Ctenosaura bakeri

Ctenosaura bakeri was first described by Norwegian-born American zoologist Leonhard Stejneger in 1901, while working for the Smithsonian Institution.[8] The generic name, Ctenosaura, is derived from two Greek words: ctenos (Κτενός), meaning "comb" (referring to the comblike spines on the lizard's back and tail), and saura (σαύρα), meaning "lizard".[7] Its specific name, bakeri, is the Latinized form of Stejneger's friend and colleague Frank Baker, who was a former director of the National Zoo in Washington, D.C..[6]

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.[3]

Utila Spiny-tailed Iguana, in the London Zoo.

Endemic to Utila, an island off the northern Honduras coast, Ctenosaura bakeri is an inhabitant of 8 square kilometres (3.1 sq mi) of mangrove forests.[2] 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.[4][9] 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, Anolis utilensis, that lives solely in mangrove forests.[3]

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.[3][7]

Males achieve a maximum total length (including tail) of 76 centimeters (30 in), while females are typically 30% smaller at 56 centimeters (22 in) total length. Males have a small dewlap and a dorsal crest made up of 56 large dorsal spines, making the animal sexually dimorphic.[7] This dorsal crest consists of white and black spines arranged in alternating groups of two or three of the same color.[3]

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.[6] 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 Society, 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.[10]

This species currently has an estimated wild population of 10,000 animals in 2–3 subpopulations, but is greatly threatened by loss of habitat,[6] as mangrove forests are being used as garbage dump sites and deforested for the construction of homes, resorts, and marinas.[11] 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.[2] The iguana is locally hunted for meat, although efforts to educate locals have helped reduce this somewhat in recent years.[7][11]

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.[6] 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.[10]

The Iguana Research and Breeding station employs a "head-starting" program for newly hatched iguanas. "Head-starting", originally used to protect hatching sea turtles, is a process by which iguana eggs are hatched in an incubator and the animals are protected and fed until they are large enough to be protected from predation upon them. 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.[12]

• Köhler, Gunther (2003). Reptiles of Central America. Offenbach, Germany: Herpeton. p. 368. ISBN 3-936180-02-4.

Wikispecies has information related to Ctenosaura bakeri.

• Iguana Research and Breeding Station
• Fort Worth Zoo Museum of Living Art – Species List: Utila Island iguana
• Hope hatches for critically endangered lizard on the brink of extinction
• Profile on West Coast Iguana