Aggression is usually rare in puppies — but some dogs can start displaying reactivity at a young age. If you're worried about puppy leash aggression or think your family's new addition might be leash reactive, you've come to the right place.
Here are some key things to know to help your pup grow up into a happy, confident, well-behaved dog!
Everyone’s favorite answer here: It depends.
"Leash aggression" and "leash reactivity" are often used interchangeably. They terms can have slightly different nuances in meaning, though, depending on who exactly you’re talking to:
Both refer to undesirable behaviors (like barking, growling, lunging, whining and pulling) your puppy might show when they encounter a specific trigger (like other pets, strangers, bikes, or cars) on leash — so in this article we’ll treat both terms the same way.
More often than not, leash reactivity is caused by one of two major F-words: Fear and Frustration.
Typically, a dog who is being reactive on their leash has one of two goals in mind. They either want to get away from something they’ve seen in their surrounding environment (fear) or they want to get closer to something (frustration).
In fear-based leash reactivity, your dog’s fight or flight response has been triggered and — no matter which instinct they’re inclined to follow — they feel trapped by their leash.
Even a dog who instinctively wants to run from a perceived threat will often fallback on seemingly aggressive behavior, like barking and growling, if their leash makes fleeing the scene impossible. (Think of this like the classic "fight or flight" response we hear about in almost all animals. If we've removed the flight option by holding our dogs still on a leash, they're left with fight as a go-to fearful response.)
Dogs experiencing fear-based leash reactivity will often seem even more aggressive than their more excitable frustration-based counterparts. Anyone with a tiny dog who becomes a barking machine at the sight of any bigger dog on walks knows this all too well!
Frustration-based leash reactivity stems from a dog’s unmet desires. This could be anything from the desire to play with another dog on a walk to a desire to run up and say hi to every human they see to a deeply-ingrained need to chase all squirrels, birds, and other small creatures.
Just because a dog wants to do something, however, doesn’t mean they should — take the all-too-common doggy desire to dart into traffic and chase cars, for example. While using a leash is a fabulous way to manage these situations, it's inevitable that some undesirable replacement behaviors might bubble up when we restrict our dogs from following their natural urges.
Leash reactivity can develop at various ages in dogs. There isn't a specific turning point that always applies! Certain factors may contribute to the development of leash reactivity at different life stages, though.
Here are some things to consider:
Distinguishing between leash aggression and excitable behavior in a puppy can be challenging. Both may involve barking, pulling on the leash, or other energetic reactions out on your walks. You don’t want to panic about your dog’s long-term behavior if it’s just a normal phase — but you also want to take any signs of reactivity you see seriously so that you can start helping your pup right away.
Here are some components to think about when trying to determine whether your puppy might be on their way to becoming a leash-aggressive dog or is simply being excitable:
Leash reactivity in a puppy doesn't necessarily predict that the behavior will be worse in adulthood. A puppy's behavior is still highly malleable! Training interventions can be particularly effective at a young age.
That said, a very young dog displaying leash aggression might suggest that the behavior is at least in part genetic, meaning it could be more difficult to completely address. Regardless of your individual dog’s history and predispositions, though, the most important thing is to address the reactivity as early as you can, starting with a comprehensive exam by a veterinary professiona.
The right, humane training methods and proper socialization experiences can go a long way!
There are countless great resources for how to live with and train a reactive dog! Here are a few that we like.
We have an entire blog category devoted to dog reactivity and related problem or unwanted behaviors. One of our primary goals is to be a welcoming community for reactive dogs — that’s why we have intentional rules (like gaps between arrivals and transparency about other animals within view) to keep all Sniffpots safe.
Here are a few specific articles:
Good luck, and remember: you’re not alone. When in doubt, get in touch with a professional force free trainer or veterinary behaviorist you trust. (They should be able to help you rule out medical conditions, choose the right training tools, implement counter - conditioning, and teach you about other behavioral therapy).
And know you can always bring your dog to a Sniffspot for some playtime!
There is so much misinformation out there, and we want to make sure we only provide the highest quality content to our community. We have our articles reviewed by qualified force free trainers.
This is the trainer that reviewed this article:
M.Ed. Humane Education
Karen Pryor Academy Certified Training Partner
Certified Tellington TTouch and TTEAM Practitioner
Sniffspot Research 2023, n = 4,092
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