Why Do Dogs Wag Their Tails?

Dogs wag their tails as a means of communication but it’s not an on or off switch. A tail wag can mean very different things, depending on the rest of their body language. Tail wagging is an instinctive behaviour that develops between the ages of 3 and 4 weeks old. Puppies develop the behaviour just in time to start requesting milk from their mother, around when their mum might be spending a little more time away from them. They use their tail to request feeding and to happily greet their mum, which then develops into a greeting for us.

What starts as an instinct is then refined by the reaction they get. A happy, wiggly puppy will almost always receive a pleasant reaction from both dogs and humans alike. It is important though to differentiate a silly and happy wagging tail with their other behavioural wags. The positioning of the tail and speed of their wag can also show signs of them feeling anxious or threatened – it’s dependent on the situation they’re in.

Happiness is the most common reason owners will see their dogs tail swish, but it becomes deeply conditioned behaviour as they grow up – making it a useful way for owners to understand their basic needs. A friendly tail wag will appear very loose with no tension at all. Depending on where your dog normally carries their tail, it will be in a natural position for them and whoosh freely.

Labrador Retrievers and Spaniels are two great breeds to look at as an example of the classic, happy dog tail wag. When they wag their tails, it’s not only restricted to their tail movement but their whole spines seem to move with them and create this very friendly full-body wiggle.

Every bit of dog body language needs to be taken in context and a tail wag isn’t always a happy greeting. If you approach a dog and they’re super wiggly and excited partnered with approaching you, it’s usually safe to assume they’re excited to see you. If they seem a little stiff or their posture is lowered, they might be a bit anxious when greeting you so take things slow until they gain their confidence.

Just like humans, dogs experience dreams as they sleep. If your pup is wagging their tail in their sleep, it’s a sign they’ve entered REM sleep – one of the deep levels of their slumber. During this deep sleep, dogs can seem to experience lots of different emotions and perform motor functions like tail wagging, leg twitches or even barking and whining.

Both puppies and older dogs tend to do this more just because they have deeper sleep cycles. Sleep is essential to a puppy’s growth cycle, whereas senior dogs need more rest to regain their energy, so it’s natural that they have deep levels of sleep. 

Even if your pooch is whining in their sleep, don’t worry too much. The VCA Animal Hospital reports that dreams are rarely nightmares for our four legged friends so, it’s best to let them have uninterrupted sleep.  The motions are not necessarily linked to the emotions you may perceive them to be. Just because your pooch is whining in their sleep doesn’t mean they're distressed, just like a tail wag might not mean they’re having a particularly good dream. It’s only an indication that they are in fact dreaming and it’s nothing to worry about. 

If you notice your dog’s tail wagging very quickly in sharp motions, more like a shiver, they could just be cold, especially if they’re a short, coated breed. Placing a blanket over them will provide an extra level of warmth they need, which should help them settle better.

If a dog is doing a nice loose tail wag along with a bark, chances are they are very excited to see you. Sometimes our pets can’t possibly contain their excitement and just being happy to see you isn’t enough. They have to shout about it to let you know that they’re beyond just happy. Barking, just like tail wagging is a form of communication and in the context of a happy tail wag, it can be used as a greeting.

If you were to approach an unfamiliar dog that is barking and wagging its tail, it doesn’t always mean they’re excited to see you. If their tail is tucked between their legs and wagging in small, slower movements, this is a worried tail wag and the bark could be telling you that they’re not sure about approaching.

A dog with a stiff, upright tail wagging partnered with a bark can be them trying to create space and tell you to stay back when they’re quite sure about you. If they’re approaching you slowly or even lunging, they’re really asking you to move back so a tail wag is all about the context it is given in.

Not all dogs wag their tails and there can be lots of different reasons for that. Some breeds are more likely to than others. For example, breeds like the English Bulldog, French Bulldog and Pug have all been bred with little to no tail or a short corkscrew-like tail. It makes it harder for these breeds to communicate through their tail, but you might notice a bum wiggle at most from them rather than a tail wagging.

Other dogs may have suffered injuries such as limber tail that can affect lots of different dogs and cause their tail to become limp, making wagging difficult. Even suffering from arthritis may make them less likely to wag their tail, as their joints become stiff and they’re less likely to wiggle like they used to.

If you’ve rescued a dog and they don’t seem to wag their tail, it could just be a matter of time until they find their confidence after they’ve settled. When some puppies are removed from their mother too early and then not socialised properly, the behaviour is never reinforced, so they’re less likely to use it as they grow older.

Every dog is an individual and reading their body language always means taking everything into context and not just one small clue. To keep your pooch happy and their tail wagging, stock up on everything you need from our dog range in-store and online.