# Iguana — Facts, Threats & Conservation

*Iguana iguana*

> An iguana is a large, mostly herbivorous, tree-dwelling lizard of the Americas. The familiar green iguana (Iguana iguana) reaches about 1.7 metres including its long tail, sports a spiny crest and throat dewlap, and is listed as Least Concern, though several other iguana species are endangered.

**IUCN status:** Least Concern (green iguana); other iguana species threatened  ·  **WARN range:** Central America, South America, Caribbean, North America (Florida, introduced)

## Quick facts
| Fact | Value |
| --- | --- |
| Common name | Green iguana (common iguana) |
| Scientific name | Iguana iguana |
| Type | Large arboreal lizard |
| Diet | Mostly herbivorous (leaves, flowers, fruit) |
| Length | Up to about 1.7 m including tail |
| Native range | Central and South America, Caribbean |
| Habitat | Tropical forest, often near water |
| IUCN status | Least Concern (green iguana) |
| CITES | Appendix II |
| Notable trait | Light-sensing parietal 'third eye' |

## Scientific classification
- **Kingdom:** Animalia
- **Phylum:** Chordata
- **Class:** Reptilia
- **Order:** Squamata
- **Family:** Iguanidae
- **Genus:** Iguana
- **Species:** Iguana iguana (green iguana)

## Conservation status
- **Status:** The green iguana (Iguana iguana) is assessed by the IUCN Red List as Least Concern: it is widespread, locally common and even invasive in some regions. International trade is regulated under CITES Appendix II. Importantly, this secure status applies to the green iguana specifically — several other iguana species, such as the Galapagos and Fijian iguanas, are threatened or endangered by habitat loss, invasive predators and climate change.
- **Population:** Not globally quantified; widespread and locally abundant across its native range, with additional invasive populations
- **Trend:** Stable overall for the green iguana; declining for several other threatened iguana species
- **Assessed:** Listed Least Concern on the IUCN Red List
- **CITES:** Appendix II
- Status varies sharply across the genus: the green iguana is secure, but it should not be taken as representative of all iguanas, many of which need active protection.

## Key facts: Iguana
- The green iguana (Iguana iguana) is a large, arboreal, mostly herbivorous lizard of Central and South America and the Caribbean.
- It can reach about 1.7 metres including the tail, with a spiny dorsal crest, a throat dewlap and a light-sensing parietal 'third eye'.
- The IUCN lists the green iguana as Least Concern, but it is regulated under CITES Appendix II.
- Released and escaped pets have created invasive populations in Florida, Hawaii and elsewhere.
- Many other iguanas — such as Galapagos and Fijian species — are threatened or endangered.
- Iguanas are popular but demanding pets, needing space, warmth, UVB light and a careful plant-based diet.

## What does an iguana look like and how big does it get?
The green iguana is unmistakable: a long, slender lizard with a crest of soft spines running from the neck down the back, a loose flap of skin under the chin called a dewlap, and a banded, whip-like tail that makes up roughly half its total length. Large adults reach about 1.7 metres from snout to tail-tip, with some exceptional individuals exceeding two metres; males are heavier and more ornate than females, the biggest weighing several kilograms. Colour is variable and a little misleading. Hatchlings and juveniles are bright leaf-green for camouflage, but adults shift towards grey-green, dull orange, brownish or even bluish tones depending on their population, temperature, age and breeding condition. On top of the head sits a pale scale known as the parietal eye, a primitive light-sensing organ that detects changes in brightness and overhead movement — useful for spotting circling predators — though it cannot form images like the true eyes. Large jowls and prominent round scales beside the eardrum are most developed in mature males.

## Where do iguanas live and what do they eat?
Green iguanas are native to a broad sweep of the American tropics, from southern Mexico through Central America and across much of South America to central Brazil, Paraguay and Bolivia, plus many Caribbean islands. They are strongly arboreal, favouring trees along rivers, lakes and mangroves, and are excellent swimmers — when alarmed they often drop from a branch straight into the water below and paddle away with their tails. Adults are almost entirely herbivorous, browsing the leaves, shoots, flowers and fruit of well over a hundred different plants. This leafy diet means they rely on basking in warm sunshine to raise their body temperature enough to digest food, so they spend long stretches motionless in the canopy. Beyond their native range, escaped and deliberately released pets have established free-living, invasive populations in places such as southern Florida, Hawaii, Puerto Rico and parts of Asia, where they can damage gardens, crops and infrastructure and compete with local wildlife.

## Are iguanas good pets, and which iguanas are endangered?
Green iguanas are among the most widely kept pet reptiles, which is exactly why so many end up homeless or released. They are long-lived and can grow surprisingly large, demanding a tall, spacious, warm enclosure, strong UVB lighting, high humidity and a varied, calcium-rich plant diet.

Poor husbandry commonly leads to metabolic bone disease and other health problems, and mature animals — especially males in breeding season — can become powerful and defensive. They are best suited to experienced keepers who can commit for the long term.

It is important to separate the green iguana's secure status from that of its relatives. While Iguana iguana is listed as Least Concern by the IUCN, several other iguanas are in real trouble: the Galapagos land and marine iguanas and the Fijian banded and crested iguanas, for example, are threatened by habitat loss, invasive predators and a changing climate. International trade in iguanas is regulated under CITES Appendix II.

## Explore iguana species on WARN
This hub focuses on the familiar green iguana — but readers often search for Galapagos, Caribbean or Lesser Antillean species. WARN publishes a twelve-species iguana library linked from this page covering green iguana, spiny-tailed relatives, Galapagos land and marine iguanas and more.

Each species page includes range, ecology, CITES status and honest messaging about why most iguanas are poor pets and some are strictly protected.

Released pets drive invasive populations in Florida and beyond — responsible ownership starts with understanding what you are taking on.

## Green iguana vs other iguanas
| Feature | Green iguana (Iguana iguana) | Other iguanas (e.g. Galapagos, Fijian) |
| --- | --- | --- |
| IUCN status | Least Concern | Often threatened or endangered |
| Range | Central/South America, Caribbean; invasive elsewhere | Often single islands or small areas |
| Diet | Mostly herbivorous | Herbivorous (marine iguana grazes algae) |
| Relationship with people | Common pet; invasive in places like Florida | Conservation concern, not invasive |
| Main threats | Few; locally over-abundant | Habitat loss, invasive predators, climate change |

## Iguana Species Guide
From the green iguana and lesser Antillean rock iguana to the rhinoceros iguana, desert iguana, spiny-tailed iguana and five more — explore 12 iguana species with range, behaviour, conservation status and why most iguanas are not suitable pets.

Full species library (12 guides): https://worldanimalrescuenetwork.org/wildlife-guides/iguana#breeds

- **Green Iguana:** The common pet-shop iguana — far too large and specialist for most homes. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/green-iguana
- **Lesser Antillean Iguana:** Critically endangered Caribbean species — not a pet, threatened by green iguana hybridisation. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/lesser-antillean
- **Cuban Rock Iguana:** Powerful rock iguana of the Caribbean — CITES protected and not a companion animal. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/cuban-rock
- **Rhinoceros Iguana:** Horned snout and armoured appearance — endangered rock iguana, not a pet. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/rhinoceros
- **Desert Iguana:** North American desert specialist — rarely kept and needing true desert habitat. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/desert
- **Spiny-tailed Iguana:** Black iguana and related Ctenosaura — common in range but poor pet candidates. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/spiny-tailed
- **Chuckwalla:** Stocky desert lizard that inflates in rock crevices — specialist, not a starter pet. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/chuckwalla
- **Fiji Banded Iguana:** Stunning emerald and blue bands — CITES Appendix I, zoo conservation only. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/fiji-banded
- **Grand Cayman Blue Iguana:** Powder-blue rock iguana saved by captive breeding — never a pet species. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/grand-cayman-blue
- **Black Iguana:** Common 'garrobo' of Central America — frequently eaten, occasionally kept inappropriately as pets. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/black-iguana
- **Marine Iguana:** The only seagoing lizard — dives for algae and is strictly protected wildlife. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/marine-iguana
- **Galápagos Land Iguana:** Yellow dragon of the Galápagos — strictly protected and never suitable as a pet. — https://worldanimalrescuenetwork.org/wildlife-guides/iguana/galapagos-land

## What WARN does
WARN does not run field projects specifically for green iguanas — the species is common, listed as Least Concern, and lives largely outside the five countries where our partners work. This guide is part of our free educational library, which exists to help people understand and respect wildlife. The threats that endanger rarer iguanas and other reptiles — habitat loss, the wildlife trade and a warming climate — are the same pressures bearing down on the animals our partners do protect on the ground.

If clear, science-based wildlife guides like this one are useful to you, a small gift helps us keep them free while supporting the animals our partners protect.

## Frequently asked questions: Iguana
### Are iguanas dangerous to humans?
Green iguanas are not venomous and generally prefer to flee, but large adults can defend themselves. They have many small sharp teeth, strong jaws and sharp claws, and can deliver a painful whip with the tail. Bites and scratches can cause injury and may carry Salmonella bacteria. Most problems involve stressed pets or cornered wild animals; given space, iguanas usually avoid confrontation.

### What do iguanas eat?
Adult green iguanas are almost entirely herbivorous, browsing leaves, shoots, flowers and fruit from over a hundred plant species. They do not naturally need animal protein, and a leafy, calcium-rich diet is essential for pets to avoid metabolic bone disease. Because plant food is hard to digest, iguanas bask in the sun to warm up enough for their gut bacteria to break it down.

### How big do iguanas get and how long do they live?
Green iguanas are among the largest lizards in the Americas, reaching about 1.7 metres from snout to tail-tip, with the tail forming roughly half that length; some exceptional animals top two metres. The tail alone makes them look enormous. Well-cared-for captive iguanas can live well over a decade, and sometimes around twenty years, which is part of why they are such a demanding long-term commitment.

### Why are iguanas a problem in Florida?
Green iguanas are not native to Florida. Escaped and released pets have bred into large free-living populations in the warm south of the state, where they dig burrows that undermine pavements and seawalls, strip gardens and crops, and leave droppings in pools and on patios. During rare cold snaps, chilled iguanas can become torpid and fall from trees. They are considered an invasive species there.

### Are iguanas endangered?
It depends on the species. The familiar green iguana (Iguana iguana) is listed as Least Concern by the IUCN and is locally abundant, even invasive in some regions. But several other iguanas are threatened or endangered, including the Galapagos land and marine iguanas and the banded and crested iguanas of Fiji, which face habitat loss, introduced predators and climate change. International iguana trade is regulated under CITES Appendix II.

### What is the spiky flap of skin under an iguana's chin?
That flap is called the dewlap, a fold of skin beneath the throat supported by part of the jaw. Iguanas extend it during displays — to look larger and more impressive to rivals, to court mates, and to warn off threats. It also helps with temperature regulation, since spreading it exposes more surface to absorb or release heat. Males generally have larger, more prominent dewlaps than females.

### Where can I read about individual iguana species?
WARN's iguana wildlife guide links to a twelve-species library covering the green iguana, Galapagos land and marine iguanas, spiny-tailed species and more — each with range, ecology and conservation status.

## Sources
- [Green iguana — Wikipedia](https://en.wikipedia.org/wiki/Green_iguana)
- [Iguana — Wikipedia](https://en.wikipedia.org/wiki/Iguana)
- [Iguana — Encyclopaedia Britannica](https://www.britannica.com/animal/iguana)
- [IUCN Red List](https://www.iucnredlist.org/)
- [CITES — Convention on International Trade in Endangered Species](https://cites.org/)
- [Encyclopaedia Britannica — Green Iguana](https://www.britannica.com/animal/green-iguana)

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Full guide: https://worldanimalrescuenetwork.org/wildlife-guides/iguana