Dog's aggression to visitors must be managed for safety

Q. My dog always barks at the mailman. This behavior has gotten more and more harsh, and I am concerned for everyone who approaches the house.

-Dane Leintz, Oak Brook

A. While this is a relatively typical behavior, it should be taken very seriously because it is a safety issue. Understanding your dog and knowing his or her triggers are essential.

There are two issues that you pose. First, is the fact that your dog barks at the mailman or uniformed people approaching your house. The trigger for your dog's behavior is invasion of territory, potentially exacerbated by the uniform, which is scary to some dogs.

The dog barks and the letter carrier goes away. To a dog, this is a "win." The outcome reinforces that barking makes the postal worker go away.

Intervention from you is key. A reaction that is unfavorable to your dog from you will help your dog realize the behavior is unacceptable. If you work full time and cannot be home consistently, then consider possibly enclosing your dog in an out-of-the-way part of the house to alleviate the behavior.

Next, now your dog expects everyone to retreat when he or she barks at the door, which may be the cause of the escalating aggressive behavior.

When friends arrive at the door, your dog does not understand why everyone does not leave when he or she barks. So the dog barks more in an attempt to get the positive outcome the dog is seeking (that the intruders will go away).

Remember that those coming to your house expect to be safe. If you have someone only visiting once - like a carpet installer, etc. - put your dog away. When your friends frequent your home, you may still want to remove the dog initially from the situation when friends enter and integrate your pet after everyone is situated in the house.

It is important to understand that aggression is managed, but after ingrained, is rarely cured or completely gone. So understanding the triggers, and when to remove your dog from situations when strained, is the goal. Be realistic about what your dog can and cannot handle. A realistic dog owner is a happy dog owner.

• Kerry Vinkler is director of DuPage County Animal Care and Control. To submit a question, e-mail animalcontrol@Dupageco.org; mail to 120 N. County Farm Road, Wheaton, IL 60187; visit dupageco.org/animalcontrol; or call (630) 407-2800.