Cyclura cychlura figginsi
Encyclopedia
Cyclura cychlura figginsi, commonly known as the Exuma Island Iguana, is a critically endangered subspecies of Northern Bahamian Rock Iguana
that is found on the Exuma
island chain in the Bahamas
with a wild population of 1,300 animals, it is listed on the IUCN Red List
.
(Cyclura cychlura). Its generic
and specific
names (Cyclura
) and (Cychlura) are derived from the Ancient Greek
cyclos (κύκλος) meaning "circular" and ourá (οὐρά) meaning "tail", after the thick-ringed tail characteristic of all Cyclura. Its subspecific
name is a Latinized version of American biologist J.D. Figgins' last name.
. It attains a total length of close to 1 m (3.3 ft). 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.
Male Exuma Island Iguanas, like other species within the genus Cyclura
, are larger than females and have more prominent dorsal
crests in addition to femoral pore
s on their thighs, which are used to release pheromone
s. Females have smaller pores and have shorter crests than the males making the animals sexually dimorphic
.
island chain of the Bahamas
: 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 translocated to Pasture Cay in 2002. The Exuma Island iguana utilizes a variety of habitats from sand
y beaches and xeric limestone
devoid of vegetation to dry forests
. The iguanas use limestone crevices or sand burrows for retreats at night and in adverse weather conditions.
; they display neither territorial nor hierarchical behavior. Adult iguanas have been observed basking in large groups without showing any signs of aggression toward one another. Scientists such as W.M. Carey believe 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.
species is primarily herbivorous
, consuming leaves
, flower
s, berries
, and fruits from over 100 different plant species. Favored food plants include Seaside Rock Shrub (Rachicallis americana), Darling Plum (Reynosia
septentrionalis), Pride of Big Pine (Strumpfia
maritima), Joewood (Jacquinia
keyensis), Black Torch (Erithalis
fruticosa), Seagrape (Coccoloba uvifera
), Silver Thatch Palm (Coccothrinax argentata
), White Stopper (Eugenia
axillaris), Bay Cedar (Suriana maritima), and the rotting fruit of Seven-year Apple (Casasia
clusiifolia). A study in 2000 by Dr Allison Alberts of the San Diego Zoo
revealed that seed
s passing through the digestive tracts of Cycluras germinate
more rapidly than those that do not. This is an adaptive advantage because it allows the seeds to sprout before the end of very short rainy seasons. The Exuma Island Iguana is also an important means of distributing
these seeds to new areas (particularly when females migrate to their nesting areas) and, as the largest native herbivores of their island's ecosystem
, they are essential for maintaining the balance between climate and vegetation. They actively forage
for the feces
of the Zenaida Dove
(Zenaida aurita) and
White-crowned Pigeon
(Patagioenas leucocephala). The longevity record in captivity for an Exuma Island Iguana is twenty-three years, six months.
men were found guilty of smuggling
protected reptile species into the US, including the Exuma Island Iguana, White Cay Iguana
, and the Lesser Antillean Iguana
. Feral pigs pose a threat to the Exuma Island Iguanas, as they dig up eggs from iguana nests and feral dog
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.
has allowed volunteers to help survey populations of Exuma Island Iguanas as a form of ecotourism
. Shedd maintains an in situ
as well as an ex situ captive breeding program in order to aid the recovery of Exuma Island Iguanas. In 2002, Shedd Aquarium translocated sixteen Exuma Island Iguanas to the Exuma Cays Land and Sea Park in an effort to establish the species in a protected area.
The Bahamian Government sponsors no official captive breeding or conservation program for the Exuma Island Iguana.
Northern Bahamian Rock Iguana
The Northern Bahamian Rock Iguana is a species of lizard of the genus Cyclura that is found on the Andros and Exuma islands in the Bahamas...
that is found on the Exuma
Exuma
Exuma is a district of the Bahamas, consisting of over 360 islands . The largest of the cays is Great Exuma, which is 37 mi in length and joined to another island, Little Exuma by a small bridge. The capital and largest city in the district is George Town , founded 1793 and located on Great...
island chain in the Bahamas
The Bahamas
The Bahamas , officially the Commonwealth of the Bahamas, is a nation consisting of 29 islands, 661 cays, and 2,387 islets . It is located in the Atlantic Ocean north of Cuba and Hispaniola , northwest of the Turks and Caicos Islands, and southeast of the United States...
with a wild population of 1,300 animals, it is listed on the IUCN Red List
IUCN Red List
The IUCN Red List of Threatened Species , founded in 1963, is the world's most comprehensive inventory of the global conservation status of biological species. The International Union for Conservation of Nature is the world's main authority on the conservation status of species...
.
Taxonomy
The Exuma Island iguana, Cyclura cychlura figginsi, is endemic to the Exuma Cays, it is a subspecies of the Northern Bahamian Rock IguanaNorthern Bahamian Rock Iguana
The Northern Bahamian Rock Iguana is a species of lizard of the genus Cyclura that is found on the Andros and Exuma islands in the Bahamas...
(Cyclura cychlura). 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...
and 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...
names (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...
) and (Cychlura) are 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 subspecific
Subspecies
Subspecies in biological classification, is either a taxonomic rank subordinate to species, ora taxonomic unit in that rank . A subspecies cannot be recognized in isolation: a species will either be recognized as having no subspecies at all or two or more, never just one...
name is a Latinized version of American biologist J.D. Figgins' last name.
Anatomy and morphology
The Exuma Island Iguana is the smallest of the three subspecies of C. CychluraNorthern Bahamian Rock Iguana
The Northern Bahamian Rock Iguana is a species of lizard of the genus Cyclura that is found on the Andros and Exuma islands in the Bahamas...
. It attains a total length of close to 1 m (3.3 ft). 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.
Male Exuma Island Iguanas, like other species within 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...
, are larger than females and have more prominent 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 in addition to 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, which are used to release pheromone
Pheromone
A pheromone is a secreted or excreted chemical factor that triggers a social response in members of the same species. Pheromones are chemicals capable of acting outside the body of the secreting individual to impact the behavior of the receiving individual...
s. Females have smaller pores and have shorter crests than the males 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
This subspecies is found on at least seven small cays throughout the central and southern ExumaExuma
Exuma is a district of the Bahamas, consisting of over 360 islands . The largest of the cays is Great Exuma, which is 37 mi in length and joined to another island, Little Exuma by a small bridge. The capital and largest city in the district is George Town , founded 1793 and located on Great...
island chain of the Bahamas
The Bahamas
The Bahamas , officially the Commonwealth of the Bahamas, is a nation consisting of 29 islands, 661 cays, and 2,387 islets . It is located in the Atlantic Ocean north of Cuba and Hispaniola , northwest of the Turks and Caicos Islands, and southeast of the United States...
: 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 translocated to Pasture Cay in 2002. The Exuma Island iguana utilizes a variety of habitats from sand
Sand
Sand is a naturally occurring granular material composed of finely divided rock and mineral particles.The composition of sand is highly variable, depending on the local rock sources and conditions, but the most common constituent of sand in inland continental settings and non-tropical coastal...
y beaches and xeric limestone
Limestone
Limestone is a sedimentary rock composed largely of the minerals calcite and aragonite, which are different crystal forms of calcium carbonate . Many limestones are composed from skeletal fragments of marine organisms such as coral or foraminifera....
devoid of vegetation to dry forests
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 Bahama, where they are known as coppices...
. The iguanas use limestone crevices or sand burrows for retreats at night and in adverse weather conditions.
Behavior
Exuma Island Iguanas exhibit an unusual social system for the genus CycluraCyclura
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...
; they display neither territorial nor hierarchical behavior. Adult iguanas have been observed basking in large groups without showing any signs of aggression toward one another. Scientists such as W.M. Carey believe 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.
Diet and longevity
The Exuma Island Iguana, like most CycluraCyclura
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...
species is primarily herbivorous
Herbivore
Herbivores are organisms that are anatomically and physiologically adapted to eat plant-based foods. Herbivory is a form of consumption in which an organism principally eats autotrophs such as plants, algae and photosynthesizing bacteria. More generally, organisms that feed on autotrophs in...
, consuming leaves
Leaf
A leaf is an organ of a vascular plant, as defined in botanical terms, and in particular in plant morphology. Foliage is a mass noun that refers to leaves as a feature of plants....
, flower
Flower
A flower, sometimes known as a bloom or blossom, is the reproductive structure found in flowering plants . The biological function of a flower is to effect reproduction, usually by providing a mechanism for the union of sperm with eggs...
s, berries
Berry
The botanical definition of a berry is a fleshy fruit produced from a single ovary. Grapes are an example. The berry is the most common type of fleshy fruit in which the entire ovary wall ripens into an edible pericarp. They may have one or more carpels with a thin covering and fleshy interiors....
, and fruits from over 100 different plant species. Favored food plants include Seaside Rock Shrub (Rachicallis americana), Darling Plum (Reynosia
Reynosia
Reynosia is a genus of plant in family Rhamnaceae.Species include:* Reynosia jamaicensis, M.C. Johnston...
septentrionalis), Pride of Big Pine (Strumpfia
Strumpfia
Strumpfia is a genus of flowering plants in the family Rubiaceae. It is monospecific and indigenous to the West Indies. It is an evergreen shrub of coastal areas that rarely exceeds in height....
maritima), Joewood (Jacquinia
Jacquinia
Jacquinia is a genus of evergreen shrubs and trees in the family Theophrastaceae, native to Central America and the Caribbean.The genus was established by Linnaeus in 1760 and named by him in honor of Jacquin.There are about 86 species. ....
keyensis), Black Torch (Erithalis
Erithalis
Erithalis is a genus of flowering plants in the coffee family, Rubiaceae. It contains the following species :* Erithalis harrisii Urb.* Erithalis quadrangularis Krug & Urb....
fruticosa), Seagrape (Coccoloba uvifera
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, Barbados and Bermuda...
), Silver Thatch Palm (Coccothrinax argentata
Coccothrinax argentata
Coccothrinax argentata is a palm which is native to Bahamas, south Florida southeast Mexico and San Andrés Island. It is a small , slow-growing fan palm with leaves that are dark blue-green above and silver-coloured below. Flowers are white and small on light orange branches. The fruits rae...
), White Stopper (Eugenia
Eugenia
Eugenia is a genus of flowering plants in the myrtle family Myrtaceae. It has a worldwide, although highly uneven, distribution in tropical and subtropical regions. The bulk of the approximately 1,000 species occur in the New World tropics, especially in the northern Andes, the Caribbean, and the...
axillaris), Bay Cedar (Suriana maritima), and the rotting fruit of Seven-year Apple (Casasia
Casasia
Casasia is a flowering plant genus in the family Rubiaceae. These shrubs or small trees occur on the Caribbean islands and in one case in Florida.Some of the ten accepted species were formerly placed elsewhere, e.g...
clusiifolia). A study in 2000 by Dr Allison Alberts of 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...
revealed that seed
Seed
A seed is a small embryonic plant enclosed in a covering called the seed coat, usually with some stored food. It is the product of the ripened ovule of gymnosperm and angiosperm plants which occurs after fertilization and some growth within the mother plant...
s passing through the digestive tracts of Cycluras germinate
Germination
Germination is the process in which a plant or fungus emerges from a seed or spore, respectively, and begins growth. The most common example of germination is the sprouting of a seedling from a seed of an angiosperm or gymnosperm. However the growth of a sporeling from a spore, for example the...
more rapidly than those that do not. This is an adaptive advantage because it allows the seeds to sprout before the end of very short rainy seasons. The Exuma Island Iguana is also an important means of distributing
Seed dispersal
Seed dispersal is the movement or transport of seeds away from the parent plant. Plants have limited mobility and consequently rely upon a variety of dispersal vectors to transport their propagules, including both abiotic and biotic vectors. Seeds can be dispersed away from the parent plant...
these seeds to new areas (particularly when females migrate to their nesting areas) and, as the largest native herbivores of their island's ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
, they are essential for maintaining the balance between climate and vegetation. They actively forage
Coprophagia
Coprophagia or coprophagy is the consumption of feces, from the Greek κόπρος copros and φαγεῖν phagein . Many animal species practice coprophagia as a matter of course; other species do not normally consume feces but may do so under unusual conditions...
for the feces
Feces
Feces, faeces, or fæces is a waste product from an animal's digestive tract expelled through the anus or cloaca during defecation.-Etymology:...
of the Zenaida Dove
Zenaida Dove
The Zenaida Dove is a member of the bird family Columbidae, which includes doves and pigeons. It is the national bird of Anguilla, where it is commonly referred to as a Turtle Dove. It lays two white eggs on a flimsy platform built on a tree or shrub. It also nests in rock crevices and on grassy...
(Zenaida aurita) and
White-crowned Pigeon
White-crowned Pigeon
The White-crowned Pigeon is a species of bird in the family Columbidae . It inhabits the northern and central Caribbean islands and some places on the North and Central American mainland...
(Patagioenas leucocephala). The longevity record in captivity for an Exuma Island Iguana is twenty-three years, six months.
Mating
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.Endangered status
It is estimated that the current population size is less than 1,300 animals and has 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 caused by a tourist's cigarette was reported on an iguana-inhabited island. In 1999, two FloridaFlorida
Florida is a state in the southeastern United States, located on the nation's Atlantic and Gulf coasts. It is bordered to the west by the Gulf of Mexico, to the north by Alabama and Georgia and to the east by the Atlantic Ocean. With a population of 18,801,310 as measured by the 2010 census, it...
men were found guilty of smuggling
Smuggling
Smuggling is the clandestine transportation of goods or persons, such as out of a building, into a prison, or across an international border, in violation of applicable laws or other regulations.There are various motivations to smuggle...
protected reptile species into the US, including the Exuma Island Iguana, White Cay Iguana
Cyclura rileyi
Cyclura rileyi, commonly known as the San Salvador Rock Iguana or Bahamian Rock Iguana, is a critically endangered species of lizard of the genus Cyclura native to three island groups in the Bahamas. The species is in decline due to habitat encroachment by human development and predation by feral...
, and the Lesser Antillean Iguana
Lesser Antillean Iguana
The Lesser Antillean Iguana is a large arboreal lizard endemic to the Lesser Antilles. It is one of two species of lizard of the genus Iguana and is in severe decline due to habitat destruction, feral predators, hunting, and hybridization with its sister species the Green iguana...
. Feral pigs pose a threat to the Exuma Island Iguanas, as they dig up eggs from iguana nests and feral dog
Dog
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 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 AquariumShedd Aquarium
The John G. Shedd Aquarium is an indoor public aquarium in Chicago, Illinois in the United States that opened on May 30, 1930. The aquarium contains over 25,000 fish, and was for some time the largest indoor aquarium in the world with of water. The Shedd Aquarium was the first inland aquarium with...
has allowed volunteers to help survey populations of Exuma Island Iguanas as a form of ecotourism
Ecotourism
Ecotourism is a form of tourism visiting fragile, pristine, and usually protected areas, intended as a low impact and often small scale alternative to standard commercial tourism...
. Shedd maintains an in situ
In situ
In situ is a Latin phrase which translated literally as 'In position'. It is used in many different contexts.-Aerospace:In the aerospace industry, equipment on board aircraft must be tested in situ, or in place, to confirm everything functions properly as a system. Individually, each piece may...
as well as an ex situ captive breeding program in order to aid the recovery of Exuma Island Iguanas. In 2002, Shedd Aquarium translocated sixteen Exuma Island Iguanas to the Exuma Cays Land and Sea Park in an effort to establish the species in a protected area.
The Bahamian Government sponsors no official captive breeding or conservation program for the Exuma Island Iguana.