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 iguanas 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 in length, while females are smaller, with a length of up to . 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.
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 possibly a landbridge to the mainland lost during the close of the last ice age.
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 , while females are typically 30% smaller at . 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.
The hatchlings are long, the body length being a mere with the tail accounting for 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.
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 marinas. 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.
According to the International Species Information System, the following zoological parks maintain Ctenosaura bakeri in their exhibits.
|Institution||Male(s)||Female(s)||Unknown||Born in the last year|
|Cotswold Wildlife Park||0||0||1||0|
|Museum of Natural History of Tournai||1||0||0||0|
|Fort Worth Zoo||4||1||2||0|
|Chaffee Zoological Gardens||0||1||2||0|