Why do dogs wag their tails?
Communication is more than just words. For humans it's all about shaking hands, waving, eye contact or body posture. The endless gestures and expressions we have to communicate with people is impressive and before twerking we could proudly say that wiggling our bums wasn't one of them. For dogs, communication is not just vocal either; they express themselves through their stance, eye contact and of course tail movement.
So how do we determine if our neighbour's dog is feeling happy or angry? Most commonly, we look for a wagging tail. A wag means happy and no wag means not happy, right? Wrong. A common misconception about tail wagging is that if a dog is wagging his tail, he's happy but studies have shown that tail wagging can also happen when a dog is feeling aggressive, threatened or stressed.
Before analysing a tail wag, it's important to understand how the position of the tail plays a part. However, please note that due to the variety of different dog breeds and their corresponding anatomical makeup, the natural stance of a pug's tail is going to be different to a greyhound and so forth.
High in the air.
This is a sign of confidence and usually dominance. One way a dog spreads their scent is through their anal glands. A high, wagging tail helps to spread more of their scent and show their authority in the pack.
Pointing straight out horizontally.
This may indicate that your dog is being cautious and/or feeling threatened and is likely to be aggressive.
Usually a sign of more submissive animals, a tail tucked between the legs is a sign of fear or anxiety. As mentioned, dogs release their scent through their anal sacs. If your dog is trying to hide or go unnoticed they will keep their tail low to prevent their scent from spreading.
This is usually halfway between horizontal pointing and tucked under however it will vary depending on breed. Your dog's neutral position, where their tail is not rigid, shows that they are relaxed and comfortable.
When it comes to tail wagging, studies show that positioning is more than just high or low; left and right also comes into play. A study published in 2013 tested 43 dogs and their responses to left or right tail wagging. Their behaviour and heart rate was monitored during and after exposure to the stimulus of a dog wagging its tail. Differences in heart rate and behaviours were documented for left wagging, right wagging or when the tail was held in a neutral, non wagging state.
Left wagging caused the participants to become stressed and alert. Left wagging is found to be a warning sign for dogs and usually indicates withdrawal or aggression.
When exposed to the right wagging stimulus, dogs were more relaxed. They were more likely to approach the other dog and reciprocate friendly behaviour.
A dog's tail is a very important communicative device and each angle has a different meaning. Dog's who have very small or docked tails may be hesitant when approaching other pets. As their tail is a tell tale for whether they are hostile or friendly, the lack thereof causes uncertainty in other dogs who may misinterpret their approach as threatening.
Communication cues such as tail wagging can help you to understand how your dog is feeling, and in turn avoid hostile situations. Next time you take Bailey to the dog park, have a look for the different tail types and see if you can identify the differences between confrontation and play.
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