Why Is My Big Dog Afraid Of Small Dogs?

You know the saying "his bark is worse than his bite"? It was basically coined to describe terrifying, tiny, yappy dogs. How often have we seen this situation: Two dogs are on their walks, heading toward each other. One of them is big — a Lab, a husky, something substantial — the other is tiny enough to be carried in a purse — a Yorkie, a Maltese, a Chihuahua. As they approach, they notice each other and do the very quick work of sizing each other up. When the moment comes and their paths actually cross, the tiny dog starts barking wildly and lunging at the big dog, who inexplicably recoils in fear.

Dogs playing in the autumn forest
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It seems nonsensical. The big dog could swallow the little dog whole and, yet, the little dog is the one commanding all of the power in the exchange. Why is it that big dogs are sometimes afraid of little dogs? Let's dig in.

Why do small dogs act aggressively toward big dogs?

In order to understand why big dogs are sometimes afraid of little dogs, we have to first unpack what possesses tiny pups from snapping at unaggressive larger dogs in the first place. Little guys can often develop what dog trainers refer to as small dog syndrome, and it's kind of our fault as dog owners. The behavior itself isn't unique to tiny dogs; we just allow them to get away with it a lot more often than their bigger cousins.

Here's how it works: When a big dog barks or jumps at people or other dogs, we immediately correct them. No owner of a Great Dane or mastiff is okay with their dog behaving this way; it scares other people and causes a whole thing. When smaller dogs behave the same way, however, we're more likely to let it slide. After all, it's not like the tiny Teacup Yorkie is going to really hurt anyone. We laugh. We apologize and pick the dog up. We enable the behavior instead of correcting it.

Which leads to small dog syndrome, a condition in which smaller dogs habitually bark, charge, and otherwise react aggressively towards people and other dogs. It can be especially common when the smaller dog is afraid. It might not even be that the small dog is trying to scare the larger dog in this situation. It could be that tiny pups have been conditioned to know that this behavior leads to mom picking him up and walking away quickly, so he throws a fit like a toddler who is tired of running errands and knows that crying will make mom take him home.

Screaming Chihuahua
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Why do big dogs sometimes seem afraid of tiny dogs?

Big dogs are reacting in a totally normal, logical way when confronted with aggression. We know that the little dog isn't a real threat, but for a big dog who isn't prone to aggression, seeing that kind of behavior from any other animal, even one who is smaller than him, is downright scary.

Professional dog trainer Marta Young explained on Quora that the big dog has no way of knowing just how aggressive the small dog is or what its intentions might be. As far as Big Scaredy Dog knows, the little dog might actually want to kill him, and what looks like fear could be a totally rational attempt to avoid a fight, even if it's one he would ultimately win.

"If a tiny aggressive man started shouting at you, waving his arms wildly and threatening to hit you, what would your likely reaction be?" Young wrote. "To fight him, or to back away?"

Chihuahua on Great Dane's back
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Okay, but what if my big dog is afraid of a small dog who isn't barking or acting aggressive?

If you notice that your big dog is consistently fearful around smaller pups, even if they aren't behaving aggressively toward him, you should look to his past. If you've had him since he was a puppy, can you recall a traumatic experience he might associate with small dogs? If he's a rescue, consider the possibility that he's experienced some small dog-related trauma of which you are unaware. Most often, past trauma is at the root of recurring fears that seem to have no "rational" trigger for dogs.