5 min read


Why Dogs Wag Their Tails



5 min read


Why Dogs Wag Their Tails




For the sake of clarity, let’s refer to your lovable pooch as Roxy. If you feel the need, you may insert, Sparky, Lulu, Spud, or any other name you see fit. Roxy is a tail wagger, you love her to pieces, but she is always wagging that thing. Although you know this behavior is normal, you can’t always decipher why she is wagging her tail. You recognize that Roxy’s tail sometimes seems to be wagging more to one side than the other, sometimes the speed is quick and sometimes slow, sometimes her tail is high and sometimes it is low. You don’t speak dog, so you are unsure what these wags mean. Believe it or not, there are specific reasons for why and how your beloved Roxy wags her tail. 

The Root of the Behavior

According to experts, dogs wag their tails to communicate and interact. But perhaps the question we should really be asking is how does your dog’s tail wag? And what do these types of wags actually mean? Lisa Radosta, owner of Veterinary Behavioral Science in Florida, previously stated, “A tail wag means that the dog is open to interaction, not that the dog is friendly.” She also emphasizes the importance of observing how the tail wags in order to provide clues about your dog’s emotions. So back to Roxy. You want to know what your Roxy is trying to say. In order to do this, let’s examine what the different types of tail wags actually mean. According to well-known dog expert Cesar Millan, if Roxy’s tail is wagging side-to-side, you should also note the more prevalent side of the wag and how fast it’s moving. If it is moving more to the right, this can be interpreted as a sign of excitement, but if it’s moving to the left, it should be interpreted negatively, and Roxy may be panicked or anxiety-ridden. 

The reason for this all comes back to the brain. In both humans and animals, the left-side of the brain is associated with positive behaviors and the right side is associated with negative behaviors. To make it a bit confusing, each side of the brain controls the opposite side of the body. That’s why when Roxy’s irritated, her right side of the brain is more active, but her tail wags more to the left. Hopefully, your hands are not tied up in knots and you don't have a headache after reading this. Neuroscientist Giorgio Vallortigara of the University of Trento in Italy, actually led studies on this phenomenon. His results were published in The Journal of Current Biology. He observed various dogs watching a video of another dog wagging his tail to the left and then the right. He then gathered information, such as heart rate and video analysis-based on the dog’s reactions. 

Vallortigara observed that the dogs viewing wagged tails to the right tended to be more relaxed while the dogs viewing wagged tails to the left tended to become agitated. The direction in which your dog's tail wags up or down also plays an integral role in your dog’s demeanor. A dog with a tail up high tends to be cocky and dominant, while a dog with a tail low is most-likely nervous and/or scared. Let us not forget to examine the speed of a dog’s wag. It’s pretty similar to humans. If you move like a sloth, you probably are not the most energetic of the bunch, but if you stride quickly, you probably have the energy of a rock star. Of course, your energy can change during different times of the day. This is the same for dogs. Think about Roxy. It’s morning, she’s ready for her first meal. She’s well-rested and that tail is wagging so fast that she could whip you with it. The speed shows her high level of energy. 

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Encouraging the Behavior

Without a doubt, your dog is going to wag her tail, and instead of condemning it, you should observe how your dog’s tail wags, and use these wags as clues for communicating with your dog. For example, think about the following scenarios: You are walking your sweet, little Roxy down the street. If you run into another a dog, which seems to inevitably happen on those morning walks, you can observe Roxy’s tail as well as the other dog’s. This will allow you to either allow Roxy to interact or book it in the other direction. You just arrived to the vet’s office, uh-oh, Roxy knows, she’s been pricked and prodded here before. Her tail is wagging downward, and is between her legs; you realize this is her instinctual way of freaking out. 

Later that day, you take Roxy to a dog park. She plays for hours and then on the way home, her wag slows. Newsflash: she is tired. Being able to recognize the significance of your precious Roxy’s wag is providing you with insightful views of her behavior. Fast forward to that evening at home. You and Roxy are sharing a nice evening until your cat Snowball comes around. Now Roxy’s tail is up high, and she is letting Snowball know that her space should not be messed with. Roxy is now expressing her dominance. See, it’s all about the tail, and you are, indeed, picking up on her communication.

Other Solutions and Considerations

Could tail wagging be an issue? Well, usually not, but sometimes yes. If your dog is known for ferociously wagging her tail, she actually could injure it and irritate the tail more by licking it, etc. Dogs will be dogs. Excessive wagging could also be a sign of anxiety and high energy that could start to annoy you and be problematic for others. If this is the case, behavioral therapy could be necessary, and the goal would be to work on calming your dog down so her interactions with you and others are not so high-strung. Also, as stated earlier, a dog’s wag is not always a sign of something good, and sometimes people misinterpret a wagging tail as an invitation to approach your Roxy—even if she is in a bad mood. If you are able to identify the type of wag and Roxy’s state-of-mind, you can let others know if it is okay to pet her or stay away. This certainly could be a handy trick for pet owners.


For the most part, Roxy’s tail wagging is no need for concern, but rather a way to explore your dog’s emotions, temperament, and level of agitation. Remember to observe how Roxy’s tail wags: more to the right, more to the left, up high, down low, quickly, slowly? So, when Roxy starts-a-wagging, take a paws and observe the wag. If you do this, you are one step closer to speaking dog, and this is a talent that Roxy will think is barktastic!

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