The Lesser Antillean iguana (Iguana delicatissima) is a large lizard that lives only in the Lesser Antilles in the Caribbean. It is also called the West Indian iguana or Lesser Antillean green iguana.
It spends much of its time in trees and mainly eats plants. It lives in forests, dry woodland and mangroves.
The species is critically endangered. It has disappeared from many islands where it once lived. One of its greatest threats is the introduced green iguana (Iguana iguana). Green iguanas compete with the native iguanas and can breed with them. Their offspring are called hybrids.
Name
The scientific name of the species is Iguana delicatissima.
The word iguana comes from iwana, a word used by the Taíno people of the Caribbean.
The species was first scientifically described by Austrian naturalist Josephus Nicolaus Laurenti in 1768.
Description
A young Lesser Antillean iguana in Dominica
The Lesser Antillean iguana is a large lizard with a long tail and strong legs. Its strong claws help it climb trees and rocks.
Its color is different between islands. Many are gray or green. Some have green coloring on the lower part of the body. Adult males can have pink cheeks and blue coloring around their eyes.
Males are usually larger than females. An adult male can have a body about 43cm (17in) long, not including its tail. Its tail can be about 80cm (31in) long.
Difference from the green iguana
The Lesser Antillean iguana can look similar to the green iguana, but there are several differences.
A green iguana usually has:
a large round scale below its ear; and
dark stripes on its tail.
The Lesser Antillean iguana does not normally have either of these features.
Scientists also found several smaller differences in the shape and scales of the two species.
Range and habitat
The Lesser Antillean iguana once lived on many islands in the northern Lesser Antilles.
The species lives in several kinds of habitat. These include:
dry forests;
scrub woodland;
rainforest;
forests near rivers; and
mangroves.
It can also sometimes live near farms and other places changed by people.
Food
Lesser Antillean iguanas are mainly herbivores. This means that they mostly eat plants.
They eat:
leaves;
flowers;
fruit;
seeds; and
young plant shoots.
They have been recorded eating more than 100 kinds of plants.
One plant they can eat is the manchineel tree. The tree produces chemicals that are poisonous to many other animals.
The iguanas can help spread plant seeds after eating fruit.
Reproduction
Female Lesser Antillean iguanas lay their eggs underground.
They dig tunnels in the soil and make a chamber at the end where the eggs are laid. A female can lay as many as about 30 eggs.
Several females may sometimes dig nests in the same area.
A 2024 study on Sint Eustatius found that other animals use the tunnels and chambers made by nesting iguanas. The researchers said this means that the iguanas can change the environment in ways that help other species.
Its population and range have become much smaller since Europeans began settling the Caribbean. Scientists believe it has disappeared from more than 80% of its former range.
The species is also listed in Appendix II of CITES. This means that international trade in the species is controlled.
In 2023, it was moved from Annex III to Annex II of the Specially Protected Areas and Wildlife Protocol (SPAW). This gives the species stronger protection across the Caribbean countries that are part of the agreement.
Threats
The main threats to the Lesser Antillean iguana include:
Green iguanas are not native to many islands in the Lesser Antilles. They have arrived as escaped pets, animals hidden in cargo, and in some cases by floating across the sea.
Green iguanas compete with Lesser Antillean iguanas for food and living space. More importantly, the two species can breed with each other. This produces hybrid iguanas and can slowly replace a native population.
This has already caused serious declines on several islands.
In 1995, green iguanas reached Anguilla after Hurricane Luis. They apparently crossed the sea on floating trees and other plants.
The native Lesser Antillean iguana later disappeared from the main island of Anguilla. Conservation workers moved some animals to the small island of Prickly Pear East, where there were no invasive green iguanas.
By 2025, more than 300 Lesser Antillean iguanas were living on Prickly Pear East. The population had grown from only a few dozen animals moved there during the conservation program.
Green iguanas have also reached Dominica. Some arrived with supplies brought to the island after Hurricane Maria in 2017.
Dominica is especially important because it has one of the largest remaining populations of the species.
Breeding programs
Some Lesser Antillean iguanas are kept in zoos as part of conservation breeding programs.
Breeding the iguanas in captivity has been difficult because many eggs do not develop.
In 2016, eleven young Lesser Antillean iguanas hatched at Jersey Zoo. This was an important success for the breeding program.
Conservation groups are also moving iguanas between safe islands, removing invasive green iguanas and improving checks on ships and cargo so that green iguanas do not reach the remaining populations.
12345678van den Burg, Matthijs P.; Breuil, Michel; Knapp, Charles (2018). "Iguana delicatissima". The IUCN Red List of Threatened Species. Retrieved September 8, 2026.
12Knapp, Charles R.; Grant, Tandora D.; Pasachnik, Stesha A. (November 6, 2020). "The global need to address threats from invasive alien iguanas". Animal Conservation. 24 (5): 717–719. doi:10.1111/acv.12660.
↑Coles, William (2002). "Green Iguana"(PDF). U.S. Virgin Islands Division of Fish and Wildlife. Archived from the original(PDF) on 11 December 2007. Retrieved September 8, 2026.
↑van den Burg, Matthijs P.; Meirmans, Patrick G.; van Wagensveld, Timothy P. (2018). "The Lesser Antillean Iguana (Iguana delicatissima) on St. Eustatius: Genetically Depauperate and Threatened by Ongoing Hybridization". Journal of Heredity. 109 (4): 426–437. doi:10.1093/jhered/esy008. PMID29471487.
↑van den Burg, Matthijs P.; Brisbane, Jeanelle L. K.; Knapp, Charles R. (2020). "Post-hurricane relief facilitates invasion and establishment of two invasive alien vertebrate species in the Commonwealth of Dominica, West Indies". Biological Invasions. 22 (2): 195–203. Bibcode:2020BiInv..22..195V. doi:10.1007/s10530-019-02107-5.
