Bahamas rock iguana (Cyclura carinata)

Description

What’s the World’s Favourite Species?

Bahamas rock iguana fact file

• Description
• Biology
• Range
• Habitat
• Status
• Threats
• Conservation
• Find out more
• Glossary
• References
• Print factsheet

Bahamas rock iguana description

Bahamas rock iguanas are part of a group of large, ‘dinosaur-like’ lizards known as the West Indian rock iguanas (Cyclora spp.), which are widely recognised as amongst the most endangered lizards on earth ^{(4) (5)}. This impressive looking species is adorned with a crest of 80 to 110 scales down the centre of its back, and rings of enlarged spiny scales around its tail ⁽⁵⁾. Body size and colour vary among island populations, with individuals ranging from grey to brown to dull green. Nine to ten vertical stripes mark the iguana’s back and sides, but fade with age. Some populations bare a vermiculated pattern on the head and neck, and have pale blue dorsal crest scales and a reddish-brown tail in adult males. The Bartsch’s iguana subspecies is characterised by having a yellow dorsal crest, a golden iris, and adults have a network of faint yellow-brown lines on the body ⁽⁵⁾.

Also known as

Bartsch’s iguana, Turks and Caicos ground iguana, Turks and Caicos iguana.

French

Cyclure des Îles Turks et Caïques, Iguane terrestre des Îles Turks et Caïques.

Size

Male snout-to-vent length: up to360 mm ⁽²⁾

Female snout-to-vent length: up to290 mm ⁽²⁾

Male weight: up to1.86 kg ⁽²⁾

Female weight: up to1.14 kg ⁽²⁾

Bahamas rock iguana biology

The Bahamas rock iguana searches for food both on the ground and in trees. The diet is primarily herbivorous, consisting of fruit, flowers and leaves of at least 58 species, but occasionally also includes insects, molluscs, crustaceans, arachnids, lizards and carrion ⁽¹⁾.

Adult males are territorial all year round, seemingly to guard access to the food and females in their range. Mating is seasonal, taking place in May, and females produce a single clutch of two to nine eggs a year, which are laid in the nest burrow in June. Although females show no territorial behaviour during the rest of the year, they will actively defend the burrow for several days to several weeks after nesting, in order to protect their eggs from potential danger ⁽¹⁾. The eggs hatch in September, after an incubation period of about 90 days ⁽⁵⁾. Sexual maturity is not attained until seven years of age for males, six to seven years for females, and evidence suggests that certain individuals live to at least 20 years old ⁽¹⁾.

Bahamas rock iguana range

The nominate subspecies, the Turks and Caicos ground iguana (C. c. carinata), is found on 50 to 60 of the islands of the Turks and Caicos island banks, located southeast of the Bahamas, which are politically separate from the Bahamas but geologically part of the Bahama Archipelago ^{(1) (5)}. The most important remaining populations are on three large cays; Big Ambergris, Little Ambergris and East Bay ^{(1) (5)}. The Bartsch’s iguana subspecies (C. c. bartschi) is found only on Booby Cay at the eastern end of Mayaguana Island in the southern Bahamas ⁽¹⁾.

Bahamas rock iguana habitat

Most abundant in rocky coppice and sandy strand vegetation habitats, with sandy habitat required for nesting. This diurnal species retreats at night into burrows it has dug or into natural crevices in or under rocks ⁽⁵⁾.

Bahamas rock iguana status

Classified as Critically Endangered (CR B1ab(i,ii,iii,iv,v)) on the IUCN Red List 2004 ⁽¹⁾ and listed on Appendix I of CITES ⁽³⁾. Subspecies: Bartsch’s iguana or Booby Cay ground iguana (C. c. bartschi) is classified as Critically Endangered (CR B1+2ce, C2b) and the Turks and Caicos ground iguana (C. c. carinata) is classified as Critically Endangered (CR B1+2abcde) on the IUCN Red List 2004 ⁽¹⁾.

Bahamas rock iguana threats

At least 13 iguana subpopulations, most on relatively large islands, have disappeared over the last 20 years, predominantly due to ongoing habitat loss and the spread of introduced or feral mammal predators, with this decline apparently accelerating ⁽¹⁾. The primary threat in the Turks and Caicos Islands is introduced mammals such as cats, dogs and rats, which managed to almost completely destroy one population of 5,000 iguanas on Pine Cay in just three years ⁽⁵⁾. Worryingly, feral cats have recently crossed a newly formed sand spit from Pine and Water Cay to Little Water Cay, an important nature reserve that was previously cat-free. Feral livestock such as goats, cows, donkeys and horses also pose a significant threat, through competing for food, altering vegetation compositions of the islands, and trampling soft substrates where these iguanas borrow and nest. Development for tourism is an increasing cause of habitat loss and an additional cause for concern. The population of the Bartsch’s iguana subspecies on Booby Cay has been protected to a degree by the fact that the cay is not readily accessible from the settlements on Mayaguana, minimising disturbance. The main immediate threat to this population on Booby Cay is the presence of goats, which are over-browsing vegetation and causing extensive habitat degradation. Environmental catastrophes here, such as hurricanes or storm surges, also pose a very real danger ⁽¹⁾.

While there are no reports of poaching on Booby Cay, iguanas on the Turks and Caicos Islands are occasionally eaten by local fishermen and illegal international trade is thought likely to occur, despite being undocumented ⁽¹⁾.

Bahamas rock iguana conservation

Many of the Turks and Caicos Islands are protected by being encompassed in national parks, nature reserves and sanctuaries, a number of which support Bahamas rock iguana populations. Unfortunately, many of these reserves still suffer from the effects of introduced mammals and few government resources have been allocated to maintain or enforce protection of non-marine parks ⁽¹⁾. However, the establishment of the National Trust for the Turks and Caicos Islands in 1994 has significantly increased the conservation of terrestrial wildlife. The National Trust has been granted stewardship of Little Water Cay, and similar transfers of Little Ambergris and East Bay Cays are currently pending. On Little Water Cay, boardwalks and observation towers have been constructed at two popular landing sites to reduce the damaging impacts of tourism, and a visitation fee has been implemented with the proceeds going towards supporting conservation activities. A trapping programme to remove feral cats from Pine, Water, and (if necessary) Little Water Cays has also been established by the National Trust ⁽⁵⁾.

Legislation to protect iguanas within these islands has recently been drafted, and in November 2003 a Conservation and Management Plan was drawn up, which lays out a comprehensive strategy to conserve and restore populations of the Turks and Caicos iguana within its historic range, and perpetuate it as a symbol of national pride ⁽¹⁾. Beginning in 2000, the translocation of 218 animals was undertaken, from islands where they are currently threatened to four uninhabited cays within the Turks and Caicos reserve system. To date, the translocated iguanas have experienced a 98 percent survival rate ⁽⁶⁾. This example provides hope for similar translocations in the future to other islands where the species has dwindled or been extirpated ^{(7) (8)}.

On Booby Cay, the Bartsch’s iguana subspecies is protected like all Bahamian rock iguanas under the Wild Animal Protection Act of 1968. Additionally, the Bahamas National Trust has proposed to the government that Booby Cay, which is also of great importance to nesting seabirds, be named a protected area under the national parks system. Most importantly, the removal of feral goats has been planned, which would effectively eliminate the main threat to this subspecies and massively help its chances of survival ⁽⁵⁾.

View information on this species at the UNEP World Conservation Monitoring Centre.

Find out more

For more information on the Bahamas rock iguana see:

IUCN Red List:
http://www.redlist.org

Alberts, A. (1999) West Indian Iguanas: Status Survey and Conservation Action Plan. IUCN/SSC West Indian Iguana Specialist Group, Gland, Switzerland and Cambridge. Available at:
http://www.iucn-isg.org/actionplan/

Authentication

Glossary

Diurnal

Active during the day.

Dorsal

Relating to the back or top side of an animal.

Extirpated

Eradicated; destroyed totally.

Herbivorous

Diet comprises only vegetable matter.

Vermiculations

A pattern of fine, wavy, worm-like lines or streaks of colour.

References

1. IUCN Red List (January, 2006)
   http://www.redlist.org
2. Cyclura.com (March, 2006)
   http://www.cyclura.com/index.php?module=ContentExpress&func=display&ceid=27&meid
3. CITES (January, 2006)
   http://www.cites.org
4. Hudson, R. (1996) AZA Species Survival Plan Profile – West Indian Rock Iguanas. Endangered Species UPDATE, 13. Available at:
   http://www.umich.edu/~esupdate/library/96.07-08/contents.html
5. Alberts, A. (1999) West Indian Iguanas: Status Survey and Conservation Action Plan. IUCN/SSC West Indian Iguana Specialist Group, Gland, Switzerland and Cambridge. Available at:
   http://www.iucn-isg.org/actionplan/
6. Conservation and Research for Endangered Species (CRES) (March, 2006)
   http://cres.sandiegozoo.org/projects/sp_turks_caicos_iguanas.html
7. West Indian Iguana Specialist Group. (2000) Taxon Reports - C. c. carinata. West Indian Iguana Specialist Group Newsletter, 3(1): 7 - 14. Available at:
   http://www.iucn-isg.org/newsletters/pdf/WIISG_News_3(1).pdf
8. Mitchell, N., Haeffner, R., Veer, V., Fulford-Gardner, M., Clerveaux, W., Veitch, C.R. and Mitchell, G. (2002) Cat eradication and the restoration of endangered iguanas (Cyclura carinata) on Long Cay, Caicos Bank, Turks and Caicos Islands, British West Indies. In: Veitch, C.R. and Clout, M.N. (Eds) Turning the tide: the eradication of invasive species. IUCN SSC Invasive Species Specialist Group, IUCN, Gland, Switzerland and Cambridge, UK. Available at:
   http://issg.appfa.auckland.ac.nz/database/species/reference_files/TURTID/Mitchell.pdf