Why Is My Dog Wagging Its Tail Whilst Asleep?

Photo by Rae Allen on Flickr

Imagine you’ve had a long day, you return home tired, turn the doorknob and suddenly there is a four-legged creature running excitedly towards you.

He’s big and strong and so glad to see you, you see his fluffy tail wagging, he jumps on you giving you a furry hug.

Beautiful scene, yes?

That four-legged creature is your dear dog (you can insert your dog’s name at this point).

It makes you remember the words of Kinky Friedman: “Money can buy you a fine dog, but only love can make him wag his tail”. 

Tail wagging, oftentimes we’ve seen this as a sign of happiness, excitement and just an awful glad dog.

Well, studies have shown that that isn’t always the case.

An instance of this would be a sleeping dog wagging its tail, does this sound familiar? What does this mean?

We’ll see.

Why do dogs wag their tails while they sleep?

To answer this, we need to clear up this question: do dogs dream?

What do you think?

You could ask your dog if it dreams, well, we sure won’t get an answer from your dog or any other dog.

And it’s pretty obvious why.

Unlike humans who speak, our dogs communicate by barking or body language.

Dogs, like humans, have a deep sleep stage called rapid eye movement(REM).

At this stage, it’s deep asleep and this is when dreaming occurs, you would notice the eyeballs moving behind the eyelids, scientists say this is when dreaming occurs. 

Remember the day you went out, had a swell time and returned home beaming with happiness, can you recall sleeping well that night? 

You might have even smiled in your sleep.

Well, the same thing happens to your dog.

It might have had a fun-filled play day, received treats and just enjoyed chasing birds in the park.

When it finally rests these activities can give rise to dream-like actions such as tail wagging, paw twitching, whimpering and sometimes barking.

Sleep behaviours vary, and most times tail wagging is done unconsciously while your cute companion sleeps.

So, what does it mean when your dog is awake and wags its tail?

When dogs aren’t asleep how do dogs use their tail to communicate?

Facial expressions are the easiest ways humans convey their emotions, so a smile may not always show happiness, it could show embarrassment, true?

Each expression has a different meaning, we hope the recipient translates it properly to understand what we are trying to communicate.

The same thing for dogs. Tail swinging can be interpreted based on: tail motion and placement. We could interpret it to mean:

  • Anger or aggression: Generally, a vertical stiff tail is a dog’s way of communicating aggression.
  • Anxiety or fright: If your dog holds its tail in a lower position and in between its legs even if it’s wagging then it could be frightened. Watch out for other signs it gives with its body language.
  • Guilt or submission: Dogs look adorable when expressing guilt. So, if your dog is slowly wagging its tail, and looking at you, it probably feels guilty for munching on your favourite pair of shoes. Try to reassure him, it’s fine, even if he has done something naughty.
  • Curiosity and focus: If your dog’s tail is more strengthened and erect, he likely is focused on something. His attention and inquisition level are pretty high. 
  • Emotional hints: Studies have shown that if your dog wags a little to the right side, it indicates positive emotions while a wag to the left shows negative feelings.

It is important to note, however, that tails aren’t only communication tools, they are also used for: 

  • Stability and balance: You can get a clearer picture of this when you watch your dog in slow motion as he turns at high speed.
  • Swimming purposes: When your dog swims its tail acts as a steering wheel. Amazing!

So you’ve had a great day with your dog and it’s time to rest; do your sleep habits differ?

How different are your sleep patterns?

How does dog sleep differ from human sleep?

Daily, humans require about 7 to 9 hours of sleep.

Depending on their age, size, personality, breed, feeding habits and level of activity, sleeping habits vary among dogs.

Generally, dogs sleep a lot more than humans, most adult dogs sleep about 8 to 13.5 hours.

Dogs nap for about 3 hours during the day and sleep most of the time at night.

Young puppies like human infants sleep for about 18 to 20 hours a day to support their brain and body development.

16 weeks old puppies sleep an average of 11.2 hours daily or even up to 14 hours.

Dogs sleep for 45 minutes at a time, and have only two sleep cycles during this time, unlike humans that have longer sleep cycles lasting for about 70 to 120 minutes each time. 

Dogs raised in quiet environments tend to sleep more, while those raised in more active, bustling environments sleep less.

The good thing is, dogs can adjust their sleep habits to their environment, so they are awake and alert when they need to be and sleep at other times.

When dogs are asleep, probably deeply asleep, it is important not to wake them, this could startle them and result in unintentional bites.

Kids are often the victims of this, it’s important to train kids to always “let the sleeping dog lie” whenever dogs are asleep.

Dogs can be grouchy too when their sleep is interrupted.

What other behaviours can we see in sleeping dogs? And what do they mean?

Apart from wagging their tails, your dog could whimper, twitch or even bark while sleeping.

These are normal REM related behaviours.

So you have nothing to worry about.

But watch out, these actions are usually short and unconscious. So if you notice they are longer, stronger and more violent, then your dog might be having a seizure. If he has a health issue it’s best to visit a Veterinary doctor.

Other sleep behaviours could be sleep positions. Dogs have varying sleep positions such as:

  • Belly up: this position indicates your dog is comfortable and very relaxed. It could also signal he is hot and doesn’t need to conserve body heat.
  • Curly ball: a position linked to their ancestors in the wild. They felt vulnerable to wilder animals and so they curl up in a ball to protect their organs and preserve body heat.
  • Under cover: this might just be your dog’s sleep position choice, to sleep under cover or he might just need a company to sleep.
  • Side lay: Most dogs lie on their side to rest and just doze, but they can fall deeply asleep in this position too.

What have you learnt about your dog?

Our furry companions are fascinating creatures. They are the closest to exhibiting human behaviour, even if it’s rudimentary. 

So, do not try to wake your dog when he’s dreaming.

If you have to, don’t startle him.

Do not always interpret his wags for excitement and make sure he gets as much sleep as he needs.

He’ll keep on loving you for loving him first.