Utila iguana
Encyclopedia
Ctenosaura bakeri, also known as the Utila iguana, Baker's spinytail iguana, Swamper or Wishiwilly del Suampo, is a critically endangered
species of spinytail iguana
endemic
to the island of Utila
, one of the Islas de la Bahía off the coast of Honduras
.
The Utila iguana is the only species of iguana
and one of only two species of lizard
to exclusively inhabit brackish mangrove swamps, forced there due to competition from larger species. It is the smallest of the three species of iguana found on Utila, and unique among Spiny-tailed iguana
s as it is born a dark color as opposed to bright green or yellow. It is arboreal and primarily herbivorous, although it can be an opportunistic carnivore
. Males may grow up to 76 centimetres (29.9 in) in length, while females are smaller, with a length of up to 56 centimetres (22 in). Eggs are laid in sandy beaches and hatch about 60-76 days later, with the hatchlings returning to live in the mangrove forests.
Brought to the brink of extinction by the 1990s due to hunting, it was brought back to international attention by German herpetologist Dr. Gunther Köhler and his book Reptiles of Central America. Although several zoos and wildlife associations have instituted programs for the iguanas on Utila, the species still finds itself threatened due to overhunting and may face more of a threat in the form of habitat loss. Extreme conservation efforts are in place to try to prevent this species from going extinct.
zoologist
Leonhard Hess Stejneger
in 1901, while working for the Smithsonian Institution
. The generic
name, Ctenosaura, is derived from two Greek
words: cteno (Κτενός), meaning "comb" (referring to the comblike spines on the lizard's back and tail), and saura (σαύρα), meaning "lizard". Its specific name is the Latin
ized form of the Stejneger's friend and colleague Frank Baker, who was a former director of the National Zoo in Washington DC.
The species is believed to have evolved from mainland-based ancestors, and may share ancestors with C. melanosterna and C. palearis, as it is phylogenetically closer to these two than it is to C. similis
. Access to Utila may have involved over-water dispersal during hurricanes, as is known for Iguana iguana in the Lesser Antilles
or a land bridge
to the mainland lost during the close of the last ice age
.
, an island off the northern Honduras
coast, Ctenosaura bakeri is an inhabitant of 8 square kilometres (3.1 sq mi) of mangrove forests. Unique among iguanids
and rare among reptiles, it is believed that C. bakeri was pushed into the mangrove swamps due to competition from the larger, more aggressive C. similis
, which typically inhabits the drier habitats on Utila. It has interbred with this very species and produced viable offspring. From evolutionary and ecological perspectives, inhabiting brackish mangrove forests entails very specific adaptations of diet, behavior, and resource utilization. It is one of only two known species of lizard, the other being a species of Anole
, Norops utilensis, that lives solely in mangrove forests.
Males achieve a maximum length of 76 centimetres (29.9 in), while females are typically 30% smaller at 56 centimetres (22 in). Males have a small dewlap and a dorsal crest made up of 56 large dorsal spines, making the animal sexually dimorphic
. This dorsal crest consists of white and black spines arranged in alternating groups of two or three of the same color.
s, leaves, stems, and fruit
, but they will opportunistically eat smaller animals, eggs, and arthropod
s that inhabit the mangroves. It has been observed eating smaller green iguana
s (Iguana iguana) and geckos such as Hemidactylus frenatus.
for the first year of their lives. As the Utila iguana cannot successfully lay its eggs in the mangrove swamps, the gravid females are forced to migrate to nearby sandy beaches in order to bury their clutches of eggs so they can incubate in the hot sun. After digging their nest burrows and laying their eggs, the females abandon the nests and return to the mangroves. Sixty to seventy-four days later the hatchlings emerge and move back to the swamps.
The hatchlings are 15 centimetres (5.9 in) long, the body length being a mere 3 centimetres (1.2 in) with the tail accounting for 12 centimetres (4.7 in) of its total length. The hatchlings' dark skin color enables them to blend in with the dark floor of the mangrove forests to help elude predators.
, the Senckenberg Nature Research Society
, AFE-COHDEFOR (State Forestry Administration-Honduran Forestry Development Corporation), BICA (Bay Islands Conservation Association)
and the National Autonomous University of Honduras
.
This species currently has an estimated wild population of 10,000 animals in 2-3 subpopulations, but is greatly threatened by loss of habitat, as mangrove forests are being used as garbage dump sites and deforested for the construction of homes, resorts, and marina
s. Beach habitat is being lost as natural vegetation is removed in preparation for hotel and road construction. According to a survey conducted by the IUCN, exotic invasive plants cover the ground near the mangroves and make the area inappropriate for nesting sites. The iguana is locally hunted for meat, although efforts to educate locals have helped reduce this somewhat in recent years.
In 2004, as a result of Köhler's expedition and subsequent book, Reptiles of Central America, the Conservation Project of the Utila Iguana (CPUI) was founded. The International Iguana Society and the CPUI have sought to purchase land to preserve habitats for the iguanas and plan to establish an outpost manned by Iguana Research and Breeding station personnel, who will aid in monitoring the property and work with developers to select building sites that preserve as much undisturbed beach area as possible.
The Iguana Research and Breeding station employs a "head-starting" program for newly hatched iguanas. "Head-starting", originally used to protect hatchling sea turtles, is a process by which iguana eggs are hatched in an incubator and the animals are protected and fed for the first 20 months of their lives. In the case of the Utila iguana, 50% of the animals hatched at the Center are maintained for the head-start program and the rest are released into mangrove forests after hatching. The purpose is to get the animals to a size where they are more capable of fleeing from or fighting off predators. The program has proven successful, as the iguanas behave like their wild-born counterparts. The success of the Utila program serves as a blueprint for other such programs in the Caribbean, particularly with Cyclura
species such as the Cuban Iguana and Blue Iguana
.
), each institution serving as an ex-situ
breeding center. In September, 2007, the London Zoo
successfully managed to breed Ctenosaura bakeri for the first time outside of Utila, an important step to ensure their survival if the species is lost from its natural habitat by hurricanes or over-hunting. The population is currently stable, but future declines are expected as a result of the threats mentioned above.
According to the International Species Information System
, the following zoological parks maintain Ctenosaura bakeri in their exhibits.
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 spinytail iguana
Ctenosaura
Ctenosaura is a genus of lizard commonly known as spinytail iguanas. The genus is part of the large lizard family, Iguanidae and is native to Mexico and Central America. The species range in size from about 5 inches to well over one meter. The distinctive feature of this genus is presence of the...
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 island of Utila
Útila
Utila is the third largest of Honduras' Bay Islands, after Roatán and Guanaja, in a region that marks the south end of the Mesoamerican Barrier Reef System, the second-largest in the world...
, one of the Islas de la Bahía off the coast of Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
.
The Utila iguana is the only species of iguana
Iguanidae
Iguanidae is a family of lizards, composed of iguanas and related species.-Classification of Iguanidae:Two different classification schemes have been used to define the structure of this family. These are the "traditional" classification and the classification presented by Frost et al. .Frost et...
and one of only two 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...
to exclusively inhabit brackish mangrove swamps, forced there due to competition from larger species. It is the smallest of the three species of iguana found on Utila, and unique among Spiny-tailed iguana
Ctenosaura
Ctenosaura is a genus of lizard commonly known as spinytail iguanas. The genus is part of the large lizard family, Iguanidae and is native to Mexico and Central America. The species range in size from about 5 inches to well over one meter. The distinctive feature of this genus is presence of the...
s as it is born a dark color as opposed to bright green or yellow. It is arboreal and primarily herbivorous, although it can be an opportunistic carnivore
Carnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...
. Males may grow up to 76 centimetres (29.9 in) in length, while females are smaller, with a length of up to 56 centimetres (22 in). Eggs are laid in sandy beaches and hatch about 60-76 days later, with the hatchlings returning to live in the mangrove forests.
Brought to the brink of extinction by the 1990s due to hunting, it was brought back to international attention by German herpetologist Dr. Gunther Köhler and his book Reptiles of Central America. Although several zoos and wildlife associations have instituted programs for the iguanas on Utila, the species still finds itself threatened due to overhunting and may face more of a threat in the form of habitat loss. Extreme conservation efforts are in place to try to prevent this species from going extinct.
Taxonomy
Ctenosaura bakeri was first described by NorwegianNorway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
zoologist
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...
Leonhard Hess Stejneger
Leonhard Hess Stejneger
Leonhard Hess Stejneger was a Norwegian-born American ornithologist, herpetologist and zoologist. Stejneger specialized in vertebrate natural history studies. He gained his greatest reputation with reptiles and amphibians....
in 1901, while working for the Smithsonian Institution
Smithsonian Institution
The Smithsonian Institution is an educational and research institute and associated museum complex, administered and funded by the government of the United States and by funds from its endowment, contributions, and profits from its retail operations, concessions, licensing activities, and magazines...
. The 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, Ctenosaura, is derived from two 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...
words: cteno (Κτενός), meaning "comb" (referring to the comblike spines on the lizard's back and tail), and saura (σαύρα), meaning "lizard". Its specific name is the Latin
Latin
Latin is an Italic language originally spoken in Latium and Ancient Rome. It, along with most European languages, is a descendant of the ancient Proto-Indo-European language. Although it is considered a dead language, a number of scholars and members of the Christian clergy speak it fluently, and...
ized form of the Stejneger's friend and colleague Frank Baker, who was a former director of the National Zoo in Washington DC.
The species is believed to have evolved from mainland-based ancestors, and may share ancestors with C. melanosterna and C. palearis, as it is phylogenetically closer to these two than it is to C. similis
Ctenosaura similis
The Black Spiny-tailed Iguana, Black Iguana, or Black Ctenosaur is a lizard native to Mexico and Central America that has been introduced to the United States in the state of Florida...
. Access to Utila may have involved over-water dispersal during hurricanes, as is known for Iguana iguana in the Lesser Antilles
Lesser Antilles
The Lesser Antilles are a long, partly volcanic island arc in the Western Hemisphere. Most of its islands form the eastern boundary of the Caribbean Sea with the Atlantic Ocean, with the remainder located in the southern Caribbean just north of South America...
or a land bridge
Land bridge
A land bridge, in biogeography, is an isthmus or wider land connection between otherwise separate areas, over which animals and plants are able to cross and colonise new lands...
to the mainland lost during the close of the last ice age
Ice age
An ice age or, more precisely, glacial age, is a generic geological period of long-term reduction in the temperature of the Earth's surface and atmosphere, resulting in the presence or expansion of continental ice sheets, polar ice sheets and alpine glaciers...
.
Distribution and habitat
Endemic to UtilaÚtila
Utila is the third largest of Honduras' Bay Islands, after Roatán and Guanaja, in a region that marks the south end of the Mesoamerican Barrier Reef System, the second-largest in the world...
, an island off the northern Honduras
Honduras
Honduras is a republic in Central America. It was previously known as Spanish Honduras to differentiate it from British Honduras, which became the modern-day state of Belize...
coast, Ctenosaura bakeri is an inhabitant of 8 square kilometres (3.1 sq mi) of mangrove forests. Unique among iguanids
Iguanidae
Iguanidae is a family of lizards, composed of iguanas and related species.-Classification of Iguanidae:Two different classification schemes have been used to define the structure of this family. These are the "traditional" classification and the classification presented by Frost et al. .Frost et...
and rare among reptiles, it is believed that C. bakeri was pushed into the mangrove swamps due to competition from the larger, more aggressive C. similis
Ctenosaura similis
The Black Spiny-tailed Iguana, Black Iguana, or Black Ctenosaur is a lizard native to Mexico and Central America that has been introduced to the United States in the state of Florida...
, which typically inhabits the drier habitats on Utila. It has interbred with this very species and produced viable offspring. From evolutionary and ecological perspectives, inhabiting brackish mangrove forests entails very specific adaptations of diet, behavior, and resource utilization. It is one of only two known species of lizard, the other being a species of Anole
Norops
Norops is the proposed generic name for 150 lizard species traditionally classified in the genus Anolis . Guyer and Savage applied this name to a group that Etheridge designated the "beta anoles" on the basis of skeletal characters that distinguished them from all other anole species...
, Norops utilensis, that lives solely in mangrove forests.
Description
The Utila iguana has a grey-brown to black coloring when young, the only species of spiny-tail iguana with such a dark color when young. Other members of the genus have a green or yellow coloring when young and turn darker with age. As this animal matures it can be a blue or light gray in color, depending on heat conditions or even the animal's temper.Males achieve a maximum length of 76 centimetres (29.9 in), while females are typically 30% smaller at 56 centimetres (22 in). Males have a small dewlap and a dorsal crest made up of 56 large dorsal spines, making the animal 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:...
. This dorsal crest consists of white and black spines arranged in alternating groups of two or three of the same color.
Diet
Like most iguanids, Ctenosaura bakeri is primarily herbivorous, eating flowerFlower
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, leaves, stems, and fruit
Fruit
In broad terms, a fruit is a structure of a plant that contains its seeds.The term has different meanings dependent on context. In non-technical usage, such as food preparation, fruit normally means the fleshy seed-associated structures of certain plants that are sweet and edible in the raw state,...
, but they will opportunistically eat smaller animals, eggs, and arthropod
Arthropod
An arthropod is an invertebrate animal having an exoskeleton , a segmented body, and jointed appendages. Arthropods are members of the phylum Arthropoda , and include the insects, arachnids, crustaceans, and others...
s that inhabit the mangroves. It has been observed eating smaller green iguana
Green Iguana
The Green Iguana or Common Iguana is a large, arboreal herbivorous species of lizard of the genus Iguana native to Central and South America...
s (Iguana iguana) and geckos such as Hemidactylus frenatus.
Reproduction
Adults make their homes within holes in various mangrove trees and maintain an arboreal existence whereas the young are strictly terrestrialTerrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...
for the first year of their lives. As the Utila iguana cannot successfully lay its eggs in the mangrove swamps, the gravid females are forced to migrate to nearby sandy beaches in order to bury their clutches of eggs so they can incubate in the hot sun. After digging their nest burrows and laying their eggs, the females abandon the nests and return to the mangroves. Sixty to seventy-four days later the hatchlings emerge and move back to the swamps.
The hatchlings are 15 centimetres (5.9 in) long, the body length being a mere 3 centimetres (1.2 in) with the tail accounting for 12 centimetres (4.7 in) of its total length. The hatchlings' dark skin color enables them to blend in with the dark floor of the mangrove forests to help elude predators.
Conservation status
Gunther Köhler found the species at the brink of extinction, perhaps even functionally extinct in the wild as of 1994 due to overhunting and its restricted habitat. As a result, the Iguana Research and Breeding Station was built in April 1997 with the help and funds of various organizations such as the Frankfurt Zoological SocietyFrankfurt Zoological Society
The Frankfurt Zoological Society is an independent, non-profit conservation organisation based in Frankfurt am Main, Germany. The society is funded through membership fees, donations, bequests, grants and earnings from its endowment fund.-History:...
, the Senckenberg Nature Research Society
Senckenberg Museum
The Naturmuseum Senckenberg in Frankfurt is the second largest museum of natural history in Germany. It is particularly popular with children, who enjoy the extensive collection of dinosaur skeletons: Senckenberg boasts the largest exhibition of large dinosaurs in Europe. One particular treasure is...
, AFE-COHDEFOR (State Forestry Administration-Honduran Forestry Development Corporation), BICA (Bay Islands Conservation Association)
BICA Honduras
The Bay Islands Conservation Association is a non-profit, non-governmental organization founded in 1991 by the people living in the Bay Islands in order to initiate and coordinate efforts in protecting the Islands’ fragile natural resources. BICA’s operation and projects are funded through the...
and the National Autonomous University of Honduras
National Autonomous University of Honduras
The National Autonomous University of Honduras is the national public university of Honduras. It was founded in 1847 and has many campuses throughout the country.-Autonomy:...
.
This species currently has an estimated wild population of 10,000 animals in 2-3 subpopulations, but is greatly threatened by loss of habitat, as mangrove forests are being used as garbage dump sites and deforested for the construction of homes, resorts, and marina
Marina
A marina is a dock or basin with moorings and supplies for yachts and small boats.A marina differs from a port in that a marina does not handle large passenger ships or cargo from freighters....
s. Beach habitat is being lost as natural vegetation is removed in preparation for hotel and road construction. According to a survey conducted by the IUCN, exotic invasive plants cover the ground near the mangroves and make the area inappropriate for nesting sites. The iguana is locally hunted for meat, although efforts to educate locals have helped reduce this somewhat in recent years.
In 2004, as a result of Köhler's expedition and subsequent book, Reptiles of Central America, the Conservation Project of the Utila Iguana (CPUI) was founded. The International Iguana Society and the CPUI have sought to purchase land to preserve habitats for the iguanas and plan to establish an outpost manned by Iguana Research and Breeding station personnel, who will aid in monitoring the property and work with developers to select building sites that preserve as much undisturbed beach area as possible.
The Iguana Research and Breeding station employs a "head-starting" program for newly hatched iguanas. "Head-starting", originally used to protect hatchling sea turtles, is a process by which iguana eggs are hatched in an incubator and the animals are protected and fed for the first 20 months of their lives. In the case of the Utila iguana, 50% of the animals hatched at the Center are maintained for the head-start program and the rest are released into mangrove forests after hatching. The purpose is to get the animals to a size where they are more capable of fleeing from or fighting off predators. The program has proven successful, as the iguanas behave like their wild-born counterparts. The success of the Utila program serves as a blueprint for other such programs in the Caribbean, particularly with 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...
species such as the Cuban Iguana and Blue Iguana
Blue Iguana
The Blue Iguana or Grand Cayman Iguana is a critically endangered species of lizard of the genus Cyclura endemic to the island of Grand Cayman. Previously listed as a subspecies of the Cuban Iguana, it was reclassified as a separate species in 2004 because of genetic differences discovered four...
.
Zoological institutions
The Utila iguana is maintained in a number of zoos throughout Europe, as well as two in the United States (Fresno Chaffee Zoo and the Fort Worth ZooFort Worth Zoo
The Fort Worth Zoo is a zoo in Fort Worth, Texas, USA. Founded in 1909 with one lion, two bear cubs, an alligator, a coyote, a peacock and a few rabbits, the Zoo now is home to 5000 native and exotic animals; has been named as a top zoo in the nation by Family Life magazine, the Los Angeles Times...
), each institution serving as an ex-situ
Ex-situ conservation
Ex-situ conservation means literally, "off-site conservation". It is the process of protecting an endangered species of plant or animal outside of its natural habitat; for example, by removing part of the population from a threatened habitat and placing it in a new location, which may be a wild...
breeding center. In September, 2007, the London Zoo
London Zoo
London Zoo is the world's oldest scientific zoo. It was opened in London on 27 April 1828, and was originally intended to be used as a collection for scientific study. It was eventually opened to the public in 1847...
successfully managed to breed Ctenosaura bakeri for the first time outside of Utila, an important step to ensure their survival if the species is lost from its natural habitat by hurricanes or over-hunting. The population is currently stable, but future declines are expected as a result of the threats mentioned above.
According to the International Species Information System
International Species Information System
-External links:*...
, the following zoological parks maintain Ctenosaura bakeri in their exhibits.
| Institution | Male(s) | Female(s) | Unknown | Born in the last year |
|---|---|---|---|---|
| Barcelona Zoo Barcelona Zoo Barcelona Zoo is a zoo in the Parc de la Ciutadella in Barcelona, Catalonia, Spain... |
0 | 0 | 2 | 0 |
| Blackpool Zoo Blackpool Zoo Located two miles from Blackpool's sea-front in Lancashire, England, Blackpool Zoo provides a home to over 1,500 animals from all over the world. The Zoo aims to provide its visitors with a stimulating, informative and enjoyable experience that demonstrates its role in the conservation of... |
1 | 1 | 0 | 0 |
| Cotswold Wildlife Park Cotswold Wildlife Park The Cotswold Wildlife Park and Gardens exhibits mammals, birds, reptiles, amphibians and invertebrates from all around the world. The Park is set in of landscaped parkland and gardens in Oxfordshire, England. Around 350,000 people visited the park in 2005.... |
0 | 0 | 1 | 0 |
| Chester Zoo Chester Zoo Chester Zoo is a zoological garden at Upton-by-Chester, in Cheshire, England. It was opened in 1931 by George Mottershead and his family, who used as a basis some animals reported to have come from an earlier zoo in Shavington. It is one of the UK's largest zoos at... |
1 | 1 | 0 | 0 |
| Zoo d'Amnéville Zoo d'Amnéville -External links:*... |
1 | 0 | 0 | 0 |
| Jersey Zoo | 1 | 2 | 3 | 0 |
| London Zoo London Zoo London Zoo is the world's oldest scientific zoo. It was opened in London on 27 April 1828, and was originally intended to be used as a collection for scientific study. It was eventually opened to the public in 1847... |
1 | 1 | 3 | 3 |
| Plock Plock Płock is a city in central Poland, on the Vistula river. According to the data provided by GUS on 30 June 2009 there were 126,675 inhabitants. It is located in the Masovian Voivodeship , having previously been the capital of the Płock Voivodeship . It now is a capital of a Powiat at the extreme... Zoo |
1 | 0 | 2 | 0 |
| Rotterdam Zoo | 2 | 3 | 0 | 0 |
| Museum of Natural History of Tournai Tournai Tournai is a Walloon city and municipality of Belgium located 85 kilometres southwest of Brussels, on the river Scheldt, in the province of Hainaut.... |
1 | 0 | 0 | 0 |
| Whipsnade Zoo | 1 | 2 | 13 | 13 |
| European Subtotal | 10 | 10 | 26 | 13 |
| Fort Worth Zoo Fort Worth Zoo The Fort Worth Zoo is a zoo in Fort Worth, Texas, USA. Founded in 1909 with one lion, two bear cubs, an alligator, a coyote, a peacock and a few rabbits, the Zoo now is home to 5000 native and exotic animals; has been named as a top zoo in the nation by Family Life magazine, the Los Angeles Times... |
4 | 1 | 2 | 0 |
| Fresno Chaffee Zoo | 0 | 1 | 2 | 0 |
| US Subtotal | 4 | 2 | 4 | 0 |
| Totals | 14 | 12 | 30 | 13 |