Do Iguanas Change Color & Why?

do iguanas change color

If you’re new to the iguana world, you may be wondering whether these large beautiful lizards change color. The answer is yes, but probably not how you think they do.

As a general rule, iguanas will change colors for various reasons, such as stress, temperature change, and/or sickness. Most color changes are perfectly normal, and do not require medical attention. Darkening of the skin due to disease, on the other-hand, must be addressed immediately.

If you plan on owning an iguana or already do and want to know what colors they may turn into and why, stick around as I’m going to explain everything you need to know as simple as possible.

Do Iguanas Change Color?

Yes, iguanas do change color, but not at will or for the reasons you may think. Iguanas typically change color because of health issues or environmental changes – not for camouflage.

These subtle color changes are often a result of physiological thermoregulation, which is the iguana’s response to temperature changes.

However, an iguana’s skin can also change color for a variety of other reasons, such as breeding, stress or illness.

5 Reasons Why Iguanas Change Color

Example of iguana changing colors

Iguanas can change colors for many reasons. Some color changes may indicate a health issue, stress or anxiety, and others can be due to temperature, breeding season or more. The following are the most common reasons why iguanas change colors:

1. The Iguana is Responding to Temperature (Darker or Lighter)

An iguana’s color is also influenced by its environment. Like most reptiles, iguanas are cold-blooded. Their color changes are often related to being too hot or cold.

  • If temperatures are especially cold, iguanas may become darker to take in more sunlight and heat. Green iguanas, for example, become a dark green color.
  • Some cold iguanas also develop dark wavy lines on their heads and bodies.
  • If an iguana gets too hot, it may shift to a lighter color to cool off. Green or tan-colored iguanas may turn a very pale green or cream color.

Color changes are one of the main ways iguanas and other reptiles regulate their body temperatures and adapt to their environment.

Iguanas start to become lethargic and sluggish once temperatures fall below 50 degrees. Often, they will change colors before reaching this point.

2. The Iguana is Stressed (Black or Dull)

No living creature is immune to stress – not even the iguana. When these reptiles feel anxious, fearful or tense, they shift to a darker, duller or even black color.

These color changes can happen within just minutes of feeling stressed.

But what causes an iguana to feel stressed out?

  • Environmental changes, like a new cage or even a home renovation. Your iguana may even feel stressed if you change your clothes or try out a new hairstyle.
  • Inappropriate cage sizes. Baby iguanas can get stressed out by cages that are too big. On the other hand, adult iguanas get seriously stressed out by cages that are too small.
  • Other iguanas. Having other iguanas in the home or in the same cage can be stressful, especially if you have two or more males. Rivalries between male iguanas can be extreme.
  • Routine changes. Iguanas love their routines. They prefer to eat and sleep at the same time every day. Any changes to their routine can stress them out.
  • Pets and people. Iguanas are often fearful of new people and pets in the home.
  • Bright colors or unusual shapes. Some iguanas are afraid of bright colors, like yellow or purple. They can also become fearful of unusually shaped toys and objects.

Iguanas can be very sensitive to change, but they learn to adapt quickly and get used to their new environment.

If you just brought your new iguana home and its color has become darker or duller, it’s likely stressed by all of the changes it’s experiencing. Be patient and keep an eye out.

If your iguana doesn’t change back to its usual color, its darker skin may be a sign that it’s sick or injured.

Changes in eating and drinking habits may also signify that it’s time to take your iguana to the vet.

Not sure how to tell if your iguana is stressed? Check out this post I wrote titled, “15 Signs Your Iguana is Stressed & What to do About it.

3. The Iguana Feels Threatened (Dark Brown or Gray)

Although they live in small groups in the wild, iguanas are generally not social animals. They may feel threatened by other iguanas or even other people.

When they feel threatened, iguanas may extend their dewlaps and change colors. If your iguana is graying or browning, this is a sign that it’s unhappy and may be feeling threatened or stressed.

Along with color changes, threatened or aggressive iguanas may:

  • Pull in their sides to make their bodies look bigger and taller.
  • Stand on their feet.
  • Bob their heads – the quicker the bob, the more threatened they feel.
  • Hiss.
  • Lash its tail.

Iguanas can feel threatened for a variety of reasons, including all of the stress triggers listed above.

Territorial iguanas may feel threatened by simple things like stuffed toys or actual threats, like other iguanas in the home.

Regardless of the trigger, you will likely notice your iguana shift to a darker color when it feels threatened or angry.

4. The Iguana is Sick (Yellow, Pink, Dark Brown, Black and Others)

Unfortunately, iguanas are not immune to disease or sickness. If an iguana changes color, it can indicate a wide range of issues, including:

  • Fungal infection
  • Bacterial Infection
  • Internal or external parasites
  • Respiratory disease
  • Mouth rot
  • Liver Disease

Treating the condition as early on as possible will reduce potential health risks for the reptile.

A few of the sicknesses and diseases that can cause an iguana to change colors include:

Mite Infestations

Mites, especially red mites, can be found on an iguana’s belly and limbs. If an iguana is experiencing a mite infestation, its scales may blacken and become red.

Fungal Infection

Fungal infections cause a similar color change to mite infestations and will cause darker, raised areas on their skin.

Bacterial Infection

Iguanas carry many forms of bacteria – some even harmful to humans – but most will only impact the reptile. These infections have many names, such as:

  • Scale rot
  • Blister disease

If an iguana is dealing with a bacterial infection, its skin will often turn dark brown or even black.

Mouth Rot

Infectious stomatitis will lead to thickening saliva and a noticeable change in an iguana’s appetite. However, if you open their mouth, there’s often a color change in their mouth, too.

Respiratory Issues

A wide range of respiratory issues can impact iguanas, causing them to suffer from shallow breathing. While not all respiratory issues cause skin color changes, some iguanas will turn orange.

Liver Disease

Liver issues often present as a “yellowing” of the skin. However, iguana skin will become yellow before shedding. So, if it’s time for them to shed (once or twice per year), the yellowing may not be a concern.

5. It’s Breeding Season for the Iguana (Orange or Red)

Your iguana will enter breeding season during the “dry season.” The reason for breeding at this time is that babies will hatch during the wet months when food is plentiful.

However, as an owner, there’s another easy way to tell if your iguana is ready to mate: their color changes.

Your iguana will change to one of two colors:

  • Orange
  • Red

Breeding color changes can be seen all over the body, or your iguana may only experience color changes on certain parts of their body, such as on its legs or spikes.

Females may also change colors, but their change will be less intense than their male counterparts.

If an iguana is more dominant, it’s not uncommon for them to retain their orange, red or orange-reddish color change past breeding season.

Even if the iguana feels dominant over a cat or dog in your home, it may retain its new coloring.

Note: If you have multiple dry seasons or your reptile is kept indoors in a dry area all year, it will only go into breeding season once per year. Iguanas can be notoriously difficult to breed in captivity.

Do Iguanas Camouflage Like Chameleons?

Iguanas can change their colors, but they can’t camouflage themselves in the same way as a chameleon. Chameleons will rearrange the actual nanocrystals of their skin to blend into the environment.

In fact, if another male chameleon comes around and poses a threat, they will change to bold colors to be more intimidating.

Iguanas do not have this same luxury of camouflaging into the environment as well as their chameleon counterparts. However, they often naturally blend into the foliage.

So, do iguanas change color? Certainly, but most changes are natural and nothing to concern yourself with. The one time to be worried is when color changes occur due to diseases.

Skin issues, mite infestations and bacterial infections can cause an iguana to change colors and will need to be treated promptly.


Phillip is the proud founder of Scaly Pets, a website dedicated to educating reptile pet owners. As a former owner of various reptiles, Phillip not only brings well researched topics to the table, but also years of personal experience. Now, he's sharing his passion with the rest of the world.

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