Turks and Caicos rock iguana
Encyclopedia
The Turks and Caicos rock iguana (Cyclura carinata) is a critically endangered
species of lizard
of the genus Cyclura
that is endemic
to the Turks and Caicos islands. Turks and Caicos has 50,000 rock iguanas
, the healthiest population of rock iguanas in the Caribbean
.
in Fauna Americana in 1825. 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. Its specific
name carinata means "keeled" and refers to the animal's scales
. The species is endemic to 50-60 of the 200 islands and cays that make up the Turks and Caicos Islands. It has one subspecies which lives on Booby Cay, Bartsch's iguana (Cyclura carinata bartschi)
. Morphological and genetic data indicate that the closest living relative of C. carinata is C. ricordi
of Hispaniola
.
Like other members of the genus cyclura, males of this species are larger than females(in this case twice as large in body mass) and have larger dorsal
crests and femoral pore
s on their thighs making the animals sexually dimorphic
.
The Turks and Caicos rock iguana inhabits small cay
s, but has been reduced to less than 5% of its original range largely due to the introduction of predators.
2,000 iguanas are the only land creatures that inhabit Little Water Cay. To promote tourism on Little Water Cay, a boardwalk has been built throughout the island. Tourists can take a tour of the island, along this boardwalk, but are not permitted to step off it.
The Turks and Caicos rock iguana dwells in rocky areas and sandy habitats as sand is required for nesting. The Turks and Caicos iguana is diurnal and spends the night in the burrows it has dug or in natural retreats in or under the rocks.
throughout the year in order to guarantee access to food and females. Females only become territorial when defending their nest site upon laying eggs and for several weeks following. The animals mate in May, and the female lays a single clutch of two to nine eggs in June. The eggs hatch in September after a 90-day incubation period.
s and cat
s. In the 1970s a population of 15,000 iguanas was completely destroyed within five years by a mere handful of dogs and cats brought to Pine Cay
by hotel workers. Competitive grazing with domestic and feral livestock is a secondary factor.
In 2000 scientists from the San Diego Zoo
's division of Conservation and Research for Endangered Species (CRES), under the direction of Conservation Research Fellow Dr. Glenn Gerber translocated 218 iguanas from Big Ambergris and Little Water Cay where their populations were threatened to four uninhabited cays within the Turks and Caicos reserve system.
To date, these iguanas have experienced a 98 percent survival rate; they have adapted to new conditions and even successfully reproduced the immediate breeding season. Yearling iguanas resulting from the reproduction of the original translocated adults from 2002 are exceeding the size of their counterparts on the source Cays from which their ancestors were translocated by as much as 400%.
Legislation to protect the iguanas has been drafted by the Turks and Caicos government in 2003. Additionally, the National Trust for the Turks and Caicos Islands has stewardship
for the Little Water Cay to ensure that it is not mismanaged and has initiated a program to remove feral cats from Pine Cay and Water Cay.
Critically endangered
Version 2010.3 of the IUCN Red List of Threatened Species identified 3744 Critically Endangered species, subspecies and varieties, stocks and subpopulations.Critically Endangered by kingdom:*1993 Animalia*2 Fungi*1745 Plantae*4 Protista-References:...
species of lizard
Lizard
Lizards are a widespread group of squamate reptiles, with nearly 3800 species, ranging across all continents except Antarctica as well as most oceanic island chains...
of the genus Cyclura
Cyclura
Cyclura is a genus of lizards from the family Iguanidae. Members of this genus are known as "cyclurids" or more commonly as rock iguanas and only occur on islands in the West Indies...
that is endemic
Endemic (ecology)
Endemism is the ecological state of being unique to a defined geographic location, such as an island, nation or other defined zone, or habitat type; organisms that are indigenous to a place are not endemic to it if they are also found elsewhere. For example, all species of lemur are endemic to the...
to the Turks and Caicos islands. Turks and Caicos has 50,000 rock iguanas
Cyclura
Cyclura is a genus of lizards from the family Iguanidae. Members of this genus are known as "cyclurids" or more commonly as rock iguanas and only occur on islands in the West Indies...
, the healthiest population of rock iguanas in the Caribbean
Caribbean
The Caribbean is a crescent-shaped group of islands more than 2,000 miles long separating the Gulf of Mexico and the Caribbean Sea, to the west and south, from the Atlantic Ocean, to the east and north...
.
Taxonomy
The Turks and Caicos rock iguana, Cyclura carinata carinata, was first described by American Zoologist Richard HarlanRichard Harlan
Richard Harlan was an American naturalist, zoologist, physicist and paleontologist....
in Fauna Americana in 1825. Its generic
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
name (Cyclura
Cyclura
Cyclura is a genus of lizards from the family Iguanidae. Members of this genus are known as "cyclurids" or more commonly as rock iguanas and only occur on islands in the West Indies...
) is derived from the Ancient Greek
Ancient Greek
Ancient Greek is the stage of the Greek language in the periods spanning the times c. 9th–6th centuries BC, , c. 5th–4th centuries BC , and the c. 3rd century BC – 6th century AD of ancient Greece and the ancient world; being predated in the 2nd millennium BC by Mycenaean Greek...
cyclos (κύκλος) meaning "circular" and ourá (οὐρά) meaning "tail", after the thick-ringed tail characteristic of all Cyclura. Its specific
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
name carinata means "keeled" and refers to the animal's scales
Scale (zoology)
In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...
. The species is endemic to 50-60 of the 200 islands and cays that make up the Turks and Caicos Islands. It has one subspecies which lives on Booby Cay, Bartsch's iguana (Cyclura carinata bartschi)
Cyclura carinata bartschi
Bartsch's iguana or Booby Cay iguana is an endangered subspecies of lizard of the genus Cyclura endemic to a single cay, Booby Cay, in the Turks and Caicos islands.-Taxonomy:...
. Morphological and genetic data indicate that the closest living relative of C. carinata is C. ricordi
Cyclura ricordi
The Hispaniolan Ground Iguana, Ricord's Ground Iguana, Ricord's Rock Iguana, or Ricord's Iguana is a critically endangered species of rock iguana....
of Hispaniola
Hispaniola
Hispaniola is a major island in the Caribbean, containing the two sovereign states of the Dominican Republic and Haiti. The island is located between the islands of Cuba to the west and Puerto Rico to the east, within the hurricane belt...
.
Anatomy and morphology
Measuring less than 770 mm in length when full grown, the Turks and Caicos Rock iguana is one of the smallest species of Cyclura. The lizard's basic color can range from green to brownish grey, usually patterned by darker markings. The species lacks the large scales on the upper surface of its head, characteristic of other species of cyclura and possesses larger dorsal spines than other species of iguana.Like other members of the genus cyclura, males of this species are larger than females(in this case twice as large in body mass) and have larger dorsal
Dorsum (biology)
In anatomy, the dorsum is the upper side of animals that typically run, fly, or swim in a horizontal position, and the back side of animals that walk upright. In vertebrates the dorsum contains the backbone. The term dorsal refers to anatomical structures that are either situated toward or grow...
crests and femoral pore
Femoral pore
Femoral pores are a part of a holocrine secretory gland found on the inside of the thighs of certain lizards and amphisbaenians which releases pheromones to attract mates or mark territory. In certain species only the male has these pores and in other species, both sexes have them, with the males...
s on their thighs making the animals sexually dimorphic
Sexual dimorphism
Sexual dimorphism is a phenotypic difference between males and females of the same species. Examples of such differences include differences in morphology, ornamentation, and behavior.-Examples:-Ornamentation / coloration:...
.
Habitat and distribution
Cay
A cay , also spelled caye or key, is a small, low-elevation, sandy island formed on the surface of coral reefs. Cays occur in tropical environments throughout the Pacific, Atlantic and Indian Oceans , where they provide habitable and agricultural land for hundreds of thousands of people...
s, but has been reduced to less than 5% of its original range largely due to the introduction of predators.
2,000 iguanas are the only land creatures that inhabit Little Water Cay. To promote tourism on Little Water Cay, a boardwalk has been built throughout the island. Tourists can take a tour of the island, along this boardwalk, but are not permitted to step off it.
The Turks and Caicos rock iguana dwells in rocky areas and sandy habitats as sand is required for nesting. The Turks and Caicos iguana is diurnal and spends the night in the burrows it has dug or in natural retreats in or under the rocks.
Diet and longevity
Like all Cyclura species, the Turks and Caicos rock iguana is primarily herbivorous, consuming leaves, flowers, and fruits from over 58 different plant species. This diet is very rarely supplemented with insects, mollusks, crustaceans, arachnids, lizards, and carrion. It has been noted that in captivity, it eats both animal and plant food. Gerber and Iverson write that the Turks and Caicos rock iguana may live at least 20 years.Mating
Adult males are sexually mature at seven years of age and are territorialTerritory (animal)
In ethology the term territory refers to any sociographical area that an animal of a particular species consistently defends against conspecifics...
throughout the year in order to guarantee access to food and females. Females only become territorial when defending their nest site upon laying eggs and for several weeks following. The animals mate in May, and the female lays a single clutch of two to nine eggs in June. The eggs hatch in September after a 90-day incubation period.
Causes of decline
Like most Cyclura species the Turks and Caicos rock iguana is in decline. In this species' case it is primarily due to its small body size which makes it vulnerable to introduced predators such as dogDog
The domestic dog is a domesticated form of the gray wolf, a member of the Canidae family of the order Carnivora. The term is used for both feral and pet varieties. The dog may have been the first animal to be domesticated, and has been the most widely kept working, hunting, and companion animal in...
s and cat
Cat
The cat , also known as the domestic cat or housecat to distinguish it from other felids and felines, is a small, usually furry, domesticated, carnivorous mammal that is valued by humans for its companionship and for its ability to hunt vermin and household pests...
s. In the 1970s a population of 15,000 iguanas was completely destroyed within five years by a mere handful of dogs and cats brought to Pine Cay
Pine Cay
Pine Cay is an privately owned island occupied by 36 homeowners and a small exclusive resort The Meridian Club in the Turks and Caicos Islands.The Meridian Club consists of 13 beachfront hotel rooms, a restaurant, clubhouse and bar. There is also a small spa....
by hotel workers. Competitive grazing with domestic and feral livestock is a secondary factor.
Conservation measures
Although Little Water Cay is home to over 2,000 Turks and Caicos rock iguanas, they have been wiped out from the other cays in their former range. Little Water Cay is now a nature reserve and neither dogs nor cats are permitted on the island to ensure the survival of the critically endangered species.In 2000 scientists from the San Diego Zoo
San Diego Zoo
The San Diego Zoo in Balboa Park, San Diego, California, is one of the most progressive zoos in the world, with over 4,000 animals of more than 800 species...
's division of Conservation and Research for Endangered Species (CRES), under the direction of Conservation Research Fellow Dr. Glenn Gerber translocated 218 iguanas from Big Ambergris and Little Water Cay where their populations were threatened to four uninhabited cays within the Turks and Caicos reserve system.
To date, these iguanas have experienced a 98 percent survival rate; they have adapted to new conditions and even successfully reproduced the immediate breeding season. Yearling iguanas resulting from the reproduction of the original translocated adults from 2002 are exceeding the size of their counterparts on the source Cays from which their ancestors were translocated by as much as 400%.
Legislation to protect the iguanas has been drafted by the Turks and Caicos government in 2003. Additionally, the National Trust for the Turks and Caicos Islands has stewardship
Stewardship
Stewardship is an ethic that embodies responsible planning and management of resources. The concept of stewardship has been applied in diverse realms, including with respect to environment, economics, health, property, information, and religion, and is linked to the concept of sustainability...
for the Little Water Cay to ensure that it is not mismanaged and has initiated a program to remove feral cats from Pine Cay and Water Cay.