Your dog or puppy may gain unwanted habits overtime due to their exposure to other k9’s. This is natural and you should be prepared to be ready to expect new behavioral traits when walking your dog in new places like the park or when taking a different route down a new a road.
If your dog starts to bark at other dogs when taking him/her out for walk on a leash first thing you shouldn’t do is no shaking of pennies in a can, or forcing the dog into a submissive position, or any of that.
It is most likely your dog has what is known as fear-aggression. It’s different from “regular” aggression because, obviously, of fear. The last thing you want to do is scare your dog even more, or associate other dogs with even more negative reactions.
When you go for walks, bring a small bag of treats with you in your pocket. When you see another dog coming, RELAX. Don’t tighten your hold on the leash, shorten the leash or even act nervous. Your dog will be able to feel you tense up. I know you’re going to be worried thinking “oh no, here it comes” but don’t even think about it. Roll your shoulders back and forth, take a deep breath.
When your dog DETECTS the other dog (not before, and not after she has gone into the barking fit) this is when you must take action. Get her attention as quickly as you can. Basically, you need to break her mind off that “mental state” where she is fixated on the other dog. You can try getting her attention by waving the treats in her face, by making high-pitched noises and jumping up and down, by saying her name, or anything that works. (You’ll look pretty stupid, but just do whatever you’re prepared to do.)
The MINUTE she looks to you, give her the treat, pet and praise. Then, immediately turn and walk away from the other dog. Don’t bring her any closer.
Gradually, you will be able to decrease the distance from which the dog is to you before your terrier starts going nuts. I have been working with a fear-aggressive dog in the last few months. Two months ago, she would start barking her head off a 50 metres away from the dog. Now, she is okay with dogs as long as they are on the other side of the street. Soon she will be able to walk right past dogs on the same side of the street with no trouble at all.