Dog’s use their tails as an important avenue of communication, both with other dogs and with us humans. That’s one reason why some countries have banned tail docking, as it literally “cuts off” one of the primary ways dogs use to communicate.
You may have heard of someone, or even experienced yourself, a situation in which they saw a dog “wagging its tail” and just assumed the dog was friendly, only to find out that was definitely not the case!
Dogs who are standing their ground or threatening something or someone will hold their tails high and stiff (called “flagging”) and wag it slowly back and forth. The hair on the tail may also be bristled. This is not a dog that is feeling friendly but is a clear offensive signal.
A dog who is feeling friendly and outgoing will use his whole back end, including the tail, to communicate this. Some studies even show when the tag wags more to the right it involves more positive feelings that one wagging more to the left.
Then there is the tail position that signifies the dog is expressing interest. The tail hairs are smooth and not bristled and it will likely be held out horizontally with a slight side to side wagging motion.
A dog who presents with a lowered tail may be communicating a couple of different things. Sometimes this represents a dog who is just really very relaxed. But it can also signify a fearful or frightened dog. Don’t mistake this for a submissive posture as it is not, and if the dog is pressured, he may lash out.
A submissive tail is one that is clamped down tightly between the rear legs. This makes sense because this prevents other dogs from sniffing his genital area, as this helps to identify him to other dogs.
Spend some time watching the tail positions of your dog and other dogs. It’s fun to develop a sense of how important a dog’s tail is in communication.