German Shepherd barks at other dogs only while on leash

Hi Al,

This is what's called "Leash Aggression". There are two types:

1) is usually by playful dogs. They want to get close to other dogs to sniff/play but because of the leash they cannot. Owners tend to pull the leash trying to keep the dog away from other dogs thinking his dog might attack them. That would make things even worse since his frustration builds up and makes him act more aggressive.

2) is shown by under-socialized dogs. When they are leashed there is no way for them to run away in case the other dogs get close to them so they get in the protective mode.

I think your dog sounds more like 1). Either case what you need to do is to make him "Sit and Stay" and calm him down. If your dog is friendly and playful, ask the other dogs' owners if their dogs are friendly or not. If they are, explain your dog's issue and see if it's OK to let him close to their dogs, or walk along side by side with their dogs.

Make sure you are not tense but you are well prepared to control your dog if he starts getting into a fight. You should look at his body language, such as his tail position, his hackles, etc.

This needs to be addressed as soon as possible since this aggression gets only worse if you keep pulling your leash to avoiding the encounters, especially protective breeds like yours.