''Cyclura cychlura figginsi'', known by the
common name
In biology, a common name of a taxon or organism (also known as a vernacular name, English name, colloquial name, country name, popular name, or farmer's name) is a name that is based on the normal language of everyday life; and is often contrast ...
of guana
and sometimes called the Exuma Island iguana in the international literature, is a subspecies of the northern rock iguana,
''C. cychlura'', that is found on the
Exuma
Exuma is a district of The Bahamas, consisting of over 365 islands, also called cays.
The largest of the cays is Great Exuma, which is 37 mi (60 km) in length and joined to another island, Little Exuma, by a small bridge. The capital ...
island chain in
the Bahamas
The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the Atlantic Ocean, North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to ...
with an estimated wild population of 1,300 animals in 2004, it has been listed on the
IUCN Red List
The International Union for Conservation of Nature (IUCN) Red List of Threatened Species, also known as the IUCN Red List or Red Data Book, founded in 1964, is the world's most comprehensive inventory of the global conservation status of biol ...
as
critically endangered.
Taxonomy
''Cyclura cychlura figginsi'' is a subspecies of the northern Bahamian rock iguana, ''
Cyclura cychlura
''Cyclura'' is a genus of lizards in the family Iguanidae. Member species of this genus are commonly known as "cycluras" or more commonly as rock iguanas and only occur on islands in the West Indies. Rock iguanas have a high degree of endemism, w ...
''.
Its
subspecific name commemorates the American biologist J. D. Figgins.
In the late 19th century the American naturalist
Charles Johnson Maynard
Charles Johnson Maynard (May 6, 1845 – October 15, 1929) was an American naturalist and ornithologist born in Newton, Massachusetts. He was a collector, a taxidermist, and an expert on the vocal organs of birds. In addition to birds, he also s ...
mentioned that populations of iguanas still existed on the small island
Bitter Guana Cay
Exuma is a district of The Bahamas, consisting of over 365 islands, also called cays.
The largest of the cays is Great Exuma, which is 37 mi (60 km) in length and joined to another island, Little Exuma, by a small bridge. The capital ...
, being the namesake of the
toponym
Toponymy, toponymics, or toponomastics is the study of '' toponyms'' (proper names of places, also known as place names and geographic names), including their origins, meanings, usage and types. Toponym is the general term for a proper name of ...
, and he also mentioned that he thought it was possible this population could be named as a new species.
[ In 1923 ]Thomas Barbour
Thomas Barbour (August 19, 1884 – January 8, 1946) was an American herpetologist. From 1927 until 1946, he was director of the Harvard Museum of Comparative Zoology (MCZ) founded in 1859 by Louis Agassiz at Harvard University in Cambridge, Ma ...
obliged. In 1975 Albert Schwartz and Richard Thomas subsumed it as a subspecies
In biological classification, subspecies is a rank below species, used for populations that live in different areas and vary in size, shape, or other physical characteristics (morphology), but that can successfully interbreed. Not all species ...
of ''C. cychlura''.[ In their 1977 ]monograph
A monograph is a specialist work of writing (in contrast to reference works) or exhibition on a single subject or an aspect of a subject, often by a single author or artist, and usually on a scholarly subject.
In library cataloging, ''monograph ...
on ''Cyclura'', Schwartz and W. M. Carey explain that it is morphologically indistinguishable in squamation from other forms of ''C. cychlura''.
Description
This attains a total length of close to . Its coloration is dark-gray to black, with white or orange tinged scales on the head and snout depending upon which cay the iguana is from.
This species is sexually dimorphic
Sexual dimorphism is the condition where the sexes of the same animal and/or plant species exhibit different morphological characteristics, particularly characteristics not directly involved in reproduction. The condition occurs in most ani ...
; males are larger than females.
Distribution
''Cyclura cychlura figginsi'' is endemic
Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...
to the Exuma Cays
Exuma is a district of The Bahamas, consisting of over 365 islands, also called cays.
The largest of the cays is Great Exuma, which is 37 mi (60 km) in length and joined to another island, Little Exuma, by a small bridge. The capital ...
. This subspecies is found on at least seven small cays throughout the central and southern Exuma island chain of the Bahamas
The Bahamas (), officially the Commonwealth of The Bahamas, is an island country within the Lucayan Archipelago of the West Indies in the Atlantic Ocean, North Atlantic. It takes up 97% of the Lucayan Archipelago's land area and is home to ...
: Bitter Guana Cay, Gaulin Cay, White Bay Cay, Noddy Cay, North Adderly Cay, Leaf Cay, and Guana Cay. The entire population on Leaf Cay was transferred to Pasture Cay in 2002.
Ecology
Habitat
The iguana utilizes a variety of habitats from sandy beaches and xeric
Deserts and xeric shrublands are a biome defined by the World Wide Fund for Nature. Deserts and xeric (ancient Greek xērós, “dry") shrublands form the largest terrestrial biome, covering 19% of Earth's land surface area. Ecoregions in this h ...
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
devoid of vegetation to Bahamian dry forests
The Bahamian dry forests are a tropical and subtropical dry broadleaf forest ecoregion in the Bahamas and the Turks and Caicos Islands, covering an area of . They are found on much of the northern Bahamas, including Andros, Abaco, and Grand Bah ...
. The iguanas use limestone crevices or sand burrows for retreats at night and in adverse weather conditions.
Behaviour
Exuma Island iguanas display neither territorial nor hierarchical behaviour. Adult iguanas have been observed basking in large groups without showing any signs of aggression toward one another. Carey hypothesises that this lack of a social structure allows the population to remain dense under conditions of limited resources because hierarchical social systems on small cays retard genetic variation by restricting prime nesting sites, food supplies, and retreats to a few dominant males.[Carey, W.M. (1976). ''Iguanas of the Exumas''. ''Wildlife'' 18: 59-61.] The longevity record in captivity for an Exuma Island iguana is twenty-three years, six months.
Diet
The Exuma Island iguana, like most ''Cyclura
''Cyclura'' is a genus of lizards in the family Iguanidae. Member species of this genus are commonly known as "cycluras" or more commonly as rock iguanas and only occur on islands in the West Indies. Rock iguanas have a high degree of endemism, w ...
'' species is primarily herbivorous
A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...
, consuming leaves
A leaf (plural, : leaves) is any of the principal appendages of a vascular plant plant stem, stem, usually borne laterally aboveground and specialized for photosynthesis. Leaves are collectively called foliage, as in "autumn foliage", wh ...
, flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants (plants of the division Angiospermae). The biological function of a flower is to facilitate reproduction, usually by providing a mechani ...
s, berries
A berry is a small, pulpy, and often edible fruit. Typically, berries are juicy, rounded, brightly colored, sweet, sour or tart, and do not have a stone or pit, although many pips or seeds may be present. Common examples are strawberries, raspb ...
, and fruits from over 100 plant species. Favored food plants include seaside rock shrub ('' Rachicallis americana''), darling plum ('' Reynosia septentrionalis''), pride of big pine ('' Strumpfia maritima''), joewood (''Jacquinia keyensis
''Jacquinia keyensis'', commonly called Joewood, is a woody plant in the primrose family. It is native to the West Indies
The West Indies is a subregion of North America, surrounded by the North Atlantic Ocean and the Caribbean Sea tha ...
''), black torch (''Erithalis fruticosa
''Erithalis'' is a genus of flowering plants in the family Rubiaceae. The genus is found from southern Florida to tropical America.
Species
* '' Erithalis angustifolia'' DC.
* '' Erithalis diffusa'' Correll
* '' Erithalis fruticosa'' L.
* '' Er ...
''), seagrape (''Coccoloba uvifera
''Coccoloba uvifera'' is a species of flowering plant in the buckwheat family, Polygonaceae, that is native to coastal beaches throughout tropical America and the Caribbean, including southern Florida, the Bahamas, the Greater and Lesser Antille ...
''), silver thatch palm (''Coccothrinax argentata
''Coccothrinax argentata'', commonly called the Florida silver palm, is a species of palm tree. It is native to south Florida, southeast Mexico, Colombia and to the West Indies, where it is found in the Bahamas, the southwest Caribbean and the ...
''), white stopper ('' Eugenia axillaris''), bay cedar (''Suriana maritima
''Suriana'' is a monotypic genus of flowering plants containing only ''Suriana maritima'', which is commonly known as bay cedar. Distribution
It has a pantropical distribution and can be found on coasts in the New and Old World tropics.
Descri ...
''), and the rotting fruit of seven-year apple ('' Casasia clusiifolia''). They actively forage
Forage is a plant material (mainly plant leaves and stems) eaten by grazing livestock. Historically, the term ''forage'' has meant only plants eaten by the animals directly as pasture, crop residue, or immature cereal crops, but it is also used m ...
for the feces
Feces ( or faeces), known colloquially and in slang as poo and poop, are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relati ...
of the zenaida dove
The zenaida dove (''Zenaida aurita'') is a member of the bird family Columbidae, which includes doves and pigeons. It is the national bird of Anguilla, where it is locally referred to as "turtle dove".
Description
The Zenaida dove is approxima ...
(''Zenaida aurita'') and white-crowned pigeon
The white-crowned pigeon (''Patagioenas leucocephala'') is a fruit and seed-eating species of bird in the dove and pigeon family Columbidae. It is found primarily in the Caribbean.
John James Audubon painted these pigeons, including the waterco ...
(''Patagioenas leucocephala'').
Reproduction
Mating occurs in May, and a clutch of three eggs is usually laid in June or July, in nests excavated in the sand. Females are known to guard these nest sites until they lay their eggs, after which they abandon them.
Conservation
Endangered status
The 2004 estimate of the current wild population is less than 1,300 animals, and it was said to have declined by at least 20% over the past 50 years.
Causes of decline
As with other rock iguanas, their habitat is in rapid decline due to development for tourism. In 2004 a large-scale fire possibly caused by a tourist's cigarette was reported on an iguana-inhabited island. In 1999 two Florida
Florida is a state located in the Southeastern region of the United States. Florida is bordered to the west by the Gulf of Mexico, to the northwest by Alabama, to the north by Georgia, to the east by the Bahamas and Atlantic Ocean, and to ...
men were found guilty of smuggling
Smuggling is the illegal transportation of objects, substances, information or people, such as out of a house or buildings, into a prison, or across an international border, in violation of applicable laws or other regulations.
There are various ...
protected reptile species into the US, including the Exuma Island iguana, '' Cyclura rileyi'', and the Lesser Antillean iguana
The Lesser Antillean iguana (''Iguana delicatissima'') is a large arboreal lizard endemic to the Lesser Antilles. It is one of three species of lizard of the genus ''Iguana'' and is in severe decline due to habitat destruction, introduced feral ...
. Feral pigs
The feral pig is a domestic pig which has gone feral, meaning it lives in the wild. They are found mostly in the Americas and Australia. Razorback and wild hog are Americanisms applied to feral pigs or boar-pig hybrids.
Definition
A feral pi ...
pose a threat to the Exuma Island iguanas, as they dig up eggs from iguana nests and feral dog
The dog (''Canis familiaris'' or ''Canis lupus familiaris'') is a domesticated descendant of the wolf. Also called the domestic dog, it is derived from the extinct Pleistocene wolf, and the modern wolf is the dog's nearest living relative. Do ...
s prey upon juvenile and adult iguanas. Current population size is estimated at 1,300 and has declined by at least 20% over the past 50 years.
Recovery efforts
Like all Bahamian rock iguanas, this species is protected in the Bahamas under the Wild Animals Protection Act of 1968. Since 1995, Shedd Aquarium
Shedd Aquarium (formally the John G. Shedd Aquarium) is an indoor public aquarium in Chicago, Illinois, in the United States. Opened on May 30, 1930, the aquarium was for some time the largest indoor facility in the world. Today it holds about ...
has allowed volunteers to help survey populations of Exuma Island iguanas as a form of ecotourism
Ecotourism is a form of tourism involving responsible travel (using sustainable transport) to natural areas, conserving the environment, and improving the well-being of the local people. Its purpose may be to educate the traveler, to provide funds ...
. Shedd maintains an ''in situ
''In situ'' (; often not italicized in English) is a Latin phrase that translates literally to "on site" or "in position." It can mean "locally", "on site", "on the premises", or "in place" to describe where an event takes place and is used in ...
'' as well as an ''ex situ
Svalbard GLOBAL SEED BANK, an ''ex situ'' conservation.
''Ex situ'' conservation literally means, "off-site conservation". It is the process of protecting an endangered species, variety or breed, of plant or animal outside its natural habitat; ...
'' captive breeding program in order to breed this taxon. In 2002, Shedd Aquarium translocated sixteen iguanas to the Exuma Cays Land and Sea Park in an effort to establish the species in a protected area.
The Bahamian Government has no official captive breeding or conservation program for the Exuma Island iguana.
References
External links
Entry at Cyclura.com
{{DEFAULTSORT:Cyclura Cychlura Figginsi
cychlura figginsi
Endemic fauna of the Bahamas
Reptiles of the Bahamas
Critically endangered fauna of North America