Acklins Ground Iguana

Taxobox


image_width = 250px
name = Acklins Ground Iguana
status =EN
regnum = Animalia
phylum = Chordata
classis = Reptilia
ordo = Squamata
familia = Iguanidae
genus = "Cyclura"
species = "C. rileyi"
subspecies = "C. r. nuchalis"
trinomial = "Cyclura rileyi nuchalis"
trinomial_authority = Barbour and Noble, 1916 The Acklins Ground Iguana or Watling Island Iguana ("Cyclura rileyi nuchalis") is an endangered subspecies of lizard of the genus "Cyclura" it is one of three subspecific forms of Cyclura rileyi in the Iguanidae family.

Taxonomy

The Acklins Ground iguana is a recognized subspecies of the San Salvador rock iguana, recognized as such since 1975.citation
last = Hollingsworth
first = Bradford D.
title = The Evolution of Iguanas: An Overview of Relationships and a Checklist od Species
work = Iguanas: Biology and Conservation
publisher = University of California Press
pages = 35-39
date = 2004
isbn = 9780520238541 ] The species is listed as endangered according to the current IUCN Red List.IUCN2006|assessors=Hayes, W.K.|year=2000|id=6047|title=Cyclura rileyi nuchalis|downloaded=25 August 2007]

Its generic name ("Cyclura") is derived from the Ancient Greek "cyclos" (κύκλος) meaning "circular" and "ourá" (οὐρά) meaning "tail", after the thick-ringed tail characteristic of all "Cyclura" iguanas.cite web | last = Sanchez | first = Alejandro | title = Family Iguanidae: Iguanas and Their Kin | work = Father Sanchez's Web Site of West Indian Natural History Diapsids I: Introduction; Lizards | publisher = Kingsnake.com | url = http://www.kingsnake.com/westindian/metazoa10.html | accessmonthday = November 26 |accessyear = 2007] Its specific name, "rileyi", is a Latinized form of the name of American biologist, Joseph Harvey Riley.Citation | title =Riley, Joseph - Biography | journal =Washington Biologists' Field Club | work="Patuxent Wildlife Research Center" |url=http://www.pwrc.usgs.gov/resshow/perry/bios/RileyJoseph.htm ] Its subspecific name,"nuchalis", is Latin for "neck" in reference to the thick scalation around the animal's neck.

Anatomy and morphology

Acklins Ground iguana strongly resembles the San Salvador Rock Iguana in color and shape. The lizard's back color can range from red, orange or yellow, to green, brown or grey, usually patterned by darker markings. The very brightest colors (red, orange or yellow) are normally only displayed by males and are more pronounced which at warmer body temperatures. Immature iguanas lack these bright colors, being either solid brown or grey with faint slightly darker stripes. What makes this iguana stand out from the other two subspecies is the scalation on its neck and head.

Like other members of the Genus "Cyclura", males of this species are larger than females and have more prominent dorsal crests in addition to femoral pores on their thighs, which are used to release pheromones. Females lack these pores and have shorter crests than the males, making the animals somewhat sexually dimorphic.cite book
last =De Vosjoli
first =Phillipe
coauthors = David Blair
title =The Green Iguana Manual
publisher =Advanced Vivarium Systems
date =1992
location =Escondido, California
isbn = 74886904040 ] citation
last = Martins
first = Emilia P.
last2 = Lacy
first2 = Kathryn
title = Behavior and Ecology of Rock Iguanas,I: Evidence for an Appeasement Display
work = Iguanas: Biology and Conservation
publisher = University of California Press
pages = 98-108
date = 2004
isbn = 9780520238541 ]

Distribution

The Acklins Ground Iguana is endemic to three small cays in the Bahamas and is described as endangered according to the current IUCN Red List.]

Natural populations of Acklins Ground Iguanas are found only on Fish Cay and North Cay in the Acklins Bight, Bahamas. They formerly inhabited Long (Fortune) Cay. An additional introduced population with five founding individuals was established on a small cay in the early 1970s.cite paper
author = Thornton, Benjamin
title = Nesting Ecology of the Endangered Acklins Bight RockIguana, Cyclura Rileyi Nuchalis, In The Bahamas
version = abstract
publisher = Andrews University
date =June 2000 ]

These two populations are made up of 12,500-18,800 individual animals.citation
last = Hayes
first = William
last2 = Carter
first2 = Ronald
last3 = Cyril
first3 = Samuel
last4 = Thornton
first4 = Benjamin
title = Conservation of an Endangered Bahamian Rock Iguana, I
work = Iguanas: Biology and Conservation
publisher = University of California Press
pages = 232-243
date = 2004
isbn = 9780520238541 ] A translocated population in the Exumas Land and Sea Park contains 300 animals and appears to be stable.

Diet

Like all "Cyclura" species the Acklins ground Iguana is primarily herbivorous, 95% of its diet is derived from consuming leaves, flowers and fruits from 7 different plant species such as wild thyme and prickly pear cactus("Opuntia stricta"). This diet is very rarely supplemented with animal matter, although a wild specimen has been recorded eating mice.

Mating

Mating occurs between May and June depending on when the dry season ends, and 2-5 eggs are usually laid within 40 days depending on the size and age of the female. Some females have been observed migrating to coastal areas on the various cays in order to build their nests in the sand, and some guard the nest site for a short period of time. The hatchlings emerge from the nests in August to early September.

Habitat

Unlike every other species of "Cyclura" the Acklins iguana is free of threats by feral predators. The cays they dwell on are remote and human populations leave the animals undisturbed. Natural predators in the form of ospreys, herons, kestrels and seagulls have minimal impact on the populations.

The Acklins Cays also have an abundance of food and vegetation compared to the cays on which other iguanas are found and this also must be considered as a factor in their success. Sea level rise may be the greatest threat these animals face in the future, as the cays lack elevation relief and a sea level rise of 1 meter over the next 100 years could cost the cays up to 50% habitat loss.

References

External links

* [http://www.cyclura.com/status/acklin.htm Entry at Cyclura.com]
* [http://www.acklins.com/AcklinsRockIguana.html Photo from Acklins.com]
* [http://www.llu.edu/llu/faculty/whayes/documents/2000_thornton_ms-thesis_nesting_ecology_cyclura_rileyi_nuchalis.pdf Benjamin Thornton's Thesis on Acklins Ground Iguanas]