Vivariums;reptiles;Desert iguana

From Wikipedia, the free encyclopedia

The desert iguana (Dipsosaurus dorsalis) is one of the most common lizards of the Sonoran and Mojave deserts of the southwestern United States and northwestern Mexico. They also occur on several Gulf of California islands. Their color is mostly grey and tan.

Desert iguana

Conservation status :

Least Concern (IUCN 3.1)[2]

Scientific classification :

Kingdom:Animalia

Phylum:Chordata

Class:Sauropsida

Order:Squamata

Suborder:Lacertilia

Family:Iguanidae

Genus:Dipsosaurus
Hallowell, 1854

Species:D. dorsalis

Binomial name :

Dipsosaurus dorsalis
(Baird and Girard), 1852

Taxonomy :

The species was first described in the Catalog of North American Reptiles, by Spencer Fullerton Baird and Charles Frédéric Girard, in 1859 as Crotaphytus dorsalis it was reclassified two years later as Dipsosaurus dofus dorsalis by Edward Hallowell.[3] The generic name comes from a combination of two Greek words meaning "hungry lizard": "Dipsa" (δίψα) for "thirsty", and "sauros" (σαῦρος) for "lizard". The specific name, "dorsalis", comes from the Latin word dorsum meaning "spike", in reference to a row of enlarged keeled scales on the middle of the lizard's back which form a crest that extends almost to the tip of its vent. Dipsosaurus is a monotypic genus with D. dorsalis being its only recognized species.

Description :

The desert iguana is a blunt, medium-sized lizard which grows to 61 cm (24 in) including the tail.[4] They are pale gray-tan to cream in color with a light brown reticulated pattern on their backs and sides. Down the center of the back is a row of slightly-enlarged, keeled dorsal scales that become slightly larger as you move down the back.

The reticulated pattern gives way to brown spots near the back legs, turning into stripes along the tail. The tail is usually around 1½ times longer than the body from snout to vent. The belly is pale. During the breeding season, the sides become pinkish in both sexes.

Habitat :

Their preferred habitat is largely contained within the range of the creosote bush, mainly dry, sandy desert scrubland below 1,000 m (3,300 ft). It can also be found in rocky streambeds up to 1,000 m. In the southern portion of its range this lizard lives in areas of arid subtropical scrub and tropical deciduous forest.

These lizards can withstand high temperatures and are out and about after other lizards have retreated into their burrows. They burrow extensively and if threatened will scamper into a shrub and go quickly down a burrow. Their burrows are usually dug in the sand under bushes like the creosote. They also often use burrows of kit foxes and desert tortoises.

Desert Iguana in the Wild

Diet and reproduction :

Mating takes place in the early spring. It is believed that only one clutch of eggs is laid each year, with each clutch having 3-8 eggs.[5] The hatchlings emerge around September.[5]

Desert iguanas are primarily herbivorous, eating buds, fruits and leaves of many annual and perennial plants.[5] They are especially attracted to the yellow flowers of the creosote bush.[5] Predators of these iguanas and their eggs are birds of prey, foxes, rats, long-tailed weasels, some snakes, and humans.[5]

For the external links , refrences click here to read the full wikipedia article

Video :

Other Websites :

- ipfactly.com/desert-iguana/

- www.lizardtypes.com/desert-iguana/

- www.reptilesofaz.org/Lizards-Subpages/h-d-dorsalis.html

- www.californiaherps.com/lizards/pages/d.d.dorsalis.html

- www.iucnredlist.org/details/64053/0

- www.desertusa.com/reptiles/desert-iguanas.html

- reptile-database.reptarium.cz/species?genus=Dipsosaurus&species=dorsalis

Care Articles :

- Desert Iguana Care Sheet

courtesy to : www.reptilesmagazine.com/Care-Sheets/Desert-Iguana/

BY ROBERT GEORGE SPRACKLAND, PH.D.

The desert iguana can be very hardy in captivity if given proper care.

ROBERT GEORGE SPRACKLAND

Desert Iguana (Dipsosaurus dorsalis)

A large, somewhat cylindrical, long-tailed lizard with well-developed legs, eyelids and ear openings, and the only U.S. native lizard with a vertebral row of enlarged dorsal scales. The head is comparatively short and round. Coloration is primarily light gray to white; dorsoventrally there is a “vest” of darker gray with white, brown, and often red markings. The tail is primarily very light gray or white with dark brown spots that form broken bands. Ventrally unpatterned. Both sexes may be light pink ventrally, but more commonly the belly and lower flanks are very light gray. Sexual dimorphism minimal; males generally have enlarged femoral cones during the breeding months. Females lay up to 8 eggs per clutch, with one annual clutch the norm. Hatching occurs after 60 days. Life span may exceed 14 years.

These lizards can be very hardy in captivity IF given proper care. Successful terrarium maintenance, reproduction, and rearing of desert iguanas is linked to four indispensible factors. First, they require very high temperatures that exceed 33 C (90 F), because high heat is essential for digestion of foods and maximal development of incubating eggs. Second, they need considerable bright light, which enhances normal behaviors and promotes more rapid growth. Third, desert iguanas must have a varied diet of vegetable matter that supplies the nutrients and water content they need. They are so fine-tuned to processing the ion concentration found in their diets that mineral supplementation is not advised. Finally, they require large terraria with a deep sandy substrate, with no more than one male per enclosure.

ROBERT GEORGE SPRACKLAND

A desert iguana peeks out of its hole.

Scientific Name: Dipsosaurus dorsalis (Baird and Girard, 1852)
Family: Iguanidae
Adult Size: 16” average; 18” maximum
Wild Range: Southwestern United States (S. California, Arizona, Nevada, Utah) and northwestern Mexico (Baja California, Sinaloa, Sonora)
Wild Habitat: Creosote bush desert with hummocks of loose sand and scattered rocks; subtropical scrub habitats around sparse vegetation and low brush

ROBERT GEORGE SPRACKLAND

In captivity, feed desert iguanas a range of diced fruits and vegetables, including corn, tomatoes, berries, oranges, squash, pumpkin, sunflower seeds, sesame seeds, and small nuts.

Availability

Desert iguanas are not readily available through dealers, though they do show up on stock lists on rare occasions. You are more likely to acquire specimens by searching the various online postings from individuals who already have desert iguanas and want to sell them or their hatchlings. They may also be legally collected in Nevada and, provided you have proper permits, in the other states where they occur. The best time to look for lizards is May through late August, in the early morning or late afternoon.

Size

Hatchlings measure 5 to 5.3 inches in total length. If well fed and given proper lighting conditions, they may grow by about an inch (snout-vent length) per year. Young have a more intricate pattern than adults, often with considerable yellowish on the head, spine, and sides. Adults reach a maximum total size of 18 inches.

Life Span

The record lifespan for wild desert iguanas is just over seven years. A captive male, who was nearly adult size when acquired, lived for a bit over 14 years; presumably, he was as much as 17 years old.

Caging

A pair of adult desert iguanas may be adequately house in a terrarium 3 ft by 2 ft, and 2 ft high. If more than two lizards are to be kept together, the terrarium should be much larger; for three or fours adults, provide floor space of at least 4 ft by 4 ft, but I strongly recommend using 6 ft by 3 ft. The viewing area should be made of glass, because desert iguana claws will scratch plastic, and the lizards are very prone to rubbing their snouts raw against screen. A screen top is advised. Desert iguanas require large terraria with a deep sandy substrate (I suggest 10-12 inches), with no more than one male per enclosure. They may be safely housed with similar-sized hot desert species, such as Chuckwallas.

Lighting and Temperature

Successful terrarium maintenance, reproduction, and rearing of desert iguanas is linked to two indispensible factors regarding light and heat. As stated previously, they require very high air temperatures that exceed 33 C (90 F), because high heat is essential for digestion of foods and maximal development of incubating eggs. Preferred temperatures range from 33 to 41 C (90 to 105 F). Use of heat lamps and under-terrarium heat pads is essential. There must also be areas, including burrows, where the lizards can move to escape both intense heat and direct light. They also need considerable bright light, which enhances normal behaviors and promotes more rapid growth. Several studies have shown that desert iguanas grow more quickly, to a larger size, and attain better health if exposed to bright light for at least 12 hours each day. Humidity should range between 15% and 30% except after brief periodic misting of the terrarium.

Substrate :

Almost any clean sand will do fine as substrate. It must be very slightly moist, just enough so that burrows can be dug without immediate cave in. Sand should be lightly sprayed from time to time to keep moisture levels.

Food :

In captivity, feed desert iguanas a range of diced fruits and vegetables, including corn, tomatoes, berries, oranges, squash, pumpkin, sunflower seeds, sesame seeds, and small nuts (unsalted). Some moist leafy lettuce should be included as a water source, because Desert Iguanas do not drink reliably from water dishes. Though they do eat termites, ants, and small beetles on occasion, insect prey represents an extremely small percentage of the natural diet, and need not concern the keeper. As herbivores, desert iguanas must eat more bulk, more often, and take longer to digest food than non-herbivorous lizards, so be sure they have some food available daily. They will not over-eat, so providing excess food is resolved only by removing what the lizards leave behind. They should not be given potassium supplements.

ROBERT GEORGE SPRACKLAND

A desert iguana in its natural habitat.

Water :

Some moist leafy lettuce should be included as a water source, because Desert Iguanas do not drink reliably from water dishes. However, a small dish of clean water should always be available.

Handling and Temperament

Desert iguanas are fairly docile animals that become accustomed to gentle handling. Freshly captured and very warm individuals may bite, and can break the skin.

Reproduction and Breeding

Mated females may lay up to eight nearly round eggs, usually in a nest she excavates in the sand. Deposition sites are made of slightly moist soil in places where the subsoil temperature will stay between 28 C and 38 C (82 F and 100 F). Unlike refuge burrows, which are generally under plant cover, nests are excavated in areas of sparse or no vegetation, presumably because the roots would alter the soil water content to the detriment of the eggs. In the wild, they take 60 to 75 days to hatch, with incubation time reduced at the higher temperatures. Hatchlings tend to be 50 to 60mm (5 to 5.3 inches) in total length, and may grow at a rate of 22mm per year, snout-vent length. Thus, they tend to grow and mature quickly, reaching reproductive size in about 33 months. Lizards grow more rapidly, and to larger size, in wetter years than dry ones.

Hatchlings may be safely housed together for a few months, but should be separated before males begin to attack each other. House and feed them as you would the adults.

References:

- Blázquez, M.C. and Ortega-Rubio, A. 1996. Lizard winter activity at Baja California Sur, Mexico. Journal of Arid Environments 33: 247-253.

- Carpenter, C. C. 1961. Patterns of social behavior in the desert iguana, Dipsosaurus dorsalis. Copeia 1961:396-405.

- Degenhardt, W. G., C. Painter, and A. Price. 1996. Amphibians and Reptiles of New Mexico. University of New Mexico Press. Albuquerque.

- Dibble, C.J., G. Smith, and J. Lemos-Espinal. 2008. Diet and Sexual Dimorphism of the Desert Iguana, Dipsosaurus dorsalis, from Sonora, Mexico Western North American Naturalist 68(4):521-523.Grestle, J., and I. Callard. 1972. Reproduction and estrogen-induced vitellogenesis in Dipsosaurus dorsalis. Journal of Comparative Biochemical Physiology 42A:791-801.

- Grismer, L. 2002. Amphibians and Reptiles of Baja California, including its Pacific Islands and the Islands in the Sea of Cortés. University of California Press, Berkeley, California.

- Hallowell, E. 1854. Descriptions of new reptiles from California. Proceedings of the Academy of Natural Sciences of Philadelphia, 7: 91-97.

- Harlow, H. J., S. Hillman, and Hoffman. 1976. The effect of temperature on digestive efficiency in the herbivorous lizard, Dipsosaurus dorsalis. Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology 111(1): 1-6.

- Hazard, Lisa. 2001. Ion Secretion by Salt Glands of Desert Iguanas (Dipsosaurus dorsalis). Physiological and Biochemical Zoology, 74(1): 22-31.

- Hulse, A.C. 1992. Dipsosaurus dorsalis. Catalogue of American Amphibians and Reptiles 542: 1-6.

- Ivanyi, C. 2004. The Desert Iguana. Reptiles 12(10): 30-43.

- Krekorian, C. O. 1984. Life history of the desert iguana, Dipsosaurus dorsalis. Herpetologica 40(4): 415-424.Krekorian, C. O. 1976. Home-range size and overlap and their relationship to food abundance in the desert iguana, Dipsosaurus dorsalis. Herpetologica 32:405-412. Macey, J. R. and T. J. Papenfuss. 1991. Reptiles. Pages 291-360 in C.A. Hall, Jr., editor. Natural History of the White-Inyo Range eastern California. University of California Press, Berkeley, California. Mayhew, W. 1971. Reproduction in the desert lizard, Dipsosaurus dorsalis. Herpetologica 27:57-77. Moberly, W. 1961. Hibernation in the desert iguana, Dipsosaurus dorsalis. Physiological Zooogy. 36:152-160. Muth, A. 1980. Physiological ecology of desert iguana (Dipsosaurus dorsalis) eggs: temperature and water relations. Ecology, 61(6): 1335-1343.

- Muth, A. 1977. Eggs and hatchlings of captive Dipsosaurus dorsalis. Copeia 1977: 189-190. Norris, K. S. 1953. The ecology of the desert iguana Dipsosaurus dorsalis. Ecology 34:263-287. Pianka, E. R. 1971. Comparative ecology of two lizards. Copeia 1971:129-138.

- Sprackland, Robert. 2010. Pocket Expert Guide to Lizards: 300+ Essential Species. TFH Publications, Neptune, NJ.Stebbins, R.C. 2003. A Field Guide to Western Reptiles and Amphibians, Third Edition. Houghton Mifflin Company, Boston, MA.

Reader Comments:

APR 3, 2016 01:59 PM

POSTED BY ANONYMOUS

Some good information on a still very underrated lizard here. There's an impressive reference list as well, so I'm not claiming to know better, just offering another opinion / experience. The following is just my own opinion. The only points I would offer a different opinion on are:

The hot spot / basking temperature can be 50 C - these lizards are known to be out in temperatures above that when most other reptiles have hidden away. No doubt this plays a part in their survival.

I would stay away from a focus on fruit and nuts and try to replicate the tough, fibrous plants they eat in the wild - look at uromastyx feeding guides - and stay away from citrus fruits. You need to do your own research to be happy with your feeding plan, but you could start with spring greens, runner beans, sugar snaps etc, cactus pads, pak choy, squash, chicory etc. When feeding fruits, which should be a much smaller part of the diet, try feeding the skins and leaving the flesh out.

Co-habiting with other species is always up to the owner, and causes much debate. However, I believe the idea of desert iguanas and chuckwallas sharing space has largely come from examples in zoo collections, which have extremely large enclosures able to give these reptiles space to keep away from each other. The average hobbyist does not have a vivarium large enough to allow that to happen.

The size of the vivarium is usually recommended to be much larger then mentioned here. A 4 x 2 x 2 foot is fine for a single lizard, with 5 x 2 x 2 a minimum for a pair. The more the better as these are very active lizards that need to be given opportunities to run, jump and climb, as well as move around to find temperature spots.

The idea of spraying does make sense as a way of offering drinking water, but I feel that the point is over stated here. If fresh vegetables / leaves are offered, the lizard will gain its moisture from those. If a bowl of water is kept in the viv, it needs to be small and in the cooler end. Regular spraying will create a high humidity which these lizards do not need. Again, look at advice for uromastyx, for which there seems to be more available info. As creating moist, dig-able sand without a moisture issue can be difficult in the average viv, I would suggest just offering dry substrate with a few secure hiding spaces (plastic hides, bark, rocks etc).

Lastly, I would like to say that, in over a decade, I have never been bitten by a Desert iguana. If they are wild caught, the are likely to be flighty, and may stay that way. I have experienced both ends of the spectrum, with a male being happy to walk onto my hand and take food from me, and a female that bolted very time I opened the door. Still, no biting. If scared, they will run, which they can do very well.

Videos :