Cayman Island blue iguana (Cyclura lewisi)

Description

Cayman Island blue iguana fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Cayman Island blue iguana description

Endemic to Grand Cayman, this magnificently striking blue iguana is one of the most endangered lizards on Earth ⁽⁴⁾. Indeed, at the time of its original description in 1940 the Cayman Island blue iguana was already considered to be on the brink of extinction ⁽⁵⁾. Blue iguanas normally possess a blue-grey complexion when resting ⁽⁶⁾ but are better known for the stunning azure blue they turn during the breeding season or when excited ^{(4) (6)}. The Cayman Island blue iguana is a relatively large iguana ⁽⁷⁾, with males larger than females ⁽²⁾. Previously listed as the subspecies Cyclura nubila lewisi, this iguana has recently been recognized as a full species, Cyclura lewisi ⁽¹⁾.

Also known as

Cayman Island ground iguana, Grand Cayman blue iguana, Grand Cayman iguana.

Synonyms

Cyclura nubila lewisi.

Size

Male snout-to-vent length: up to 51.5 cm ⁽²⁾

Female snout-to-vent length: up to 41.0 cm ⁽²⁾

Cayman Island blue iguana biology

Females live a solitary life, warning others to stay away from their small territory with vigorous head bobbing gestures ⁽⁴⁾. Males and females come together only to breed, and, like all Cyclura, breed annually. 1 to 22 eggs are laid depending on the female’s age and size ⁽¹⁾, and are then incubated in the nest chamber that is dug about a foot below the surface of the soil ⁽⁷⁾. Hatchlings are vulnerable to native snakes (Alsophis cantherigerus caymanus) and have a high mortality rate ⁽¹⁾.

Primarily herbivorous, these iguanas have been observed to consume 45 different plant species from 24 different families ^{(6) (7)}. When available, they also feed on fruit, and have even been seen feeding on fungus, crabs, soil, and excrement ⁽⁷⁾.

Cayman Island blue iguana range

Once ranging throughout Grand Cayman, this iguana is now found only in the High Rock-Battle Hill area to the east and south of the Queen’s Highway. The unmanaged wild population is sparse and dispersed, and estimated in 2002 at just 10 – 25 individuals ⁽¹⁾.

Cayman Island blue iguana habitat

These blue iguanas usually occupy dry evergreen thickets and bush land, as well as man-modified habitats ^{(6) (7)}. These adaptable iguanas utilize a variety of natural and semi-disturbed habitats in response to temperature needs, food, nesting, predator pressure, and human interference ⁽⁷⁾.

Cayman Island blue iguana status

The Cayman Island blue iguana is classified as Endangered (EN) on the IUCN Red List ⁽¹⁾, and listed on Appendix I of CITES ⁽³⁾.

Cayman Island blue iguana threats

Once abundant, the Cayman Island blue iguana has been quietly heading for extinction in the wild since the colonization of the West Indian islands ⁽⁴⁾. Like other iguana species this beautiful creature is subject to many human-related threats, including: destruction of habitats for farming, residential and commercial developments; road casualties; trapping or shooting by farmers, who perceive iguanas as a threat to their crops; and predation by wild and domestic cats and dogs ^{(4) (7)}. Large scale deforestation and road construction has also increased enormously in the eastern districts over the last decade, and is only expected to accelerate ⁽⁷⁾.

Cayman Island blue iguana conservation

The Cayman Island blue iguana is fully protected under local legislation, and kept out of international trade by its listing on Appendix I of the Convention on International Trade in Endangered Species (CITES) ⁽¹⁾. The National Trust for the Cayman Islands has established an integrated conservation programme incorporating research, habitat protection, captive breeding, re-introduction/restocking, and conservation education ⁽⁷⁾. These iguanas are being bred successfully in captivity and are subsequently released after two years into the Queen Elizabeth II Botanic Park and Salina Reserve ^{(1) (4)}. Blue iguana populations in this reserve are being promoted as a major ecotourism attraction, proving beneficial to both the Park and the iguanas ⁽¹⁾. It seems that the future of wild blue iguanas must rest on managed populations in protected areas, but suitable land is scarce on Grand Cayman ⁽⁴⁾. Thus, despite encouraging conservation efforts, the Cayman Island blue iguana still clings to a precarious existence ⁽⁵⁾, and more protected land must be obtained if there is any hope of securing its future in the wild ⁽⁴⁾.

View information on this species at the UNEP World Conservation Monitoring Centre.

Find out more

For further information on the Cayman Island blue iguanas see:

IUCN Iguana Specialist Group:
http://www.iucn-isg.org/index.php

Blue Iguana Recovery Program:
http://www.blueiguana.ky/

Authentication

This information is awaiting authentication by a species expert, and will be updated as soon as possible. If you are able to help please contact:
arkive@wildscreen.org.uk

Glossary

Endemic

A species or taxonomic group that is only found in one particular country or geographic area.

Herbivorous

Diet comprises only vegetable matter.

References

1. IUCN Red List (February, 2013) 
   http://www.iucnredlist.org/  
2. Cyclura.com (October, 2005)
   http://www.cyclura.com
3. CITES (October, 2005)
   http://www.cites.org
4. Blue Iguana Recovery Program (October, 2005)
   http://www.blueiguana.ky/
5. University of Michigan (October, 2005)
   http://www.umich.edu/~esupdate/library/96.07-08/hudson.html
6. Central Florida Zoo (October, 2005)
   http://www.centralfloridazoo.org
7. IUCN Iguana Specialist Group (October, 2005)
   http://www.iucn-isg.org/index.php