he is in pain. You may be treating him or attempting to help him, but he perceives any touch from you as potentially painful and snaps or bites to make you go away. If you are working with a dog in pain, it is a good precaution to muzzle the dog. Some training tools that inflict pain, such as prong collars, may provoke a dog to pain-elicited aggression. We do not recommend using tools that cause pain or fear.

Predation is usually considered to be a unique kind of aggressive behavior, because it is motivated by the intent to
obtain food and not primarily by the intent to harm or intimidate.

Individual Variation
Dogs differ in their likelihood to show aggressive behavior in any particular situation. Some dogs tend to respond aggressively with little stimulation. Others may be subjected to all kinds of threatening stimuli and never attempt to bite. The difference in this threshold at which a dog displays aggressive behavior is influenced by both environmental and genetic factors. If this threshold is low, a dog will be more likely to bite. Raising the threshold makes a dog less likely to respond aggressively. This threshold can be raised using behavior modification techniques. How easily the threshold can be changed is influenced by the dog’s gender, age, breed, general temperament, and by whether the appropriate behavior modification techniques are chosen and correctly implemented.

Working with aggressive dogs can be potentially dangerous, and should be done only by, or under the guidance of, an experienced animal behavior professional who understands animal learning theory and behavior.

What You Can Do
– First, check with your veterinarian to rule out medical causes for the aggressive behavior.
– Spay or neuter your dog. Intact males are more likely to display social, territorial and protective aggressive behavior.
– Seek professional help. An aggression problem will not go away by itself. Working with aggression problems requires in-home help from an animal behavior specialist.
– Take precautions. Your first priority is to keep everyone safe. Supervise, confine and/or restrict your dog’s activities until you can obtain professional help. You are liable for your dog’s behavior. If you must take your dog out in public, consider a cage-type muzzle as a temporary precaution, and keep in mind that some dogs can remove the muzzle.
– Avoid exposing your dog to situations where he is more likely to show aggression. You may need to keep him confined to a safe room and limit his contact with people.
– If your dog is possessive of food, treats or a certain place, don’t allow him access to those items. In an emergency, bribe him with something better than what he has. For example, if he steals your shoe, trade him the shoe for a piece of chicken.

What Not To Do
– Punishment will not help. It will, in fact, make the problem worse. If the aggression is motivated by fear, punishment will make your dog more fearful and therefore more aggressive. Attempting to punish or physically dominate a socially aggressive dog may cause him to escalate his behavior. This is likely to result in a bite or a severe attack. Punishing territorial, possessive or protective aggression is likely to elicit additional defensive aggression.
– Do not encourage aggressive behavior. When dogs are encouraged to “go get ’em” or to bark and dash about in response to outside noises or at the approach of a person, territorial and protective aggressive behavior may be the result.

Deciding Whether to Work with Your Aggressive Dog
Working with an aggressive dog requires resources—time, money and training skills. It also involves risk to you as the party responsible for your dog’s actions and to others who might be injured. Deciding whether to work with a dog with aggression issues is a difficult decision. You may wish to consider the following factors in making your decision:
Severity of the aggression: Dogs that have only growled, snarled, or air snapped (making no contact) are safer to live and work with than dogs that bite. However, these displays of aggression may escalate if the problem is untreated or treated incorrectly. Once a dog has bitten, he is a known risk and may be an insurance liability.

Warning signs: Dogs that give warnings before they bite—tensing, growling, baring teeth—allow people and other animals to retreat; dogs that bite with little or no warning are more dangerous.

Targets and triggers: If the trigger for the aggression is easily avoided, treating the behavior may be somewhat less risky. For example, if a dog is fearful of children and responds with defensive aggression, management of the problem would be easier for a childless couple who had few visiting children than for a family that had children or frequent visiting children.

Duration of the problem and reinforcement history: The longer the behavior has been going on and the extent to which the dog has been successfully practicing the behavior, the harder it can be to resolve it through behavior modification. For example, if the dog that is fearful of children has been successfully scaring them off for months or years through displays of aggression, it will take more work to resolve this behavior.

Ease of motivating your dog: Treating an aggression problem involves working with a qualified professional. Behavior modification for aggression should focus on rewarding good behavior. Rewards can include food, play and attention. Modification is likely to be more successful with dogs that enjoy these rewards. Dogs that are not motivated by these common rewards are more challenging.

Your ability to manage the risk of an incident: While you work on behavior modification, you will need to manage the dog and his environment to avoid an aggressive incident. This means the dog needs to be safely confined at all times and his contact with potential triggers and targets kept to a minimum. If you cannot implement and enforce restrictions on the dog’s activities and interactions, you are at greater risk of having an aggressive incident occur.

Your willingness and ability to commit resources to resolving the problem: Behavior modification will require daily training sessions, as well as sessions with a professional. If you do not have the time or money to do this, the chances that the problem will be resolved are slim.

If you decide that you cannot work with your dog’s aggression issues, you may want to consider relinquishing him to a shelter. Rehoming the dog with someone that is better equipped to manage and/or modify the behavior may also be an option, but please be honest about the aggression issues with anyone who is taking the dog. A person who is unaware of the dog’s problems could be injured by him, and an aggressive dog may be abused, abandoned or neglected as a result of his behavior.