The rhinoceros iguana (Cyclura cornuta) is a threatened species of lizard in the family Iguanidae that is primarily found on the Caribbean island of Hispaniola, shared by the Republic of Haiti and the Dominican Republic. They vary in length from 60 to 136 centimetres (24 to 54 in) and skin colors range from a steely gray to a dark green and even brown. Their name derives from the bony-plated pseudo-horn or outgrowth which resembles the horn of a rhinoceros on the iguana's snout.
Male rhinoceros iguana, Pedernales Province, Dominican Republic, 2007
Vulnerable (IUCN 2.3)
C. c. onchiopsis, Navassa Island iguana
C. c. stejnegeri, Mona Island iguana
The rhinoceros iguana is a species of lizard belonging to the genus Cyclura. The generic name (Cyclura) is derived from the Ancient Greek cyclos (κύκλος) meaning "circular" and ourá (οὐρά) meaning "tail", after the thick-ringed tail characteristic of all Cyclura. The rhinoceros iguana's specific name, cornuta, is the feminine form of the Latin adjective cornutus, meaning "horned" and refers to the horned projections on the snouts of males of the species. The species was first identified by Pierre Joseph Bonnaterre in 1789.
In addition to the nominate race (Cyclura cornuta cornuta) found on Hispaniola, there are two other subspecies of Cyclura cornuta, the Mona ground iguana (Cyclura cornuta stejnegeri) and the Navassa Island iguana (Cyclura cornuta onchiopsis), although the latter subspecies is believed to be extinct in the wild.
Anatomy and morphology :
The rhinoceros iguana, like other members of the genus Cyclura, is a large-bodied, heavy-headed lizard with strong legs and a vertically flattened tail. A crest of pointed horned scales extends from the nape of their neck to the tip of their tail. Their color is a uniform gray to brown drab. Most adults weigh 4.56 kilograms (10.1 lb) to 9 kilograms (20 lb)
These iguanas are characterized by the growth of bony prominent tubercles on their snouts which resemble horns. Dr. Thomas Wiewandt, who spent an extended period on Mona Island studying Cyclura cornuta stejnegeri, suggested that the horns, along with lateral spines and prominent parietal bulges, function as protective armor against sharp rocks or as defensive tools to facilitate the escape of males from the grasp of one another. Males possess an adipose pad in the form of a helmet on the occipital region of the head, and a large dewlap. This species, like other species of Cyclura, is sexually dimorphic; males are larger than females, and have more prominent dorsal crests and "horns" in addition to large femoral pores on their thighs, which are used to release pheromones.
Distribution and habitat :
Ranging throughout Hispaniola, Haiti and the Dominican Republic; rhinoceros iguana populations are stable only on Isla Beata and the extreme of the Barahona Peninsula inside Parque Nacional Jaragua. There are moderately dense populations in the southeastern region of Haiti and its offshore islands including the saltwater lake of Etang Saumatre. Populations in Haiti are even more endangered due to the deforestation and human clearing practices. In general, the iguanas are found most abundantly in, although not restricted to, scrub woodland, 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 a variety of subtropical life zones and habitat types. An individual was photographed on May 4, 2008 on the Limbe Island in Northern Haiti. It had been caught by a group of fishermen from Bas-Limbe, Bord de Mer village. The rhinoceros iguanas caught on Limbe Island are eaten by the local population. This sighting represents a new area previously not thought to be in the range of Cyclura cornata.
The rhinoceros iguana is a diurnal species living primarily in rocky outcroppings with little vegetation for cover. Although quick to flee when attacked or threatened, they will aggressively attack by biting and repeatedly striking with their thick tail if cornered.
on Limbe Island, Haiti
C. cyclura lair, Jaragua National Park
C. cyclura, Jaragua National Park
The rhinoceros iguana, like most Cyclura species is primarily herbivorous, consuming leaves, flowers, berries, and fruits from different plant species. A study in 2000 by Dr Allison Alberts of the San Diego Zoo revealed that seeds passing through the digestive tracts of Cycluras germinate more rapidly than those that do not. These seeds in the fruits consumed by cycluras have an adaptive advantage by sprouting before the end of very short rainy seasons. The rhinoceros iguana is also an important means of distributing these seeds to new areas (particularly when females migrate to nesting sites) and, as the largest native herbivores of their island's ecosystem, they are essential for maintaining the balance between climate and vegetation. Rhinoceros iguanas do appear to be opportunistic carnivores as individual animals have been observed eating small lizards, snakes, and insects.
Claw of rhinoceros iguana at Bristol Zoo
Male rhinoceros iguanas, unlike other members of the genus Cyclura, reach sexual maturity at four to five years of age. Females become sexually mature at two to three years of age. Male rhinoceros iguanas are territorial and the most aggressive males will have the largest range of territory. Mating takes place at the beginning of, or just prior to, the first rainy season of the year (May to June) and lasts for two to three weeks.Females lay from 2 to 34 eggs, with an average clutch size of 17, within 40 days. Females guard their nests for several days after laying their eggs, and incubation lasts approximately 85 days. It has been noted that their eggs are among the largest lizard eggs produced in the world.
Endangered status :
Although rhinoceros iguanas are the most common species of Cyclura kept in captivity there remain approximately 10-16,000 of these animals in the wild. A successful breeding program existed at the Parque Zoológico Nacional of the Dominican Republic (ZooDom) from 1974 to 1994, with an average of 100 babies hatching annually. These efforts included reintroductions of captive-bred "head-started" young to several protected areas in the southwest Dominican Republic in order to reduce the odds of predation by snakes and feral animals such as mongoose or cats. The program has not continued since 1995, due to an administrative change at the zoo.
As of 2009, a reintroduction of rhinoceros iguanas on the Samana Peninsula is planned by the Iguanario de los Tocones.
Rhinoceros iguana at the Frankfurt Zoo
The rhinoceros iguana is well established in captivity, both in public and private collections. As of 2007, rhinoceros iguanas in captivity throughout the United States total 39 males, 32 females, and 36 undetermined individuals at 20 zoological institutions, with an additional 533 animals of unassigned subspecies, reported by seven American Zoological and Aquarium Association institutions. The actual number may be much higher considering animals kept at European and Asian zoos and the many kept as pets in private collections. As a result, the demand for wild-caught animals to supply zoos and the pet trade has been reduced.
Despite these numbers, making them the most numerous species of Cyclura, they are still considered a CITES (Convention on International Trade in Endangered Species) protected animal.
Rhinoceros iguanas at the Schönbrunn Zoo in Vienna.
For the external links , refrences click here to read the full wikipedia article
Rhino iguana (Buddy) and Logan eating breakfast
Other Websites :
Care articles :
1- Rhinoceros Iguana
courtesy to : www.reptilesmagazine.com/Rhinoceros-Iguana-2/
BY JOHN BINNS
Light and Heat Notes :
Proper lighting that simulates natural sunlight and the right temperature control are crucial for the rhinoceros iguana. Too often the cost of good lighting is circumvented by the use of substandard products or, worse, by eliminating some lighting altogether. Don’t economize!
PHOTO CREDIT: JOHN BINN.
Three primary lamps are usually needed to fill the rhino iguana’s basic lighting requirements: color-corrective, basking and UVB. Lamp wattages depend on enclosure size, but all lamps come in various wattages to cover most needs.
Please note that the type and number of lamps required is subject to variability. In some cases the basking lamp can be eliminated if the UVB lamp produces sufficient heat for basking. Or the color-corrective lamp can be eliminated, depending on enclosure size, if you’re using a UVB metal halide lamp. But this lamp must meet the following specifications. A metal halide with .5 percent UVB, 11 percent UVA and 88.5 percent visible light is as close as you’ll ever get to the solar proportions. It also must produce 70,000 lux (about what you see at 10 a.m.) at a distance of 11½ inches. The brighter and more complete light spectrum can have a direct effect on the reptiles’ specific and paraspecific immune system. I use the new Mega-Ray Metal Halide UVB Lamp. Larger enclosures may require additional color-corrective lamps or fluorescents.
The purpose of color-corrective lighting is to provide bright, white light (natural daylight) within a range of about 30,000 to 80,000 lux with a color temperature range of 4000 to 6000 Kelvin (the higher the better). Not recommended are household incandescent light bulbs that produce yellowish light (2800 to 3300 K). I believe the best lamps for color-corrective lighting are metal halides (HQI color-corrected type), and/or one with 5000 to 6000 K that has compact or linear fluorescent tubes.
For rhinos’ and other Cyclura iguanas’ UVB requirements, I use the Mega-Ray UVB lamp by Reptile UV. These lamps produce sufficient levels of UVB (290 to 305 nanometers). Always follow the manufacturer’s guidelines when setting up these lights.
Basking lamp options include halogen, mercury vapor and others. Selection and type is based on diameter of the basking area, its distance from the basking fixture, and wattage necessary to achieve the correct basking temperature.
A thermostat-controlled heat lamp may also be required to maintain the nighttime ambient temperature or to stabilize daytime ambient temperatures in large enclosures. I use the Mega-Ray 60-Watt Lightless Infrared Heat Projector, which projects more heat than a traditional 100-watt ceramic heat emitter.
Place the basking area at the far end of the iguana’s enclosure to allow for a temperature gradient (hot to cool zone). Depending on the UVB and basking lamp configuration, place the fixtures with reflectors next to one another directly above the basking area’s center. Set the UVB lamp at the height recommended by the manufacturer, and adjust the basking lamp’s height to produce a temperature of 106 degrees. It should be configured to create an invisible cone of UVB radiation and heat that is large enough to encompass the rhino’s entire body. A large, flat, smooth fieldstone beneath the lamps works well to radiate heat from below. The periphery around this area should remain clear of objects for one to two feet, so the rhino can select a position for optimal thermoregulation. Adjustable ceiling vents directly above the iguana’s basking zone help to evacuate excess heat, and a small fan could be added to evacuate stale air through clothes-dryer tubing leading to the outside.
The optimal daytime ambient temperature within the enclosure is 81 degrees (with an acceptable range of 75 to 88 degrees). The cool-zone temperature is about 10 degrees less, creating an optimal nighttime temperature of 70 degrees (or a range of 68 to 73 degrees). Rhinos should not be exposed to temperatures below 62 degrees for any length of time.
Rhino iguanas are creatures of comfort, and their enclosures should offer places to lie down and a retreat to sleep. In the cool zone, the floor should be flat and heat-absorbent.
Place food and water bowls, positioned so they are difficult to overturn, in the cool zone. Substrate is not recommended near any feeding location because rhinos can ingest small amounts of it, which can lead to intestinal impaction. Floor covering used in the enclosure can be newspaper, artificial turf or outdoor carpeting; all are products that are easy to clean and replace. Soil- or bark-based substrates are not recommended for partitioned rooms or indoor enclosures. They can be used outdoors, as long as the feeding area is free of them.
The adult rhino iguana diet shown on page 42 meets the lizard’s minimal to optimal nutritional requirements, and it contains a balance of calcium, phosphorous, plant protein and fiber based on the combination of plant foods per serving with a minimum calcium-phosphorous ratio of 2-to-1 and a plant protein level of 9 to 12.4 percent. Correct environmental temperatures are crucial to ensure proper digestion.
Captive Cyclura species tend to have limited opportunities to exercise. Always couple their diet with an exercise regimen to expend calories, build muscle and improve gut motility. Monitor the animal’s weight and health regularly, and modify the diet if problems arise. Suggested serving amounts will vary depending on the size of the iguana, but they should not lead to obesity. Take your rhino to a veterinarian regularly for health checkups and to have fecal samples analyzed.
Diets evolve as new information is acquired, and this diet is no different. Existing research clearly indicates that rhinos are almost exclusively herbivores that infrequently consume small amounts of animal matter. Ingested animal matter results in excessive levels of protein, which can cause obesity and renal disease. This leads to excessive fat pads lining the abdominal cavity and hepatic lipidosis (fatty liver disease). A high-protein diet also damages the lizards’ kidneys over time and can cause chronic renal failure. Because organ damage is permanent, animal matter is not considered in this diet.
Avoid using plants with no nutritional value or those containing excessive amounts of phosphorus, oxalates (which inhibit calcium binding) or goitrogens (which suppress thyroid function). Spinach, cabbages, broccoli, Brussels sprouts, corn, celery and lettuces fall into one of these categories to avoid.
Based on the diet and lighting recommendations in this feature, we dust CaribSea's Blue Iguana Cal-Stron calcium over the diet ingredients before mixing them one to two times per week (two to three times for juveniles). For vitamins we dust Rep-Cal Herptivite over diet ingredients before mixing them every two weeks (every week for juveniles). Dusting is based on the manufacturer’s recommendations.
Calcium and vitamins are best prescribed by a qualified Cyclura vet who can analyze the iguana’s health, diet and lighting to recommend an appropriate amount based upon the lizard’s needs. Many lizardkeepers dust with supplements too often or too little. Having a veterinarian’s input is essential to the animal’s health.
Ingredients and Preparation
Wash all food before preparation. All plant material must be free of pesticides and fertilizers. Avoid nursery plants; they are grown with pesticides not intended for consumption, and these cannot be washed off. Remove seeds or pits. After food is processed, mix in a large container until all the ingredients are well-distributed. Mixing helps discourage the iguana from picking out favorite items and leaving the rest.
Staple: Dandelion*, collard greens, mustard greens, turnip greens *Note: Dandelion is required but can be temporarily replaced (for one to two weeks) with any one of the other staple greens. Turnip is interchangeable with collard and mustard greens.
Garnish: Escarole, watercress, endive, chicory
Occasional: Chard, kale, bok choy, cilantro, parsley
Diet Preparation: Cut thin strips one-fourth inch wide. Cut long strips crosswise every 2 to 3 inches for adults and every 1 inch for juveniles.
Staple: Green beans, snap peas, okra, parsnip, yucca root, bell peppers
Occasional: Carrots, beets, sweet potatoes
Diet Preparation: Chop and then shred vegetables in a food processor.
Staple: Acorn, butternut, kabocha, pumpkin, spaghetti squash
Garnish: Banana, delicata, Hubbard, turgan, crookneck and yellow squash
Diet Preparation: Skin and remove seeds from all squash items before feeding. Using a food processor, grate all squash items.
Staple: Figs, dates, papaya, mango, cactus pads (prickly pear), cactus fruit (tuna fruit, much like prickly pear)
Garnish: Blueberries, raspberries, kiwi, acai berry
Occasional: Apples, bananas, blackberries, strawberries, grapes, nectarines, pears, cantaloupe, honeydew, watermelon
Diet Preparation: Using a food processor or sharp knife, finely chop all fruit items; apples can be shredded.
Sources: A high-quality, natural adult or juvenile food pellet without color dyes, such as Zoo Med and OxBow products made for iguanas. Alfalfa powder, leaf teas or pellets only; no loose or compressed hay.
Diet Preparation: Mix fiber and water (two-parts fiber to one-part water). If required, after the initial feeding, mist the food bowl to prevent excessive drying.
A special thanks to A.J. Gutman, Juliann Sweet, Melissa Kaplan, Jose Ottenwalder, Ernst Rupp, Thomas Wiewandt, Bob Powell, Bob MacCargar, Francis Baines and Sandy Binns for their efforts with this feature.
2- RHINOCEROS IGUANA
Cyclura cornuta cornuta
Adult Size: 2 to 4 feet.
Range: The island of Hispaniola.
Habitat: Woodlands and rocky areas.
Captive Lifespan: 12 to 20 Years
Care Level: Advanced
The rhinoceros iguana is one of the world's most magnificent iguanas. As its name implies, it is found on the island of Hispaniola. This species (as well as all other members of the genus Cyclura) are vulnerable due to their remote island habitats. Most Cyclura iguanas are listed as threatened or endangered.
The rhinoceros iguana is being kept in private collections in increasing numbers, and for good reason. Their large, impressive appearance make them a very desirable species to own. The disposition of this species can vary considerably. Some rhinoceros iguanas become extremely tame, while others can be extremely aggressive and inflict bites.
The rhinoceros iguana does best when housed in large, outdoor enclosures that allow it access to natural sunlight and high temperatures. A heated hidebox allows for thermoregulation during cool evenings and days. The rhinoceros iguana does best on a vegetarian diet consisting of collard greens, romaine lettuce, mustard greens, squash, parsley, figs, papaya and mango.
IGUANA -- Introduction
Please select or follow below :
IGUANA -- Introduction