Do you know the iguana, a large lizard that looks like a dinosaur that lives mainly in South America?
Since they have appeared on TV programs and SNS and are bred in zoos, many people may have seen them.
While iguanas are popular as pets, they are often abandoned because they can no longer be tamed.
Let’s find out together what characteristics and secrets iguanas have in this article!



~ Basic information. ~


Green iguana.
Length:90~120cm(The maximum is about 210 cm.)

Iguana is a term that refers to an animal (lizard) or green iguana belonging to the “family Iguanaceae”.

Since there are many types of animals classified in the iguana family, and the places where they live and what they eat are completely different depending on the type, and iguanas generally refer to “green iguanas”, this article will basically explain green iguanas.

The green iguana is one of the large lizards that lives in Mexico and other countries.

The color of the body is bright green in juveniles, but as it grows, the color fades and gradually changes from grayish brown to blackish brown.

It is characterized by mane-like scales called “crest” on the back, folds called “dewlap” under the throat, and large circular scales under the eardrum.

The breeding season of green iguanas is once a year, digging a hole in the ground and laying 10~76 eggs in one birth. Eggs hatch in about 2~3 months, and babies reach sexual maturity about 3~4 years after birth and can reproduce.




Iguana’s Q&A.

Where does the iguana get its name?

There are various theories about the origin of the name iguana, but it is thought to be derived (etymology) from the word “iwana” in the Arawak language, the language of the indigenous peoples of the United States.


Why do iguanas live there?

Green iguanas are diurnal animals that live in the waters of the rainforests of South and North America (from Mexico to Paraguay) and the West Indies, and are basically active during bright hours.

Why do green iguanas live in their current habitat? The exact reason is unknown.

However, the warm climate is a comfortable condition for green iguanas, which are “poikilotherm” that cannot regulate their body temperature by themselves.And isn’t it because there is enough food for a large green iguana to live? It is considered to be.


What do iguanas eat?

Green iguanas are herbivorous animals that feed on grass, leaves, flowers, fruits and other plant matter. While they are small, they also eat insects, but when they grow larger, they become almost complete herbivores.

At the zoo, they eat vegetables (komatsuna, cabbage, lettuce, tomatoes, etc.), fruits (bananas, apples, papayas, etc.) and wild herbs (chinese plantain, dandelion, etc.).


What kind of personality does an iguana have?

Green iguanas are basically quiet and are said to have a gentle personality.

However, there are individual differences, and some green iguanas are very timid and nervous.

It is also known that males who are in estrus become very rough and very aggressive, such as slapping their whip-like tails and biting with their large mouths open.


Is it true that iguanas are good swimmers?

It’s true.

Green iguanas are very good swimmers and jump into the water from the top of a tree when they are about to be caught by natural enemies. And it wiggles its tail, swims well, and runs away in no time.


In addition, it is known that “marine iguanas” living in the Galapagos Islands swim in the sea and can continue diving for about 10 ~ 15 minutes.

The marine iguana is an iguana that looks like a monster that has been given the very unfortunate nickname of “ugly and clunky lizard” by Darwin.

However, contrary to appearances, they have a very quiet personality and live mainly by eating seaweed that grows in the sea.


Marine iguanas, just like green iguanas, use their tails to swim as well as crocodiles. They use their long, sharp claws to cling tightly to the rocks and eat their favorite seaweed no matter how rough the waves are.

In addition, the nostrils have glands to expel salt accumulated in the body, and during the day they have a habit of sitting still on land and sunbathing to raise their body temperature, which is characteristic of living near the cold sea, but instead they cannot climb trees.

Is it true that iguanas can be eaten?

It’s true.

Green iguanas are traditionally eaten in Mexico and Central and South America, and are also known as “forest chicken meat”.

Iguana meat is low in fat and high in protein, has no peculiarities, tastes similar to chicken, and is used locally as an ingredient in tacos and burritos, as well as in various dishes such as stews and soups.

It is said that when stewed thoroughly, the meat becomes tender and the broth comes out and is delicious.


Can iguanas be kept as pets?

When breeding rare animals at home, you must follow the rules established in some countries. This time, we will introduce whether it is possible to breed iguanas at home in Japan.

First of all, it is possible to breed iguanas as pets in Japan.

Several types of iguanas are sold for pets at pet stores that handle reptiles, but the green iguana has the largest number of breeding and distribution.

Green iguanas are not difficult to obtain, and when they are babies, they are cute enough to fit in the palm of their hands, so some people buy them on impulse.

However, when the green iguana grows, it grows to a large reptile with a total length of at least 1 m and a large length of 2 m, so there is no end to the number of people who throw it away because they cannot keep it.

Green iguanas are not as easy to get used to as dogs and cats, but they are animals that can be accustomed to eating food from their hands if they are cared for and used to it with patience.

However, due to its size, it is difficult to prepare an environment for breeding, and in fact, it is also an animal with a high hurdle to keep.

When breeding green iguanas, it is better to have at least the image and preparedness of living with a large dog.


Is it true that there are wild green iguanas in Japan?

Green iguanas are reptiles and are considered to be unable to survive the winter of Japan because they are poikilotherm.

However, it is also thought that in warm areas such as Okinawa, there is a possibility that it will overwinter and become established as a wild animal.

I don’t know if they actually settle or breed, but green iguanas, which are thought to be wild, have been sighted and captured many times on Ishigaki Island in Okinawa Prefecture.

If there is a green iguana living in the Japan, it is almost certainly an individual whose pet was abandoned or escaped.

When you keep an animal, it is natural to keep it responsibly, but if you can’t keep it, take responsibility for finding the next owner no matter what the animal.

If green iguanas settle in Japan, there are concerns that they will affect Japan native plants and animals.

For this reason, green iguanas are designated as “invasive alien species requiring attention” in the Act on Prevention of Damage to Ecosystems, etc. by Specified Alien Species (Invasive Alien Species Act).


What is the lifespan of an iguana?

The life span of a green iguana is thought to be about 20 years.

However, it is difficult to raise them, and it is said that green iguanas kept as pets often cannot complete their lifespan.


What enemies does an iguana have?

It is said that the natural enemies of iguanas in the wild are mainly birds such as birds of prey.

But for iguanas, their biggest enemy is us humans.

Because some species of iguanas are caught for pets or for food, or their habitats have been destroyed and their population is declining, and some species are worried about extinction.

However, for green iguanas, there is a problem that abandoned pets that can no longer be kept breed in the wild, becoming alien species and threatening native species that originally inhabited.

Apparently, green iguanas are animals that feed on plants and lay many eggs in one laying, so it is said that their population will increase steadily when they are adapted to the environment.

Green iguanas are innocent, but in the Florida peninsula in the United States, the number of green iguanas, which are non-native species, has increased too much, and as a result, wild plants are affected, and green iguanas are being exterminated every day.

By the way, green iguanas are classified as “Annex II” under the Washington Convention as not necessarily threatening extinction, but threatening extinction if trade is not regulated.




Type of iguana.

・Marine Iguana
・Fiji Crested Iguana
・Galapagos land Iguana
・Banana Spiny Tail Iguana
・Hispaniolan Rhinoceros Iguana
・Cuban Ground Iguana
・Green Iguana
・Black Chuckwalla
・Common Chuckwalla etc.


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