Aggressive Behavior

Question
Hi, I have a 23 month old neutered male Boxer named General and when out walking, if we meet any one and he is on the lead. To begin with he is pleased to see people, then with no warning begins to growl yet his tail still wags. He acts as though he is trying to intimidate them.  Also this happens when we are in the truck and he is sitting in the back seat with the window down and people come up to talk to him and he is tickled to see him but then will growl.....I understand that this (in the truck) is "his" space and that's why he does it in the truck.  I don't think he would ever bite anyone, but we don't take that chance.
I understand this is learned behaviour however unsure where it came from or how to stop it. Please help.

I thank you very much and will post rating when available.
Nancy  

Answer
Hello Nancy,

This seems to be a common Boxer problem.

Unfortunately, it actually all starts when they are little puppies.

Although we don't realize it at the time, when they are puppies, they are behaving that way then, and we chalk it up to "puppy play" and "cute." But, what is actually happening is, we are "giving permission" to the young, impressionable puppy, to growl at people and be "territorial."

Since the nubby tail (supposing it is docked) is wagging, which is a sign of playfulness and excitement, he wants to play, is excited to see people and anxious to play- yet, he is "on-guard" and being "territorial" and "protective" of family (you).

It's a mixed emotion with his imagined duty to protect and distrust.

To modify his growling behavior, try a few things.

On a leash walking, allow the leash to be fairly loose on your grip- relaxed. When he begins the growling, tighten the leash with shortening it in your grip, and stopping. I would turn him pointed away from the people/dogs (cause of his growling) and order him to sit.

Do this each time, as to turn him and distract him away from the source. Continue on walking, and next time, do it again. Repeat over and over. It will take more time than usual because of the stopping delays, but well worth the conditioning.

Soon, he won't notice other people and dogs.

You might try the whistle with this: blow the whistle as you tighten and shorten the leash, turning him away from the source, and ordering him to sit.

Let me know how this woks. (and take the whistle with you in your truck for those times).