The Very Cool Reason Your Beardie is Basking With Their Mouth Open

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bearded dragon basking with mouth open featured image

Bearded dragons are extremely cool creatures. If you choose to adopt one of these animals, be prepared for some interesting behaviors. One of those behaviors is basking with their mouth open. As they sit there with their jaw hanging open, you may wonder what they are doing and why!

Bearded dragons sit with their mouths open to regulate their body temperature. Scientists call this action “gaping.” Bearded dragons often gape while basking in the heated area of their tank. If a bearded dragon is gaping in the cooler area of its tank, this could mean the tank is too hot.

If your bearded dragon starts gaping, there’s little need to worry. However, there are some rare situations where you may need to take them to a vet. To learn more about why your beardie doesn’t want to shut its mouth, continue reading!

Why Do Bearded Dragons Leave Their Mouth Open?

Bearded dragons leave their mouths open as it’s their only way of regulating their body temperature. Beardies require external heat for digestion and other important bodily functions. They “thermoregulate” this temperature by opening their mouth to cool down or closing it to keep heat inside.

If you’re new to the world of caring for bearded dragons, certain actions, such as gaping, may surprise you. However, once you know the reasoning behind this behavior, you can relax knowing that your beloved pet is happy and healthy.

What Is Gaping In Bearded Dragons?

Gaping refers to when a bearded dragon leaves their mouth open for an extended period of time. In most cases, the bearded dragon will do this when sitting under the heat lamp, also known as basking.

Beardies bask in direct heat to raise their internal body temperature. When they’ve reached the optimal temperature, they need to maintain that amount of heat. To do so, they open their mouths. Bearded dragons don’t have sweat glands. For this reason, the only way to let their excess body heat escape is through their mouth.

As the heat dissipates through their mouth, they continue to sit in the heat, enjoying the perfect internal temperature. In other words, there is very little need to worry when you see your bearded dragon sitting with its mouth open. However, if your bearded dragon sits with its mouth open outside the warmer side of its tank, you may need to make some adjustments or take them to the vet.

As we already know, beardies open their mouths to help regulate their body temperature by expelling excess heat. If you see your bearded dragon gaping on the cooler side of the tank, it could mean that the entire tank is too warm.

The North Carolina State Veterinary Hospital suggests keeping the cooler side of your bearded dragon tank between 75 and 85 ℉ during the day and between 70 and 75 ℉ at night. Meanwhile, the basking side of the tank should remain between 88 and 100 ℉.

Remember, if you need to raise the nighttime temps, don’t do it with a light. Instead, use a ceramic heat emitter (you can see the one we use here on Amazon). We do NOT recommend using an under-tank heat mat to warm the bearded dragons from the ground up. These can cause burns and other problems.

Beardie with its mouth open

You may need to keep the tank warmer if you have baby bearded dragons. For baby beardies, keep the cooler side of the tank between 80 and 90 ℉.

Keep a close eye on the temperature of your bearded dragon tank as well as how the dragons react to the heat. If they spend all day with their mouth open and hiding in the shade, lower the temperature by a degree or two. Watch for changes in behavior before adjusting the temperature further.

Another sign that the temperature in your tank is too warm is if your bearded dragon spends a lot of time in its water bowl. While it is normal for a bearded dragon to soak once a week or so, anything more frequent may be an attempt to lower their body temperature.

Other Reasons a Beardie Leaves its Mouth Open

If heat isn’t the cause of your bearded dragon leaving its mouth open, it could be several other non-threatening reasons.

First things first, consider the last time your beardie shed. Young bearded dragons shed their skin more frequently than adults. To help loosen up the old layer of skin, your bearded dragon may open its mouth wide and puff up its beard regularly. This isn’t harmful to them. Check out our full guide on shedding and what to do about it here!

If it’s been a few weeks since your bearded dragon shed its skin, don’t be alarmed by them leaving their mouth open on occasion. However, if the behavior continues after they shed their skin, there may be something else going on. For example, some bearded dragons leave their mouth open if they feel threatened or sick.

Bearded Dragon Respiratory Infection

While most scenarios where a bearded dragon leaves its mouth open aren’t life-threatening, it could also be a sign of a respiratory infection. If your bearded dragon has a respiratory infection, it’ll likely experience other symptoms too. These may include mucus buildup, coughing, and raspy breathing.

Your beardie may develop a respiratory infection due to increased humidity levels. In addition to thermometers, you could use a humidity gauge to keep an eye on rising humidity. The North Carolina State Veterinary Hospital recommends maintaining a humidity level between 20 and 40 percent. For specifics on how to measure, achieve, and maintain proper humidity, check out our detailed article here!

Bearded dragon on shoulder with mouth open

If your bearded dragon shows signs of a respiratory infection, take them to a vet as soon as possible. While you could attempt to let the infection clear up on its own, it is a much safer option to get your beardie the help they need.

You can prevent your bearded dragon from developing a respiratory infection by only using non-absorbent tank materials. While moss might look cool in the tank, bearded dragons don’t live in environments wet enough to support it. Only use substrate similar to what a bearded dragon would live in naturally. To see the ONLY substrate we use and recommend, see our substrate handbook here.

Additionally, consider using a smaller water bowl. Bearded dragons should be bathed a few times per week. This should be done in a separate bathing tub (for full beardie bathtime instructions with pictures, see our guide here!).

What To Do If Your Beardie is Gaping

Well, nothing! If they are doing it under their basking lamp, it’s just another one of those quirky beardie behaviors all beardie owners come to love. We like watching Bacardi gape as it’s a great photo op, and we like looking at her little dinosaur teeth!

Bacardi the bearded dragon with her mouth open and gaping
Our little Bacardi basking with her mouth open.

Sources and Further Reading

Thermoregulation and aggregation in neonatal bearded dragons (Pogona vitticeps)

The Effect of Thermal Quality on the Thermoregulatory Behavior of the Bearded Dragon Pogona vitticeps: Influences of Methodological …

Hot and covered: how dragons face the heat and thermoregulate

Level and precision of behavioural thermoregulation in the bearded dragon, Pogona vitticeps: effects of hypoxia and environmental thermal quality

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Tim Steward is a life long pet owner who is currently raising a beautiful little beardie named Bacardi along with two Australian cattle dogs named Anny & Beans. Bacardi is one in a long line of bearded dragons that Tim has rescued, rehabilitated, and rehomed. Through Beardie Bungalow, Tim has helped thousands of beardie parents give the best possible life to their pets.

18 thoughts on “The Very Cool Reason Your Beardie is Basking With Their Mouth Open”

    • Always make sure your basking temps are correct, we have a full article on that. But your beardie isn’t going to sit there if it really is too hot. That’s why you need to make sure they have a cool side of their enclosure too (kept at 75* F).

    • Well, now you know! We can relate. Vet visits are expensive and we’ve gone to more than a few that we didn’t really have to. But we prefer to err on the side of caution, so it is what it is!

  1. We always thought our bearded dragon was smiling at us when they did this. We just assumed they were really happy in their basking spot! This was a super interesting article to read, thank you!

    • Ha! I never thought about that, but you are right! They really do look like they are grinning. I’ll bet they are happy in their basking spot too, though.

    • Just make sure the temps are in the right range as measured with a temp gun. This behavior is normal and tells you the basking spot is probably warm enough. If it’s too hot, they won’t sit there, even with their mouth open.

    • I would check your temps in this case. The cool side of your tank should not be hot enough to make them thermoregulate. Odds are your temps are too high. Make sure you have a basking spot set at the right temps and then make sure you also have a cool side that is 75-80 degrees F.

  2. I noticed my bearded dragon was missing some teeth when they were doing this. Should I take them to a vet? I have no idea how they could have lost teeth!

    • This is normal! Beardies can and do lose and regrow their teeth. If you look close you can see the new ones ready to come in when the old ones fall out. If you think they’ve sustained an injury of some type, though, for sure take them to the vet.

  3. We always try to stick a green bean in our bearded dragons mouth when they are doing this. They sit there like they’re smoking a cigar and it’s hysterical!


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