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7 Shocking Reasons Why Crested Gecko Opening Mouth Wide

7 Shocking Reasons Why Crested Gecko Opening Mouth Wide

The crested geckos are known for having some peculiar sleeping routines. They are susceptible to rest in a vertical, upright position, and others have been sleeping in water basins! If you notice an unusual pattern in your Crestie resting on its back with the mouth closed, you could be wondering if it’s the regular sleeping pattern of an extended gecko. Let’s learn: Why Crested Gecko Opening Mouth Wide

Why Crested Gecko Opening Mouth Wide?

In the following article, we’ll look at why the crested geckos tend to rest with their mouths shut and their mouths open in various ways, from relaxation to respiratory diseases. We’ll also discuss Why Crested Gecko Opening Mouth Wide at any moment of the day.

Why Crested Gecko Opening Mouth Wide
Why Crested Gecko Opening Mouth Wide

The crested gecko may be asleep in a closed mouth as its jaw relaxes while it sleeps or is controlling its thermoregulatory. Open mouth could be a sign of respiratory illnesses.

Reason #1: Temperature Regulation

Many reptiles have unique traits that use your mouths to regulate body temperature. However, they do not all possess this ability. The crested geckos belong to the snakes that have this ability. They are exceptionally intelligent reptiles with unusual behavior that could help them deal with various situations.

One of these is the regulation of body temperature they display, referred to as gaping. This occurs when they use their mouths to speak for a prolonged duration. It is not uncommon to observe giant reptiles such as crocodiles making this noise along the edges of rivers and lakes.

This helps them manage their body temperature and prevents them from becoming hotter than their optimal temperature. If your geckoes are doing this as they’re basking in their area of basking or under their bulb, there is nothing to worry about.

This is typical for Cresties. The Cresties cannot sweat, as that’s how mammals regulate their body temperature. Reptiles have their way of handling their temperature, allowing them to control their body temperature, and that’s how they manage it.

Reason #2: Temperature inside the tank.

Although it’s normal for crested geckos at their basking areas with a gap, It is essential to make sure that you supply your crested gecko appropriate temperature for your tank. If the tank is not at the recommended temperature, it will be more difficult for your Crestie to regulate their temperature, and they’ll have a longer time looking around.

Also, make sure that your tank is fitted with a cooling area that allows the geckos to cool down when they reach their ideal temperature. Be aware that the crested tank has to include three temperatures.

The basking zone must be between 95 to 100 degrees F. The cool part of the tank of your crested gecko must have a temperature of between 80 and 75 temperatures F. The tank’s temperature is supposed to be 70 deg to 75 deg during the evening.

Reason #3 Respiratory issues.

The final option is the least likely. It could, however, be the most important option. In most cases, when your Crestie opens its mouth, they’re controlling the body’s temperature.

In other instances, it may be an expression of anger in the event of an incident they don’t like or is triggered by hormones during this time. It is also possible that they are suffering from an infection in your respiratory system.

If a crested lizard develops one of these illnesses, it’s because of the humidity levels inside the tank. They are accustomed to low humidity because that’s what they live in the wild. Therefore, when your tank has a humid environment, it could develop problems for them.

The most efficient method to monitor humidity levels within the tank is to purchase a hydrometer. This will allow you to accurately check the humidity levels in the tank in your Crestie at all times. Humans, for instance, require humidity levels between 30 and 50% to remain healthy, which is what’s ideal for humans.

The crested geckos need levels between 20% to 40 percent. If you can control the humidity in your home, you and your crested gecko may be in danger. Hence, it is recommended to try and maintain your home’s humidity at 30 percent. The less humid the environment is, the better for your Crestie.

Be aware that certain items such as an under-ground bark layer and the tank’s decoration could cause an increase in humidity since they may hold water. If you’re having trouble keeping the humidity at a minimum, you have to be aware of these factors. Smaller water containers can be beneficial, as well as keeping them from hot sources can help in this process.

The objective is to maintain the level lower. This isn’t difficult; however, it’s contingent on the area of your residence and the place where you live. If the issue becomes more serious, it is possible to consider using dehumidifiers to get rid of the problem. If you suspect that your Crestie has an infection in your respiratory tract, it’s ideal for taking them to the veterinarian to have their condition checked.

Reason #4: Temperature Gradient

The crested geckos don’t just require space to bathe, but they also need space to cool down. Having the space for basking and cooling space can help regulate their temperature. Be sure to have a cool room.

If you do not, if the temperature isn’t right, your Crestie could begin to appear happy in a significant amount since it doesn’t have the option of removing the basking zone for an area that is more comfortable in the event of having to move. Ensure your tank is within the correct temperature range for the cooling and basking areas.

It’s also essential to ensure that your tank is kept at the proper temperature at night to ensure that your gecko is not too hot or cold the next day. The tank’s temperature needs to be accurate to ensure that they’re healthy and happy.

Reasons #5: Aggression

Geckos with crested crests are peaceful reptiles. But they can also be aggressive. If they do, it’s normal to see them utter an oath in a frightening display. This isn’t the only way that they show aggression. If they’re acting out aggressively, you should search for other warning signs.

They are usually characterized by a fast head bobbing, large beards, and an oversized or tall posture. Your Crestie is not likely to display any of these characteristics. Still, when their mouths are open in a threatening manner, you’re likely that they will say at minimum one of these savage behaviors.

Offering a Crestie a home with many places to hide will help to reduce the aggression they exhibit. Typically, the charge is only displayed when they feel threatened, if they have a safe place to be safe and secure, and do not have to show aggression.

Interesting Further Reading

Reason #6: Small objects or toys

Although it may appear odd initially, the gecko you have spotted might open their mouth in response to toys for children or other objects, such as socks or similar items. Your gecko could be aggressive toward these items that aren’t animated.

This is an odd concept since we are aware the inanimate objects are… it doesn’t animated. But, they aren’t aware of this and could be able to misinterpret toys for predators or comCrestieition.This can cause them to behave aggressively and open their mouths.

They could also have the ability to grow their beards and even shout at objects that aren’t animated. As with toys and other inanimate objects, for instance, if you have recently been to the local china shop or an auction and bought your loved one a new jewelry item.

It’s a great idea; however, your Crestie could also find it alarming. It is crucial to be aware of how Cresties aren’t fans of changes. They do not like the idea of the seasons, which could create stress and anxiety; even if you’re an admirer of the design, they may be skeptical about it. They might even attempt to make it appear not very comforting initially.

The fact that clothes and toys are typically moved around quickly implies that they won’t create any problems over more extended periods. But, ornaments, decor, and other items for stationery are generally placed in one location and will likely remain in that place.

If you suspect that an item you have been using for a while might be causing problems for your crested gecko, it’s essential to move it to stop your Crestie from becoming stressed over it.

Reason #7: Fight between Cresties

In light of the previous problem, If you have multiple crested geckos within the same habitat, there could be issues because they’re not a very social species and prefer living in solitude. If a crested animal needs to share space with a gecko, it could lead to an argument for control and dominance.

The one Crestie tends to be the dominant one and grow their influence on the other. This is why we can see their mouths and animals being slashed open. This is similar to an act to show the strength, size, and power they possess.

If you have two crested geckos in which both are in an area together, it is best to separate them before things turn nasty. The one that loses its power could be harmed, which can cause injuries and loss of the ApCrestieite.

Then, in the long run, the Cresties may not be able to experience the pleasures of the dominant Crestie, which could result in health issues. There is a way to divide your Cresties into separate rooms when they remain as one. The battle to be the best could bring anxiety to both the Cresties and you.

If you’re in the last option, if you don’t have enough room to store each of your Cresties in separate tanks in your home or it’s not possible due to a different reason, you may have one or both of your Cresties for someone else because they won’t be in the position to live together.

It can be rough and uncomfortable at first. However, keeping two Cresties close in case one is dominant may be harmful to the well-being, and it’s better to give one away to a new place of residence rather than allow one to be afflicted by health issues due to that dominant Crestie.


We’ve covered every reason that a crested gecko might remain mouth-open. It is most likely due to the body’s temperature, and it could also be due to hormones, stress, and respiratory illness. In the end, you should remain aware of humidity and temperature levels within the tank.

If you spot unusual behavior, identify what is troubling your Crestie and then take care of it. As long as you’re doing these actions, everything is perfect. When your dog’s mouth appears open, they’re likely to be taking care of their temperature. If you’re concerned, you should consult your vet for an opinion from a doctor.