Point Defiance Zoo & Aquarium

Green Iguana

(Iguana iguana)

Habitat and Distribution: Found mostly in the southern United States (as an invasive species), Mexico, Central America, and South America.

Size: Up to 6.5 feet long (including tail); up to 22 pounds. Males are larger than females.

Wild Diet: Adults are herbivorous, eating fruits, leaves, flowers, young shoots and grasses; juveniles may also eat insects, snails, and other invertebrates.

Predators: Hawks, eagles, large snakes, large mammals (including coatis, jaguars, ocelots and margays), lizards, and humans. Their eggs may also be eaten by many animals, including crocodiles and caimans.

Lifespan: About 8 years in the wild; over 20 years in zoos.

Reproduction: Green iguanas typically breed in the dry season. After a gestation of about 3 months, females lay 20-70 eggs in a burrow in the sand. Nests are up to a meter deep and may be shared with other females when nesting space is limited. Females return to the nest several times but do not guard their eggs. After a 3-4 month incubation at an ideal temperature of 88°F, the young all emerge at the same time, opening their eggs with special teeth called caruncles.

Behavior: Green iguanas are generally arboreal. During breeding season, a territorial male will flap his dewlap (skin below the chin), raise his body, bob his head up and down, and even open his mouth in a wide gape. A threatened iguana may lash an attacker with its tail or drop its tail completely to provide a distraction, an ability known as tail autotomy. The tail is also used to propel an iguana through the water while swimming. Iguanas often bask in the morning to finish digesting the previous day’s meal, eat at mid-day, and bask again in the afternoon to restart the digestion process. They move to safer areas to sleep, but these areas do not get the sunlight and warmth needed for digestion.

Conservation

IUCN Status: Not Evaluated

Green iguanas are not considered to be of any special conservation risk, though they are often caught for food and the pet trade. These threats combined with habitat loss may negatively affect their future status. Iguanas in pet stores are almost always imported as wild-caught or farmed babies from Columbia, El Salvador, Honduras, Peru, Mexico or Surinam. Domestic captive breeding efforts to produce healthy juveniles for the pet trade are rare, as the resulting offspring would cost much more than the imports. As a result, the vast majority of iguanas in the pet trade are considered cheap, throw-away pets, receiving much less than optimum care. The reality is that while iguanas may be acquired cheaply, they often require expensive veterinary treatment, and even when healthy their care and housing costs far outweigh the purchase price.

Green iguanas are listed on CITES Appendix II. Green iguana hunting and trade is closely regulated in some countries, but the species is endangered or extinct in others.

Did you know?

  • The green iguana is the largest South American lizard.
  • Although they are called green iguanas, their color can vary with mood, temperature, and health.