My dog is friendly when off-leash, but when I put her on a leash she becomes aggressive towards other dogs. How can I change her behavior?

Is your dog friendly most of the time, but turns into a monster when you clip on the leash? There are many possible explanations, but animal behaviorist Petra Mertens believes it could be a sign of frustration. She says, “the dog would maybe normally approach or avoid or stand over to the side and that inability limits his expression and causes some frustration.”

Mertens says proper socialization as a puppy is the key to preventing leash aggression, but even learned behavior can be changed.

Pulling on the leash and speaking to the dog reinforces the unwanted behavior. So instead, Mertens recommends teaching alternative behavior, which takes patience and practice. You might need the help of a professional.

– Dr. Andrea Looney, DVM for the “Purina® Animal Instincts” Podcast Series

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