Clients often complain that their dog chases children, joggers, bicyclists, and cars. What can I do to help them with this problem?

Chasing is part of the normal predatory sequence and play behavior for dogs. Therefore, all dogs on occasion may engage in aggressive or nonaggressive chasing behavior. However, a dog that aggressively chases people can create a serious and dangerous situation that should be addressed as territorial aggression, with or without fear, or as predatory behavior. Dogs often chase children as they play, but even playful chasing can be accompanied by jumping and nipping, which can be dangerous. In addition, chasing, even though it may not represent a serious behavior problem, still creates problems for owners and/or the target of the chasing. This article will discuss nonaggressive chasing behaviors.

Characterizing the Problem
Anecdotally, problem chasing behaviors are seen frequently in herding breeds, such as border collies, shelties, and Australian sheepdogs, and in various sight hounds. However, all breeds of dogs may engage in chasing behaviors. Chasing is self-reinforcing on two levels: First, regardless of whether it is a play or predatory behavior, it is fun or meets a biological need. Second, if dogs that chase to satisfy territorial defense are successful in causing the target to leave the territory, they have accomplished their objective. Chasing behind fences is also reinforced by removal of the target.

First Steps
First and foremost, the owner must control the dog and prevent the chasing behavior. This often means that the dog cannot be left outdoors unless it is with an adult and on a leash to prevent chasing, even behind fences. Some dogs that chase are extremely territorially aggressive and may injure people if they are able to get close to them. Even if the dog does not have aggressive intent, it is frightening to be chased by a dog, as the target often does not know the dog or its intent. When children are present and playing, the dog must be elsewhere if they chase children in that context. Dogs that chase and lunge on walks should not be walked until the owner has better control of the dog. All physical and interactive punishment must also be stopped-such techniques may actually increase emotional arousal, are usually ineffective in changing the behavior, and can cause fear and anxiety in the dog.

Treatment Protocol
Treatment focuses on increasing owner control (in many cases, using some type of head halter greatly increases owner control and diminishes chasing), teaching the dog how to relax, and desensitizing the dog to the stimuli that cause chasing. In addition to determining what stimuli elicit chasing, the following questions should be answered:
• At what distance does the dog focus on the target?
• When does it begin to track the target?
• When does chasing begin?
• At what point does the dog become uncontrollable?

Knowing how the stimulus gradient influences the response is essential. In most cases, when the stimulus is very intense and close, the dog is too emotionally aroused to learn anything new. Therefore, controlling the stimulus intensity is important to facilitate learning new responses.

Settle/Relax Exercises
Next, the dog is taught to settle or relax and focus on the owner so that he or she can hold the dog's attention for 30 to 60 seconds. This is usually done with the dog sitting and looking at the owner while the owner gives a verbal command, such as "Watch me" or "Look at me." Rewards, such as small tasty tidbits or play, help facilitate this task and should at first be offered consistently. This exercise should initially be practiced in various locations without distractions and then gradually in more demanding situations. As the dog learns to remain calm, rewards can be used intermittently.

Using the distance gradient established earlier, the dog is slowly exposed to the stimulus and rewarded for not chasing as well as for calm and settled behaviors. Initially, the stimulus might need to be far away to increase the dog's chances of remaining under control. As the dog begins to relax at the lower intensity, the stimulus can move closer, using desensitization to change the behavior. Between sessions, it is essential that the dog is not allowed to engage in chasing behaviors. The goal is for the dog to learn to relax in the presence of the stimulus. As the dog is rewarded for relaxed behavior, counterconditioning is taking place and it is hoped that the dog will become better able to calmly watch the owner and to sit or stand still as the stimulus passes by. Use of a stated phrase such as "Watch me" allows owners to redirect the dog's attention to them when the stimulus is present.

Playing Children
When the problem is directed toward children in the home as they play, owner control is especially necessary. A head collar and lead allow the dog to be present but under control so that it can be rewarded for not chasing. Children should learn to play appropriately with the dog using such games as fetch to avoid chasing and lunging responses.

In some cases, the dog may learn not to chase and can be trusted outdoors alone or behind a fence. If the dog exhibits any defensive territorial behaviors, it must always be supervised outdoors. When playing children are the targets, with diligence the dog can be taught not to enter into running and chasing or the behavior can be redirected to fetch games that are more controlled and less potentially injurious. However, there are some circumstances under which the dog must always be separated from the situation to keep everyone safe.

What to do
• When the dog is outdoors, establish control by using a leash and head collar
• Minimize opportunities for chasing by limiting walks or contact
• Determine which stimuli activate the behavior
• Establish a stimulus gradient
• Teach the dog how to "watch" or "focus" in calm surroundings
• Slowly expose the dog to the stimulus and reward it for good behavior