is mouth gaping in snakes normal?
Questions About Snakes

Why Do Snakes Yawn?

As a snake owner, you will have noticed that your snake yawns occasionally. But unlike in humans, it’s not because they’re feeling a bit tired. There are many reasons for yawning in snakes, and none of them are to do with how much sleep your snake got last night.

What does it mean when a snake opens its mouth? There are three reasons for mouth gaping in snakes. 1/ Snakes yawn because they have to realign their jaw after a large meal. 2/ Snakes are picking up chemical cues from their environment. 3/ It could be a sign of disease in snakes.

By identifying some of the most obvious clues, you can figure out why your snake is yawning. You can then determine whether it’s something worth investigating further.

Do Snakes Yawn When They’re Tired?

A study in the journal Physiology & Behavior sought to prove that humans yawn due to temperature. A big inward breath cools the body by cooling down the blood that visits the lungs.

The scientists took a look at when people yawn to try and prove their idea and found that yawns were far more contagious during the summer rather than winter. Whether they were entirely correct isn’t certain because, like all ideas in science, it’s still possible that it could be disproved.

And if this is true, it would mean that snakes wouldn’t yawn because they’re tired. In truth, we don’t yawn because we’re tired—the scientific evidence seems to suggest we yawn because we’re too warm, or because our breathing has slowed down. And because snakes are cold-blooded whereas we’re warm-blooded, it’s unlikely that they would yawn for the same reasons that we do.

Whatever the case, snake owners don’t report any link between snakes being tired and yawning.

So Why Do Snakes Open Their Mouth Randomly?

What does it mean when a snake opens its mouth if it’s not to do with tiredness?

It can be one of three things:

  1. It can be due to eating and the unique mechanism behind their jaw. They have to yawn to be able to use it properly because unlike us, they don’t eat in tiny portions.
  2. Sometimes snakes yawn because they’re picking up on chemicals in the air. They usually use their tongue to do this, but sometimes it just doesn’t provide enough information, and they yawn to pick things up instead.
  3. Your snake could be yawning because it’s ill. The reason why we humans yawn might be to do with not getting enough oxygen, and as it turns out, snakes might do the same.

Do Snakes Yawn Before Eating?

Yes, they most definitely do. It’s all down to the kind of prey they eat, and how they eat it. Snakes don’t have incisors and molars like humans. Of course, most have fangs.

What you might not know is that snakes can stretch their jaw incredibly wide, so that they can eat all of their food at once. And this isn’t done by dislocating their jaw, as you might have heard.

Snakes don’t have a chin that connects to their upper jaw and skull. All they have are stretchy ligaments that hold their lower mandible in place. This means that they have to stretch their ligaments to be able to swallow prey that can be even bigger than their head.

To us, though, that looks like yawning. So if you notice your snake yawning before they eat, it’s nothing to do with them feeling sleepy before their supper. It’s to do with them preparing their jaw to eat their prey in one go.

do snakes yawn before eating?

They can also yawn after a heavy meal. This is because they’re realigning their lower jaw after they opened it so wide. It could also be because they swallowed a lot of air after their meal, and they’re breathing out, not in. To put it simpler, it could be because they’re burping after they’ve eaten.

And in case you didn’t know, this instance of yawning isn’t a problem. It’s all a part of natural snake behavior that you can find either in captivity, or in the wild, and it’s nothing to worry about.

Snake Keeps Opening and Closing Mouth

The frequency and timing of your snake yawning are what can give you a clue.

If you notice that your snake only yawns before and after food, then there isn’t a problem. They’re aligning or re-aligning their lower jaw after they had to stretch it out to eat a large prey item. That’s a part of their behavior in the wild, no matter what species you keep as a pet.

However, if you notice that your snake keeps opening and closing mouth regardless of what they’ve been doing, this could be a sign of sickness. Let’s take a look at what might be wrong.

Is Snake Yawning a Sign of Disease?

It definitely can be. Yawning is a symptom of some illnesses, although not all.

The most obvious connection is between yawning and respiratory disease. Respiratory issues in snakes, like those in any other animal, cause the animal to have trouble breathing. They, therefore, need to expend extra effort to breathe in, to keep functioning normally.

Snakes normally breathe through their nose, and if they’re having difficulty keeping their airways open, they won’t be getting anywhere near enough air this way. That’s when they start yawning.

If the problem is pneumonia, you’ll notice them yawning consistently. Other symptoms include anorexia, gurgling noises, bubbles around their mouth and nasal discharge (snot/mucus). They may start rubbing their nose against the walls of their enclosure, which can help clear their airway.

Respiratory infections can come about because of a variety of causes. Most are related to incorrect care, in that either the temperature is too low, or the humidity is too high.

These things can help the infection to flourish. But the underlying cause may also be related to heavy infestations by mites or other parasites, or even malnutrition.

Inclusion Body Disease

Inclusion Body Disease is a relatively new infection that affects snakes and is always deadly. It’s vital that you spot it, at least to prevent your snake ever passing it on.

IBD usually affects Boids (boa constrictors and other related snakes) but can affect other species too. It’s an infection that spreads from snake to snake, similar to human infections like flu.

Unfortunately, people aren’t sure how it spreads from snake to snake. It seems to be through direct contact, but it may also be passed on during birth or spread by mites.

IBD has many symptoms, although some may occur while others don’t. The most common are corkscrewing of the head and neck, where the snake curls itself up like a corkscrew and stargazing where the snake gets stuck staring upwards at an unnatural angle.

Why do snakes open their mouth randomly?

Stargazing may also co-occur with mouth gaping, where the mouth is held open for extended periods of time, which is the same as snakes do when they can’t breathe properly.

So, look out for the following signs of IBD:

  • Stargazing
  • Corkscrewing
  • Moving in a disoriented fashion
  • Regurgitating or not eating

Then the problem may be inclusion body disease. There is no known cure for IBD, and it has been killing pet snakes for decades now with no way of stopping it in sight.

Other Reasons for Snake Yawning

Like we said from the start, snake yawning also seems to be linked to chemical communication.

Chemical communication is where an animal picks up cues from its environment about mates, threats, prey and so on using the chemicals they can find in the air, or that another animal left behind. An example that even we humans use is hormones and pheromones.

Even though we can communicate through speech and other means, we still give off pheromones just like other animals, although we’re not that great at detecting them.

Snakes have a fantastic sense of smell. They have a specialized organ in the area of their nose dedicated just to detecting these chemicals, called the vomeronasal organ (or Jacobson’s organ).

This organ is similar to the sense of smell but specifically finds the chemicals that prey and other predators give off. This helps snakes either find something to eat or avoid being eaten themselves.

We have a vomeronasal organ too. It’s located in the nose, but unfortunately, scientists can’t tell if it does anything. It’s also present in other mammals like dogs, and you can see them using it when they sniff around searching for scents. They do something called the ‘Flehmen response,’ where they move their lips back and expose their gums while sniffing.

A paper in the journal Heliyon examined the issue, specifically related to the topic of yawning. The team of scientists discussed how rattlesnakes seem to ‘yawn’ more often when they’re exposed to certain chemicals in the air.

So, presumably, yawning could be helping them pick up these smells from the environment.

How to Help a Snake that Won’t Stop Yawning

So, is mouth gaping in snakes normal? By now, you should know that the answer depends on what’s wrong. And it’s crucial that you figure out what’s wrong, just in case there’s something that your snake needs help with.

Diagnose your snake with the following checklist:

  • Does your snake only yawn when they’re offered food, or after they’ve eaten? If so, this is nothing to worry about.
  • Does your snake yawn when you introduce them to something new, either in their enclosure, or when you’re handling them? If so, this is a sign that they’re using their vomeronasal organ to investigate their surroundings.
  • Does your snake yawn and display other symptoms? If so, this might be a sign of disease.

If your snake only yawns in specific scenarios, then leave them be, because they’re fine. If your snake also displays other symptoms, either those associated with RI (respiratory infection) or IBD (inclusion body disease), then take them to the vet for a formal diagnosis. If your snake has RI, then your vet will be able to prescribe them something to help beat the infection.

Unfortunately, if they have IBD, then there’s nothing that anybody can do to help. You should make sure that your snake doesn’t come into contact with any other snakes you keep (if you have any), and that you wash your hands whenever you handle them.