A blue-gray Grand Cayman blue iguana on sandy ground. — Photo: Charles J. Sharp, CC BY-SA 4.0, via Wikimedia Commons

Grand Cayman Blue Iguana

Cyclura lewisi

A big, blue-gray rock iguana found only on Grand Cayman, the island's largest native land animal.

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About the Grand Cayman Blue Iguana

Grand Cayman blue iguanas can be more than 5 feet long and weigh over 25 pounds, making them the largest native land animals on Grand Cayman. Their skin is dusky blue to gray and turns brighter blue in the mating season. They live only on Grand Cayman Island, in dry, rocky coastal forests with cactus and in scrub woodlands. They eat mostly leaves and stems, plus fruit and flowers.^[1]

Quick facts

Scientific name: Cyclura lewisi^[1]
Size: Over 5 feet long, nose to tail.^[1]
Weight: Over 25 pounds.^[1]
Lifespan: 25 to 40 years in the wild; one lived at least 69 years in human care.^[1]
Diet: Mostly herbivore. Leaves and stems, plus fruit and flowers.^[1]
Habitat: Dry, rocky coastal forests and scrub woodlands.^[1]
Where it lives: Grand Cayman Island.^[1]
Group life: Active by day.^[1]
Babies: Up to 20 eggs that hatch after 60 to 90 days.^[1]
Conservation status: Endangered (IUCN Red List, assessed 2012).^[2]

Fun facts

It's the largest native land animal on Grand Cayman.^[1]
Blue iguanas turn brighter blue in mating season.^[1]
One blue iguana lived at least 69 years.^[1]

Vocabulary

bask: To lie in the sun to warm up.
endemic: Found naturally in only one place.
diurnal: Active mainly during the day.
herbivore: An animal that eats only plants.
endangered: A conservation label meaning a species faces a very high risk of dying out in the wild.

See it in person

Smithsonian's National ZooWashington, D.C. · Reptile Discovery CenterSee this animal on the zoo's website ↗

These zoos had this animal when we gathered our information, but animals sometimes move. Check the zoo's website or contact the zoo before you visit.

Sources

[1] Smithsonian's National Zoo & Conservation Biology Institute. “Grand Cayman blue iguana.” https://nationalzoo.si.edu/animals/grand-cayman-blue-iguana (accessed 2026-10-08)
[2] IUCN Red List of Threatened Species. “Cyclura lewisi (Grand Cayman Blue Iguana).” https://www.iucnredlist.org/species/44275/2994409 (accessed 2026-10-08)

Facts last checked 2026-10-08.

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