Why Do Alligators Sit With Their Mouth Open? (5 Reasons)

Why Do Alligators Sit With Their Mouth Open

Alligators are fascinating creatures, reminding us of a past that predates us all. So, it’s unsurprising to find so many scientists and researchers trying to understand why alligators behave the way they do, whether we’re talking about their infamous death roll, or alligators sitting with their mouths open.

So, what are some of the reasons that alligators sit with their mouth open?

Alligators bask under the sun with their mouth open to breathe, and to avoid overhearing. Gators are ectothermic, but because they can’t sweat, prolonged mouth gaping helps them release the heat they absorb. Gaping also helps them appear intimidating and to lure prey like flies. Crocodiles also get their teeth cleaned by birds and fish.

If you want to learn more about mouth gaping in alligators and crocodiles, whether they do it when they’re asleep or underwater, then keep on reading!

Why Do Alligators Sit With Their Mouth Open?

Alligators and crocodiles are often seen sitting with their mouth open, also known as mouth gaping, which might seem like a relatively innocent thing to do, but this behavior is actually quite complex and it’s not always easy to draw clear conclusions as to why several species of crocodilians choose to do it.

So, let’s look at the most common reasons behind mouth gaping in alligators!

Reason 1: To Breathe

The most simple explanation as to why alligators sit with their mouth open is to breathe. Alligators, like most crocodilians, have a palatal valve at the back of their throats that they can close and open depending on their environment.

For instance when an alligator is submerged, even if they have their mouth open they keep the valve closed so no water can come through. When the alligator is on land and basking they will keep their mouths open and that’s where they will mostly breathe through.

In some cases, breathing through the mouth can facilitate breathing, especially when the levels of humidity are high and it’s possible that alligators that might be suffering from respiratory illness will also rely more on mouth breathing.

Reason 2: To Regulate Their Body Temperature

Most crocodilians, which includes alligators, will keep their mouth open when basking. That’s because alligators are ectothermic, meaning that the regulation of their body temperature depends on external sources, that’s the sun and the warm rocky surface they sit on.

Because alligators can’t regulate their own body temperature they will often bask under direct or indirect sunlight, which causes their temperature to rise, however, alligators can’t sweat so they have no way of releasing the heat they absorb, so that’s when mouth gaping comes into play.

Just like dogs in a way, alligators will sit with their mouths open and pant for prolonged periods of time primarily to keep themselves cool. Of course, if the heat becomes too much they will avoid the sun completely by moving to a shady area, or they will enter the cool waters or dig barrows to cool themselves off.

Reason 3: To Intimidate

While alligators will most likely sit with their mouth open to regulate their body temperature it’s also possible that there’s a social function behind this behavior.

Mouth gaping isn’t considered an aggressive behavior, but it could help the alligator appear larger and more intimidating. Aside from being an agonistic behavior toward other non-crocodilians, it can also be a display of dominance toward other alligators.

Reason 4: To Lure In Prey

Another possible explanation could be snacking. I mean all an alligator has to do is stay still with their mouth open and wait for flies to enter their mouth. It’s also possible that alligators will use this technique to lure other small unsuspecting critters, though the chances of that happening are minimal.

Reason 5: Dental Hygiene

The American alligator has another reason to sit with their mouth open, but this time underwater, and that’s to get their teeth cleaned. Instead of eating the small fish while they’re submerged, they will let small cleaner fish pick at their teeth!

Why Do Crocodiles Sit With Their Mouth Open?

Just like alligators, crocodiles will also sit with their mouth open when basking, and they do it for the same reasons, to breathe, to regulate their body temperature as well as to appear intimidating, and in some situations even to lure in prey like flies and fish. Crocodiles have another similar reason to sit with their mouth open, and that’s for dental hygiene.

While that might sound very strange, Crocodiles that live in the range of a very specific bird called the Egyptian plover or crocodile bird, will leave their mouth open to get their teeth cleaned by these small birds. The Egyptian plover will remove bits of food that are stuck between the crocodile’s teeth, thus getting a meal for itself while the crocodile gets their teeth cleaned, keeping it free from infections.

Aside from hygiene the Egyptian plover also serves as an alarm, if this bird gets startled and flies away, it will alert the crocodile of a potential threat.

Like alligators, crocodiles will also sit underwater with their mouth open and while they might do it to lure in prey, mouth gaping underwater will also get their teeth cleaned by small cleaner fish.

Can Alligators Sleep With Their Mouth Open?

While we can’t be certain if an alligator is asleep while they bask under the sun with their mouth open it’s definitely not uncommon.

Since alligators are diurnal they are mostly active at dusk, but in some cases, alligators can be more active during the night and sleep during the day. This means that an alligator that’s enjoying the warm sun is most likely sleeping and since they need to make sure they don’t overheat they will leave their mouth open.

Can Alligators Keep Their Mouth Open Underwater?

Yes, alligators and other crocodilians like the crocodile for example can keep their mouth open underwater all thanks to their unique anatomy.

Just like in humans, “their nasal cavity and mouth are separate, with an opening at the back of the throat instead,” says Dr. Stephan Spiekman “However, crocodiles have the gular valve behind the mouth which can separate it from the nose, allowing them to breathe even if their mouth is underwater.”

Similarly, alligators also have this palatal valve at the back of their throats which they can use to stop water from going down their throat. This way they can hunt underwater, or stay submerged and sit with their mouths open for up to 2 hours.

You can see in this video the alligator swimming with his open mouth fully submerged!

Can You Stop An Alligator Or A Crocodile From Opening Their Mouth?

Alligators have one of the strongest bite forces in the animal kingdom, and crocodiles can close their jaws with even more force, with a bite force of 3,700 pounds per square inch.

Once the alligator or crocodile bites into their prey their jaws lock and it’s almost impossible to open their mouths, however keeping their mouths shut doesn’t take much effort, that’s because the muscles that open the jaws are weak.

So, this is why, according to Auckland Zoo, humans could restrain an alligator’s and crocodile’s jaw by holding the jaws shut with just their hands. But even if you can I would recommend that you stay away from these giant reptiles no matter what!

Closing Thoughts

Alligators seem to be the chillest animal, after all, they spend most of their day sleeping, floating in the cool waters of slow-moving rivers, lakes, swamps, and marshes. But even when they’re on land they seem to bask under the sun or shade.

What’s even stranger is that they tend to sit with their mouths open. Of course, there’s an explanation for almost everything and this includes the mouth-gaping behavior of alligators and other crocodilians. From something as simple as breathing and regulating their body temperature, mouth gaping is also an intimidation and luring technique as well as a way to keep their teeth sparkly clean with the help of birds and fish!

Hopefully, our answers satisfied your curiosity and now you can impress your friends with your newly acquired alligator knowledge!