The Jamaican Iguana (Jamaican Ground Iguana, Jamaican Rock Iguana), Cyclura collei, is believed to be one of the most endangered lizard species at present [1]. The Iguanas are large and heavy-bodied, often green to blueish in colour, with darker olive-green colouration on the shoulders [3, 4]. Three dark chevrons can be seen along the animal's back, and the crest scales found here are often lighter in colour than the body [3, 4].
Male Jamaican Iguanas grow to almost 17 inches in length, and females usually to almost 15 inches [3]. The species shows small amounts of sexual dimorphism, as the dorsal crests of the males grow higher.
The species is primarily herbivorous, consuming a diverse range (over 100 species) of leaves, flowers and fruits [3].
Male Jamaican Iguanas grow to almost 17 inches in length, and females usually to almost 15 inches [3]. The species shows small amounts of sexual dimorphism, as the dorsal crests of the males grow higher.
The species is primarily herbivorous, consuming a diverse range (over 100 species) of leaves, flowers and fruits [3].
The Jamaican Iguana, Cyclura collei, likely has a remaining population of less than 100 individuals. Picture from [2]. |
Number left in existence:
Surveys of previous ranges have revealed the Jamaican Iguana is extinct in all areas aside from the Hellshire Hills [3]. A preliminary study in 1990 revealed a population of under 100 individuals, but found minimal juvenile recruitment [1]. The population in the area does appear to be increasing due to reintroduction and predator control, however it is unknown how protected any individuals straying out of this area are.
Geographical Range in the wild:
The small remaining geographical range of the Jamaican Iguana - a <10km squared range in the Hellshire Hills. |
Why they are endangered:
- A main reason for their decline is high levels of predation by introduced species; the massive population decline in the 19th century is partially attributed to the introduction of the Indian Mongoose [1, 4], and these have been found to prey on young iguanas and eggs at present. Introduction of dogs for pig hunting, cats and feral pigs has also harmed populations [1].
- Habitat destruction; their small habitat is being increasingly degraded by human encroachment from the edges [1].
- Extensive logging for charcoal production by humans has destroyed much of their suitable habitat [1]. This tree-cutting is illegal.
What can we do to help?
The central core area of the Hellshire Hills is now under extensive predator control, and mature Iguanas are being reintroducted; together this means the population in this area is increasing. The Hellshire Hills area is also protected by law under the Forest Act of 1996, however this has received little enforcement [1]. A conservation group specific to the species also captures, rears and releases the Iguanas, giving them a 'kick-start' [4].
The Iguanas main need now is translocation to predator-free islands (which obviously requires a lot of resources in moving the animals, and in locating and maintaining the islands as refuges), and further prevention of deforestation in their current range and these new areas. Translocation is highly important, as threatening development projects have been proposed for the Hellshire Hill area, including large-scale limestone mining, human settlements and tourism [1].
The Iguanas main need now is translocation to predator-free islands (which obviously requires a lot of resources in moving the animals, and in locating and maintaining the islands as refuges), and further prevention of deforestation in their current range and these new areas. Translocation is highly important, as threatening development projects have been proposed for the Hellshire Hill area, including large-scale limestone mining, human settlements and tourism [1].
References:
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