Green Iguana Society logo  1999-2001, D. Baze

Most pets communicate with their owners in many different ways. Most people can recognize the obvious ones such as an angry barking dog, a hungry kitten rubbing up against a leg, or a happily chirping bird, but the ways an iguana communicates can be a little bit harder to recognize. Even though iguanas don't bark, growl or make many noticable sounds, they do have many different ways they communicate. Learning how an iguana communicates with people and other creatures, through body language, can be very helpful in forming a happy and tolerable relationship between an iguana and its owner. Throughout this page, there will be several references to various parts of the iguanas anatomy. For explanations about these body parts, please refer to our Anatomy page for more details. There will also be many references about the caution needed to be taken with aggressive iguanas. Please refer to our Breeding Season Issues and Your Health & Safety pages for more information.

The bite is always worse than the bark. To begin, it's important to know that iguanas are very capable of severely injuring people, other pets and even themselves when the body language they use is not recognized. Most iguanas will give you a very clear sign that trouble is ahead. Most experienced iguana owners who have been bitten or injured by an iguana simply weren't paying close attention to the signs. If you learn to see the signs, you and the iguana will be much safer and probably a lot happier.

The dewlap. The first thing you should learn is that iguanas use their dewlap to communicate. There are several things that an iguana can say with their dewlap extended. First of all, an extended dewlap can simply be a greeting of hello. An extended dewlap is often used to say hello to another creature during mating and most generally as a territorial sign. Secondly, it can be a form of protection. A threatened iguana may extend its dewlap to make for a larger presence, which the iguana probably hopes will intimidate a predator into thinking the iguana is much larger than it really is. Thirdly, an extended dewlap can simply be a sign that the iguana is trying to adjust its temperature. An extended dewlap on an iguana basking in the sun is quite normal. It may be catching more sun to warm up or possibly catching a breeze to cool off. Lastly, an extended dewlap combined with other body language can be interpreted differently. So basically, it's important to see the big picture when reading body language.

Head bobbing. This is one of the most noticable forms of body language an iguana uses to communicate. The way an iguana bobs its head can tell a lot about what it's trying to say. Generally, the head bobbing motion is a way iguanas let everyone and everything around them know that they are in charge and in a way, tells them that this is its territory and not theirs. Males usually bob more than females, especially after they have become sexually mature. Many females bob their heads as well, but usually not as often or as distintively as males. A slow, up and down bobbing usually means that it is just letting you know that it knows you are there and it wants you to know that it's there. This slow bobbing is very normal and common for male iguanas and should be expected. A faster motion indicates that it may be agitated and could be a sign of aggression. Another form of head bobbing is a rapid side to side motion, commonly called the shudder bob, that is usually a pretty good sign that it doesn't want to be messed with. If the bobbing motion is very fast, moving side to side and up and down, this is usually a clear sign that the iguana is extremely irritated. With larger iguanas, especially males, it's important to use extreme caution when it displays this kind of head bobbing.

Tongue flicking. An iguana's most important sense is its sense of sight, but somewhere between taste and smell, it has the ability to flick its tongue in order to get more information about something in the area. Anyone who has spent any amount of time with an iguana has seen this behavior and it's a very normal sight. This behavior is much like that of a snake or other reptile that use their tongue for sensory purposes, although it's not as highly developed in iguanas as it is in many other species. They will often flick their tongue at food, new or strange objects (including people and other animals), water, various objects lying around the house (which can be very dangerous), or just because it's trying to learn a little bit more about something in the area.

The tongue flick can also be a good warning sign that it's going to bite as well. It's very common to see an iguana that is exploring a new area of the house or habitat, to have its tongue flicking anything and everything. An iguana's tongue is somewhat tacky and usually if the object it flicks is small enough, it will most generally end up being eaten, even if the iguana doesn't really want to eat it. When your iguana is out exploring, be very careful when you see it in full tongue flicking mode and always make sure you iguana-proof your home to prevent any problems.

Sneezing or snorting. Although sneezing and snorting isn't really a form of body language, it is a very common characteristic of iguanas. Iguanas sneeze or snort to rid their bodies of certain salts. Iguanas do not catch colds from viruses, but they can get respiratory infections from bacteria. Sneezing and snorting isn't usually a sign of respiratory infection. Sneezing and snorting is quite normal, but if the iguana snorts far too often, it may be a sign that its diet needs adjustment.

Tail whipping. This is a very obvious form of body language. Whipping its tail is usually the first weapon an iguana will use to protect itself. It's usually just a painful experience, but preventable none-the-less. They usually have very good aim and the speed of a good tail whip will amaze most people who have never experienced it. You can't stop an iguana from whipping its tail at you, but you can prevent being hit by it. First of all, they will usually show other signs that they are irritated before cracking the whip. Secondly, there may be a twitching or wagging of the tail before it attacks with it. If you see the signs, you should be safe. If not, the damage it can cause is usually not too bad, except for a welt and maybe some hard feelings, although a good aim at the eyes could be very be careful!

Squirming. Another very obvious sign is a squirming iguana. If an iguana is squirming around in your hands, it's a good sign that it isn't happy with being held by you. There are different approaches to dealing with a squirming iguana. One side may say that it is better to let the iguana go and let it decide when it wants to be held, while the other side says that it is better to hold onto the iguana to let it know who's in charge. While you may relieve some stress by letting it go when it wants to, it may be training you to do what it wants. This issue of training is really up to the iguana owner and there really isn't a right way or a wrong way to deal with a squirmer.

Posturing iguanas. One very impressive form of body language is the posturing an iguana does. A posturing iguana is a sight to see and can almost be funny when you see it, although it may not be so funny when the iguana gets its way or causes some damage. There is a good way an iguana postures and a definitely a very bad way.

The good form can usually be seen when it's comfortable and content. A very happy iguana, basking in the sun or being petted will stretch its front legs, standing up tall and raising its head in the air. Many times when an iguana is being petted, it will rise up, close its eyes and many iguana owners will even claim that it cracks a smile.

Now, for the bad form of posturing. It usually involves the iguana turning its side towards you and puffing its body up (making for a larger profile), sometimes combined with a slow, legs-stretched-out type of walk and a wagging tail. This form of posturing is sometimes referred to as "hatchet mode". If the iguana is irritated or intimidated by you (or someone else), it may even combine posturing with a nice, quick tail whip, gaping mouth or even a dangerous bite. This form of posturing should be a clear sign to beware and should be taken very seriously. Here are two examples of "hatchet mode". Notice the way the iguana's bodies are puffed up, dewlap extended and of course, the evil eye they're dishing out...

Digging. Most generally, anyone who has ever had an iguana in an enclosure that was too small has seen their iguana digging. Digging is a normal sign for a female iguana that is preparing a place to lay her eggs. Digging can also be just the action of a curious or mischievious iguana. But, it is usually a sign that it is not happy with its environment. If your iguana is constantly digging around in its habitat, it may be wise to make sure that the habitat provided is set up properly. Chances are, there is a good reason for a constant digging behavior.

Charging. A charging iguana is a dangerous one. Anyone who has ever had an iguana charging at them will tell you that this is a very true statement. The signs are obvious and usually involve a large male iguana charging in attack mode. An adult male iguana is very capable of suddenly charging, and extreme caution should be taken if you suspect that your iguana is in breeding season. Basically, when an iguana charges at someone, it is due to breeding season aggression. If not, it may be a sign that there is something physically wrong with it. If there is no chance that the charging behavior is due to breeding season aggression or other obvious reason, it may be a good time to go to the vet to make sure there isn't a medical condition causing the behavior. There are many ways to deal with a charging iguana on our Your Health & Safety page.

Biting and snipping. Biting is yet another very obvious form of body language. An aggressive iguana can bite just because it feels like it. A hungry iguana may even bite you, thinking you are a tasty treat. A scared or intimidated iguana may bite to defend itself. An iguana that is suddenly approached while it's sitting comfortably in its habitat may snip at an approaching human hand. So, basically, there are many reasons why an iguana may bite. Usually, biting is an iguana's last form of defense. The best possible way to prevent being bit by an iguana is to be cautious. Most of the time, there will be warning signs. These warning signs include much of the body language signs listed here. An iguana that is tongue flicking your arm may even be a warning sign. Many times it may even slowly open its mouth as it begins to bite. Most owners that have been bitten will claim that it was their fault that they were bitten, and not the iguana's, because they weren't paying close enough attention to the warning signs. Once again, a large iguana is very capable of causing incredibly severe damage by biting. If you haven't already, please read about what to do if you are bitten by an iguana on our Your Health & Safety page. Chances are, if you own an iguana, you may get bitten by it, so it's good information to know in case it does happen.

"One of my iguanas bit me twice, although he attempted to bite me literally hundreds of times throughout his lifetime. The first time he bit me, he was sitting next to me on the couch. I was watching television and spending some quality time with him. The next thing I know, I felt a sharp pain in my forearm. Why he bit me, I don't know, but I do know that if I had been paying closer attention, I could have prevented it. He was only about a year old at the time, so he only drew blood and left a tiny scar. The second time he bit me, I was asleep in bed. At the time, he was a free-roamer with complete freedom to go anywhere in the house. He climbed up on my bed and woke me up. I assumed he wanted something, so I fed him and proceeded to go back to sleep. A while later, I was suddenly jolted out of bed, because he had bit me square on the nose. He was about three years old at the time and successfully managed to send me to the hospital for an embarassing steristrip bandage that I had to wear for a few weeks, and of course, a lovely scar on my nose. Once again, I did not see the warning signs and didn't expect the unexpected, and luckily, he was only three years old, not doing as much damage as he could have as an older iguana. The hundreds of other times he attempted to bite me came after the first two, and never once did he do any physical damage, because I learned the hard way to be cautious and to always expect the unexpected. Please learn from my cautious!" - D. Baze

Totally unique body language. These are only the most common forms of body language iguanas use to communicate. After living with and caring for an iguana, you will begin to learn and see all of the other signs that will probably be very unique to your particular iguana. Iguanas have personalities to no end, and with a little bit of observation, training and a lot of patience, you'll learn how to read your iguana's body language almost well enough to speak it yourself.

Iguana Body Languageand Iguana Attitudes by Henry Lizardlover are two excellent and in-depth guides to understanding iguanas and their body language.
Interpreting Non-Breeding Iguana Behaviors by Melissa Kaplan has some more information on iguana body language and behavior.
Iguana Behavior Videos by Melissa Kaplan with videos by Steve Woodward. This page has many very good MPEG videos of iguana behavior and body language.
Sneezing by Melissa Kaplan has details about sneezing iguanas.

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