Overview

Brief Summary

Biology

Rhinoceros iguanas are active during the day and, like many reptiles, regulate their body temperature by basking in the sunshine to warm up and seeking shade when too hot (2) (4). At night they retreat to caves, hollow tree trunks, burrows and rock crevices. These sheltered rest areas are so important that males will actively defend territories containing retreats attractive to females (2). Breeding occurs once a year, either just before or at the start of the first rainy season (2), around April to May (4) (6). Approximately 40 days after mating, usually between June and August (4) (6), females lay a clutch of two to 34 eggs (average of 17) into a nest cavity dug in the sand (2). Females may guard the nest for a number of days after laying, and the young hatch after 85 days (2). The young rhinoceros iguanas are independent from hatching, with no parental investment as they grow (4). Although longevity records are not available for the rhinoceros iguana, large rock iguanas are amongst the longest lived lizards in the world, and most species live for several decades and can take years to reach maturity (2). This iguana is primarily herbivorous, feeding on a variety of leaves, fruits, flowers, and seeds (2) (4). However, insects, land crabs and carrion (especially dead birds and fish) will occasionally be taken (4), and caterpillars are known to be part of the diet on Mona Island (2). Young iguanas in particular are thought to feed on insects and other small animals (4).
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Description

The common name of this massive, heavily built iguana is inspired by the several enlarged, horn-like scales on its snout, resembling the horns of a rhinoceros (4) (5). These are more prominent in males (4) (5), and are accompanied in both sexes by two distinctive, round pads of fatty tissue crowning the head (2) (6). Rough scales cover the body, which is uniformly greyish-brown, olive-green (4) (5), or even black in colour, lacking the bright colours that adorn several other iguana species (2). This sombre colouration helps camouflage the animal against the rocks and scrub of its habitat (6).
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Distribution

Range Description

The Mona Island iguana is endemic to the remote island of Mona, a low-profile limestone plateau situated midway between Puerto Rico and Hispaniola. The 11 by 7 km island lies within a deep sea channel known as the Mona Passage, and present submarine banks offer no evidence of former connections with either Puerto Rico or Hispaniola. The entire island is occupied by iguanas.
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Range Description

Rhinoceros iguanas are still widely distributed throughout Hispaniola, including most of its offshore islands. Their current geographic range is fragmented relative to their more continuous historical distribution, and is strongly associated with xeric regions of lower human population density. Most iguana concentrations are found along the southern side of Hispaniola, with the highest numbers in south-southwestern Dominican Republic.

In the Dominican Republic a minimum of ten subpopulations are known. In Haiti ten or fewer increasingly threatened subpopulations may still exist.
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Geographic Range

Cyclura cornuta is found only on the island of Hispaniola in the Caribbean Sea (Hamlett 2002). A closely related species or subspecies (scientific opinions vary) was found on Navassa Island, but is now believed extinct. There is a living subspecies on Mona Island, near Puerto Rico.

Biogeographic Regions: neotropical (Native )

Other Geographic Terms: island endemic

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Continent: Caribbean North-America
Distribution: Hispaniola (Dominican Republic, Haiti), Isla Beata, Ile de la Petite Gonave,  Ile de la Tortue, Ile Grande Cayemite, Ile de la Petite Cayemite, Isla Saona,  Isla Cabritos, Navassa, Isla Mona, Puerto Rico (USA, Florida)  Cyclura cornuta cornuta: Hispaniola and satellites.
Type locality: 'Sainte-Domingue ... dans les mornes de l'hôpital, entre l'Artibonite & les Gonaïves.  Cyclura cornuta onchiopsis (SYNTYPES USNM 9977, USNM 12239, MCZ 4717): Navassa Island.  Cyclura cornuta stejnegeri (HOLOTYPE USNM 29367): Isla Mona.
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Range

The nominate subspecies, C. c. cornuta, is found in the West Indies on Hispaniola (Haiti and the Dominican Republic) and surrounding islands. As its common name implies, the Mona Island iguana (C. c. stejnegeri) subspecies is endemic to the remote island of Mona, a small 11 by 7 km island situated midway between Puerto Rico and Hispaniola (2). Another closely related species or subspecies (scientific opinions vary) was found on Navassa Island, but is now believed extinct (4).
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Physical Description

Morphology

Physical Description

The skin of C. cornuta has rough epidermal scales and is grayish brown or olive in color. The species is definitively identied by the large size of certain scales on the head, but few other iguana species are as large or have the "horns" (actually enlarged scales) on their heads. These horns are the source for the name for of the species. Males are larger than females and have relatively larger horns as well (Hamlett 2002, Cyclura.com 2002).

Range mass: 28.6 to 48.4 kg.

Range length: 60.96 to 121.92 cm.

Average length: 91.30 cm.

Other Physical Features: ectothermic ; bilateral symmetry

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Ecology

Habitat

Habitat and Ecology

Habitat and Ecology
Mona’s climate is dry subtropical (800 mm rainfall per year), supporting an open canopy forest of short, seasonally deciduous trees, shrubs, cacti, and bromeliads. Rainwater percolates rapidly through the porous limestone substrate, allowing no freshwater streams or ponds. Solution channels and sinkholes that penetrate the island’s rock topography offer underground shelters that are utilized by both male and female iguanas, and retreats attractive to females are vigorously defended by males. Some males hold territories year-round, while others defend them only during the brief June mating season.

Because more than 95% of Mona’s surface is rock, females must migrate to scarce soil deposits for nesting. The onset of the two-week, mid-summer nesting season appears to be cued by photoperiod and females are especially wary at this time. Most egg laying (74%) occurs in sandy clearings on the island’s southern coastal terraces, with the remaining 26% in sinkhole depressions (Haneke 1995). Mean clutch size is 12 eggs. Surviving eggs hatch approximately 83 days after laying, during the latter half of October. Newly emerged young are large and only the smallest juveniles are susceptible to indigenous predators. Coloration and behavior of hatchlings suggests that aerial predators have long been a threat to this age class (Wiewandt 1977).

Females require 6 to 7 years to reach sexual maturity. Although longevity records are not available, Mona iguanas, like all large rock iguanas, are probably among the longest lived lizards in the world. Consequently, populations are slow to recover from losses over time.

Mona iguanas are primarily herbivorous, with a strong preference for fruits that fall from native trees. Some animal matter is eagerly taken, especially caterpillars when available. Trees reach their greatest size and diversity in scattered sinkhole depressions, areas that are of particular importance to the welfare of the iguana population.

Systems
  • Terrestrial
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Habitat and Ecology

Habitat and Ecology
Rhinoceros iguanas are most abundant in, although not restricted to, dry forests characterized by xeric, rocky habitats of eroded limestone in coastal terraces and lowlands of the mainland and several offshore islands and small cays. In areas supporting iguanas, mean annual rainfall ranges from 470 to 1,000 mm, and mean annual temperature is 25°C. With some exceptions, the species ranges in elevation from -35 m (Isla Cabritos, Lake Enriquillo) up to 400 m. They are found in a variety of subtropical life zones and habitat types, including thorn scrub woodland, dry forest and transitional semideciduous to subtropical moist forests.

Like other rock iguanas, rhinoceros iguanas are diurnal, spending the night in retreats. Rock crevices, caves, burrows dug in soil or sand, and hollow trunks are also used during the day for resting, cooling or sheltering. Males defend territories containing retreats attractive to females. High trees and exposed rocks are used by males for basking and overseeing defended areas. Mating takes place at the beginning of or just prior to the first rainy season of the year. Females lay from 2 to 34 eggs, with an average clutch size of 17. Females guard nests for several days after laying, and incubation lasts approximately 85 days. Females probably become sexually mature at 2-3 years of age. Rhinoceros iguanas feed on fruits, leaves and flowers of a variety of plants, depending on availability. Additional information on their ecology and natural history is summarized by Schwartz and Henderson (1991).

Systems
  • Terrestrial
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The natural habitat of C. cornuta is typically described as dry forest, scrub, or desert. This biome receives very little rain annually and the plants and animals which occupy it reflect the sun-drenched, arid environment. Mostly small trees and shrubs, cacti, and mesquite may surround the burrows that C. cornuta inhabits. Iguanas exhibit a considerable amount of plasticity in their habitat selection and C. cornuta is no exception. This species is primarily found near coastlines, however, human expansion has forced many populations to retreat further inland. This species requires warm temperatures and lots of solar radiation. Cyclura cornuta is typically found in regions where the annual mean temperature is at least 27 degrees Celsius. It has been displaced from much of its original range on Hispaniola by habitat destruction and introduced predators (Hamlett 2002, Cyclura.com 2002)

Range elevation: l (low) m.

Habitat Regions: tropical

Terrestrial Biomes: desert or dune ; forest ; scrub forest

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Rhinoceros iguanas are terrestrial reptiles that prefer dry, rocky terrain in coastal areas, but also inhabit scrub woodlands, semi-deciduous forests and dry to subtropical, moist forests (2) (6). Although primarily coastal, human expansion has forced many populations to retreat further inland (4). Subtropical Mona Island is vegetated with an open canopy forest of short, seasonally deciduous trees, shrubs, cacti and bromeliads (2).
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Trophic Strategy

Food Habits

Members of C. cornuta have a variable diet both seasonally and ontogenetically. Rhinoceros iguanas are mainly herbivores, eating a wide variety of leaves, fruits, flowers, and seeds. They occasionally eat animal food, mainly insects, land crabs, or carrion (especially dead birds and fish). Young iguanas in particular may take insects and other small animals. Iguanas that locate a food source (e.g. a fruiting bush) will actively defend it from conspecifics (Animal Network).

Animal Foods: carrion ; insects; terrestrial non-insect arthropods

Plant Foods: leaves; seeds, grains, and nuts; fruit; flowers

Primary Diet: herbivore (Folivore , Frugivore , Granivore )

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Associations

Ecosystem Roles

Cyclura cornuta has been documented to feed on fruits. Because most seeds are difficult to digest without special bacteria, they often remain intact and end up in the animal's feces. This helps to both spread the seed and to fertilize it. C. cornuta therefore is crucial in communities in which it is the dominant frugivore.

Ecosystem Impact: disperses seeds

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Predation

The skin color of C. cornuta allows it to blend in with its environment. This species also exhibits behaviors which are thought to deter predators as well as competitors. As discussed above, these include elaborate head and neck movements intended to make the lizard look larger and more fierce. These defenses don't work very well against introduced predators.

Known Predators:

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Known predators

Cyclura cornuta is prey of:
Herpestidae
Homo sapiens
Sus scrofa
Canis lupus familiaris

This list may not be complete but is based on published studies.
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Known prey organisms

Cyclura cornuta preys on:
Arthropoda
Insecta

This list may not be complete but is based on published studies.
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Life History and Behavior

Life Cycle

Development

These iguanas hatch from eggs and are independent after hatching. They mature at 5 to 9 years of age (Cyclura.com 2002).

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Life Expectancy

Lifespan/Longevity

Very little has been published regarding the longevity of this species because it is difficult to monitor in the wild. A life of 20 years in captivity is reported (Hamlett 2002), and some researchers predict that these animals may live decades long than that in the wild (Kaplan 2002, citing Blair).

Range lifespan

Status: captivity:
20 (high) years.

Average lifespan

Sex: male

Status: captivity:
16.7 years.

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Lifespan, longevity, and ageing

Maximum longevity: 22.9 years (captivity)
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Reproduction

Evidence for a polygynous mating system with social rank determining matings has been published. This corresponds to the fact that C. cornuta appears to be extremely territorial and males especially will attempt to dominate and intimidate conspecifics with head movements and body gyrations. They use similar motions to attract females, and may also use these head bobs and nods to scare away predators (Hunsaker II, et al. 1969).

Mating System: polygynous

The beginning of the mating season is late May, and C. cornuta is oviparous, so eggs are laid about 40 days after mating, usually in early August. Females dig burrows up to a meter and a half long in which to incubate the eggs and must keep them at a minimum of 30 degrees Celsius. Clutch size is extremely variable and may range from 5 to 20 eggs. Resource competition and/ or abundance of predators is thought to account for variations in egg-laying behavior(Hunsaker II, et al. 1969).

Breeding season: late May to early June

Range number of offspring: 5 to 20.

Average number of offspring: 10.

Range gestation period: 4 to 5 months.

Range age at sexual or reproductive maturity (female): 5 to 9 years.

Range age at sexual or reproductive maturity (male): 5 to 9 years.

Key Reproductive Features: iteroparous ; seasonal breeding ; gonochoric/gonochoristic/dioecious (sexes separate); fertilization (Internal ); oviparous

There is no male parental care this species. Once females have laid their eggs, they sometimes guard the nest for a few weeks to prevent egg predation (D. Blair at Cyclura Research Information Collection).

Parental Investment: no parental involvement; female parental care

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Conservation

Conservation Status

IUCN Red List Assessment


Red List Category
EN
Endangered

Red List Criteria
A2ce

Version
2.3

Year Assessed
2000
  • Needs updating

Assessor/s
Garcia, M., Perez, N. & Wiewandt, T.

Reviewer/s

Contributor/s

Justification
Recent fieldwork indicates a current population of 1,500-2,000 adults with no evidence suggesting a 50% reduction in population size over the last 10 years or 3 generations.

History
  • 1996
    Endangered
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IUCN Red List Assessment


Red List Category
VU
Vulnerable

Red List Criteria
A1acde

Version
2.3

Year Assessed
1996
  • Needs updating

Assessor/s
Ottenwalder, J.

Reviewer/s

Contributor/s
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C. cornuta is threatened by human encroachment on and destruction of its natural habitat. The demand for old growth trees by the logging industry, limestone mining, pollution, predation, and wild fires have depleted the habitat and often forced this and many other species to migrate and/or go extinct. Haiti, a country mired in poverty, in particular has experienced a dramatic reduction in population due to poachers killing for food (Hamlett 2002). This species is listed as Vulnerable by the International Union for the Conservation of Nature, and is listed in Appendix I of CITES. This means that international trade in this species is generally forbidden with out strict permits from both exporting and importing countries. The closely related species/subspecies, C. cornuta stegneri, the Mona Island Ground Lizard, is considered Threatened by the U.S. Fish and Wildlife Department and protected under the Endangered Species Act.

US Federal List: threatened

CITES: appendix i

IUCN Red List of Threatened Species: vulnerable

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Status

Classified as Vulnerable (VU) on the IUCN Red List 2006 (1), and listed on Appendix I of CITES (3). Subspecies: the rhinoceros iguana (C. c. cornuta) is classified as Vulnerable (VU), and the Mona Island iguana (C. c. stejnegeri) is classified as Endangered (EN) on the IUCN Red List 2006 (1).
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Population

Population
Census figures indicate that the Mona iguana population is abnormally small. A survey of the similarly-sized rhinoceros iguana on Petite Gonave Island in Haiti indicated densities 26 times greater than those found on Mona. Wiewandt found that immature iguanas were scarce on Mona, representing only 5-10% of the population (Weiwandt 1977), and Moreno sighted only two juveniles among 118 iguanas seen (Moreno 1995). This contrasts sharply with Garcia’s unpublished data for rhinoceros iguanas (C. cornuta cornuta) on Isla Beata in the Dominican Republic, where all age classes are abundant and juveniles comprise approximately one-third of the population (see Grupo Jaragua 1994). Low iguana densities and the scarcity of juveniles on Mona suggest a senescent and declining population.

Population Trend
Decreasing
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Population

Population
Rhinoceros iguanas were common and widespread until the early 1950s, but accurate information concerning current population estimates on Hispaniola is lacking. Unpublished data, based on opportunistic surveys, are available for a few localities but are inadequate for extrapolation to other areas facing different levels of disturbance, particularly in Haiti. Observations on population and habitat trends recorded since the 1970s provide a fair but rough approximation of 10,000 to less than 17,000. Iguana densities are low in the majority of the areas where they presently occur and appear to be declining. Local extirpations are known from both Dominican Republic and Haiti. Populations are seemingly stable only on Isla Beata and the extreme of the Barahona Peninsula inside Parque Nacional Jaragua.

Population Trend
Decreasing
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Threats

Major Threats
The most pressing conservation management challenge on Mona today is that of exotic species. Having evolved in the near absence of predators, insular iguanas lack the behavioral and demographic attributes to cope with introduced mammals. Feral pigs regularly plunder iguana nests.

Feral cats are also present on Mona, and constitute the most serious threat currently impacting young iguanas. The devastating impact of cats on a population of Turks and Caicos iguanas was clearly documented (Iverson 1978), and there is little doubt that the present scarcity of juveniles on Mona is due primarily to the combined effects of pigs consuming eggs and cats preying on young.

Habitat modification due to intense browsing pressure by feral goats (resulting in forest trees being unable to propagate successfully and a severe reduction in leaf litter) may also threaten the iguanas.

Although lacking permanent settlements, Mona is a haven for recreational activities, including camping, fishing, swimming, scuba diving, beach combing, exploring, and hunting. Most of these activities are concentrated along the island’s sandy coastal terraces and within sinkhole depressions, areas of critical importance for iguana nesting. Haneke (1995) observed that new camping facilities had been recently added in iguana nesting areas at Playa de Pajaros. Mona iguanas are wary and easily disturbed while nesting, and visitors can unintentionally disrupt the egg-laying process. People and feral animals walking through nest site clearings during incubation may cause nest chambers to capsize, denying oxygen to developing eggs. These and other conflicts between iguanas and visitors are bound to intensify as recreational use of the island continues to expand. Goats regularly gather in sinkhole depressions on Mona’s plateau, and this may partially explain Heneke’s (1995) observation of complete nest failure there. Mona may have already exceeded its carrying capacity for low impact tourist visitation. Better supervision over visitors, particularly by strengthening educational programs, will become increasingly important as the number of people coming to Mona continues to grow.

Another recent concern for conservation of Mona iguanas is the emergence of an undefined disease or parasite that causes blindness. Recently, Haneke (1995) observed 15 blind adults on Mona, all with opaque, bluish eyes and apparently severely undernourished. Ramos (1964; cited in Kuns et al. 1965) lists 16 species of eye flies (family Chloropidae) occurring on Mona, including Hippelates pusio, which has been incriminated in the spread of catarrhal conjunctivitis in the United States. Studies are urgently needed to identify the pathogens and vectors responsible for blindness in the Mona iguana population.
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Major Threats
Habitat destruction, due to extraction of hardwoods and fuelwood, charcoal production, agriculture, livestock grazing and limestone mining, represents the major threat to rhinoceros iguanas in both the Dominican Republic and Haiti. In the Dominican Republic about 13% of the human population occupy dry forest regions. These areas are also the most economically depressed and exploitation of forest habitats for charcoal and fuelwood represent important sources of income. About 75-80% of the total national demand for these products originates from dry forest habitats. In the Dominican Republic, roughly 35% of rhinoceros iguana habitat has been lost, and approximately 75% of what remains is disturbed. Both figures are much higher for Haiti.

Other important threats are predation by feral dogs, cats, mongoose and pigs on adults, juveniles and eggs, and illegal hunting of subadults and adults for food and local trade. The use of iguanas for food in Haiti is extreme in rural areas where iguanas are conspicuous enough that local people are familiar with them. International trade of wild animals from Hispaniola, a conservation problem until the mid 1980s, has been controlled in the Dominican Republic under CITES since 1987, but no such control exists in Haiti.
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The main threat facing this species is habitat loss as a result of logging for hardwoods, exploitation for charcoal production and fuel wood, livestock grazing, agriculture and mining of limestone. In the Dominican Republic around 35% of suitable habitat has been totally lost; of the remaining habitat, 75% is disturbed and the situation is much worse in Haiti (2). Other threats include predation by dogs, cats, pigs, and mongooses, and illegal hunting by humans for food is a very serious problem in parts of Haiti, a country mired in poverty (2) (4). International trade in wild rhinoceros iguanas has been controlled since 1987 in the Dominican Republic, but not in Haiti (2). Introduced exotic species pose the most serious threat to the subspecies on Mona Island, which has evolved in the near absence of predators and is therefore ill-equipped to cope with the dangers they now pose. In particular, the combined effect of pigs consuming eggs and cats preying on young has resulted in the present scarcity of juveniles on the island. Feral goats may also be having a damaging impact by gathering in sinkhole depressions on Mona's plateau where the iguana nests, and also through intense browsing pressure affecting the vegetation of the island. Although there are no permanent settlements on the island, Mona attracts many recreational pursuits, including camping, fishing, swimming, scuba diving, beach combing, exploring, and hunting. Most of these activities are concentrated along the island's sandy coastal terraces and within sinkhole depressions, areas of critical importance for iguana nesting. An additional recent concern is the emergence of an unidentified disease or parasite that causes blindness in the iguana, which in turn appears to affect the iguana's ability to feed (2).
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Management

Conservation Actions

Conservation Actions
The Mona iguana is listed as threatened by the U.S. Fish and Wildlife Service and the PR-DNRE. In 1984, the U.S. Fish and Wildlife Service approved a recovery plan for the Mona iguana prepared by C. Diaz, PR-DNRE (Diaz 1984).

During the last 25 years, the PR-DNRE has instituted some important changes. The hunting season on Mona has been moved to a time outside the iguana nesting and incubation seasons. Together with the local herpetological society, Sociedad Chelonia, the government has created several new nesting areas on the southwestern coastal terrace. A number of clearings in the Casuarina forest have been established that are fenced off from goats and pigs but allow iguanas to pass freely. Fencing of remote nest sites is currently being undertaken by the PR-DNRE, the U.S. Fish and Wildlife Service Caribbean Office, the U.S. Coast Guard, the Sociedad Chelonia, and the Toledo Zoo. Researchers at the PR-DRNE and the Toledo Zoo have additionally begun to assess the nature of the blindness syndrome seen in several adult iguanas. Currently, PR-DNRE is conducting a long-term study to quantify the impact of feral cats on Mona Island wildlife.
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Conservation Actions

Conservation Actions
In the Dominican Republic, most rhinoceros iguana populations are either fully or partially protected inside existing national parks and reserves. Protected areas supporting iguana populations include Montecristi National Park, Parque Nacional del Este including Isla Saona, Parque Nacional Jaragua including Isla Beata, Las Caobas Strict Natural Reserve, El Acetillar scenic area, Sierra Martín García National Park, and Lago Enriquillo National Park, including Isla Cabritos. However, the foothill regions in the latter two areas remain only partially protected. Management in most protected areas is not intensive, and in some cases is restricted to legislation.

Compliance with international trade regulations is effective, aside from occasional smuggling of animals across the border with Haiti. Rhinoceros iguanas are protected nationally by Dominican wildlife regulations. Enforcement has improved during the past few years, but clearing of the natural habitat for development is not being prevented, and illegal hunting and poaching for food and for the local pet market continues. No formal protected areas are known within the present distribution of iguanas in Haiti. The status of protective legislation is also uncertain, although the rhinoceros iguana was included on a list of protected wildlife by the Ministry of Agriculture during the 1980s. Enforcement of any potentially existing wildlife regulations seems unlikely at present.

Rhinoceros iguanas are the most common rock iguana in captivity. A successful breeding program existed at the Parque Zoológico Nacional of the Dominican Republic (ZooDom) from 1974 to 1994, with an average of 100 young hatching annually. These efforts included experimental reintroductions of captive-bred young to several protected areas in the southwest Dominican Republic. Although a captive colony of almost 300 iguanas representing all age classes was maintained at ZooDom as of December 1994 the program has been adversely affected by administrative changes since January 1995. It is hoped that these problems can soon be resolved and the program resumed.

As of November 1995 rhinoceros iguanas elsewhere in captivity included 393,236 individuals at about 20 zoological institutions, with an additional 533 animals of unassigned subspecies, reported by seven American Zoo and Aquarium Association institutions (Christie 1995). The actual number may be higher considering holdings at some European zoos and many private collections.
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© International Union for Conservation of Nature and Natural Resources

Source: IUCN

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Conservation

International trade in the rhinoceros iguana is controlled by its listing under Appendix I of the Convention on International Trade in Endangered Species (CITES). Most populations occur within protected areas in the Dominican Republic, and the species is protected under national wildlife laws. Although enforcement of these laws has improved in recent years, habitat destruction remains a problem and illegal hunting for food and for the pet trade continues. Sadly, the situation looks bleaker in Haiti, where there are no formal protected areas supporting this species and enforcement of any existing wildlife laws is unlikely. There are a large number of rhinoceros iguanas in captive breeding programmes around the world, and some have even included experimental reintroductions of captive-bred young to several protected areas in the southwest Dominican Republic. Nevertheless, the conservation of existing wild populations must remain a priority. Suggested future needs include the establishment of local educational awareness campaigns to try to reduce illegal hunting, the strengthening and enforcement of existing legislation protecting the species, and the development of a national recovery strategy. Research and monitoring programmes are also essential in order to devise and guide appropriate conservation efforts (2). Mona Island is part of the Commonwealth of Puerto Rico, and is designated as a natural reserve by the Division of Natural Reserves and Refuges within the Puerto Rico Department of Natural Resources and the Environment (PR-DNRE). In conjunction with other organisations, the PR-DNRE has implemented some significant conservation measures, such as moving the hunting season to a time outside of the iguana's nesting season, fencing off important habitat and remote nest sites from goats and pigs, and conducting research into the impact of feral cats and the blindness syndrome seen in several adult iguanas. Nevertheless, as the number of visitors to the island continues to grow, it is essential that they are better supervised, and that educational programmes raise awareness of the potentially damaging effects recreational activities can have to this endangered subspecies (2).
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© Wildscreen

Source: ARKive

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Relevance to Humans and Ecosystems

Benefits

Economic Importance for Humans: Negative

This species will bite or scratch and strike with its tail if provoked or attacked, but is otherwise harmless and in no way detrimental to humans.

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Source: Animal Diversity Web

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Economic Importance for Humans: Positive

Rhinoceros iguanas are sometimes kept as pets, and in the past have been used as food. Currently they are not of great economic importance.

Positive Impacts: pet trade ; food

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Source: Animal Diversity Web

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