The green (or common) iguana (Iguana iguana) is an arboreal (tree-living) and diurnal (daylight- active) lizard usually found at elevations below 3,000 feet in tropical and subtropical regions from northern Mexico to central South America. It is most often found in the vicinity of rivers and streams.

Iguanas have short, powerful limbs equipped with strong, sharp claws (for climbing and digging), and a long, strong tail. They can reach lengths of 6-6 1/2 feet. A large flap of skin (the dewlap)hangs from the throat and helps regulate body temperature. Iguanas also have a prominent crest of soft spines (longer in males) along the midline of the neck and back, beginning at the base of the skull. Male iguanas tend to be larger and have brighter overall coloration than females. The distinct color of males is especially pronounced during the breeding season. Males tend to have larger heads than females, in part because of swollen jowls. Both sexes have 12-13 prominent pores arranged in a row on the underside of both thighs. These glandular structures secrete a waxy substance with which iguanas mark their territory and identify each other. As the males mature, their “femoral pores” develop slight outward projections. This developmental modification probably enables the male to better grasp the female during copulation. An iguana’s skin is entirely covered with very tiny scales. Iguanas cannot change their coloring (as chameleons do), but certain areas of the skin can become darker when exposed to direct sunlight.

Young iguanas are pale green with black-ringed tails. They mature to a lighter, more earthy color, usually with dark vertical bars on the body and tail. Vision, hearing and the sense of smell are acute. In their natural environment, iguanas tend to be very wary, hiding or fleeing at any sign of danger. Iguanas are somewhat clumsy but accomplished tree climbers. They tend to bask by day on tree branches, often over water. When frightened or threatened, they usually drop (sometimes from great heights) into the water below. Being excellent swimmers, they quickly make their way to protective cover by pressing their front limbs along their sides and swishing their powerful tails from side to side. Iguanas can also safely land on the ground and run to protective cover after jumping from substantial heights. When threatened or cornered, iguanas can defend themselves with astonishingly quick, whip-like lashes of their tails and with their claws and jaws. Iguanas mate in January or February. After a pregnancy of about 2 months, the female digs in moist sand or soil, usually near the base of a tree, and deposits 25-40 eggs. The hatchlings, measuring 25-30 centimeters long, emerge in about 2 weeks. They grow 15-24 centimeters a year and attain sexual maturity in about 3 years. An interesting, but unfortunate, fact is that the iguana is widely hunted throughout its range for its tender white flesh and for its alleged aphrodisiac properties. Central American natives refer to the green iguana as “bamboo chicken”. Because it is timid and relatively slow, it is easily captured. Its eggs are also collected and eaten by local hunters.

REQUIREMENTS IN CAPTIVITY:

In its natural environment, the green iguana is almost completely herbivorous (plant-eating) from the time it hatches. Despite this, captive juvenile iguanas should be fed a relatively large proportion of animal protein. Older iguanas should receive a greater proportion of vegetable matter in their diets. Juvenile iguanas should be fed daily. A good diet consists of 15% part animal protein (water- packed tuna, cooked chicken, hard-boiled or scrambled egg, Purina Trout Chow, dog food) added to 75% parts vegetable material (broccoli and its leaves, Swiss chard, spinach, alfalfa sprouts, beet, collard, mustard and turnip greens, carrot tops and thawed, frozen mixed vegetables timothy hay, rape, and dandelions) 10% fruits include figs (are best), others include apples, apricots, dates, grapes, and raisins. Chop all of the ingredients into a size that can be easily handled by the young iguana. Then mix them thoroughly and store the mixture in the refrigerator in an air-tight container. Once or twice a day, offer a small amount of this mixture after it has been liberally sprinkled with an appropriate vitamin-mineral supplement (We highly recommend the following products: Repcale, Reptical, and Nutrogro, Vita-Life, Terra-Fauna Products, Reptovite, Verner’s Pet Products, from pet stores and Nekton-Rep (from Germany) and other Nekton products which may be available for sale in some veterinary hospitals. Also if you subscribe to any of the herpetology magazines, these products or newer ones may be available. Particular attention to calcium supplements is essential because young, growing iguanas are very prone to calcium deficiencies. Again, Nutrogro will satisfy these requirements. Nekton-MSA, Reptical or Vita-Life may also be used to supplement all juvenile iguanas. Growing iguanas may also be fed “expanded” guinea pig or rabbit pellets (pellets allowed to expand by absorbing water), either plain or as a top dressing over vegetables. This is a convenient way to add necessary vitamins and minerals (contained in the pelleted food) to the iguana’s diet.

This is some newer information I recently received updating feeding of the green iguana. Again, this just shows the changes that are occurring regarding care of iguanas.

“Iguanas should not at any age be fed that much protein!   The green iguana (iguana iguana) is one of the relatively few species of lizards living soley on a diet of vegetation throughout its life…. The natural diet of the green iguana consists of leaves, flowers, and fruits.             _”Digestion in an Ectothermic Herbivore, the Green iguana (iguana iguana)”           

A correct diet is as followed.  1-3% supplementary protein.  0-4% Grain-based foods.  10-15% fruits.  30-40% other veggies (beans, squash, zucchini, etc…).  30-45% leafy greens (collard greens, mustard greens, dandelions, endive, escarole, turnip greens, etc…).  Any kind of meat is not real food for an iguana.  Chows are a commercial food formulated for other species.  These are high in protein, vitamin D, and fat.  Iguanas often grow very quickly when given too much protein, but their life span is considerably shorter.  It is not uncommon for iguanas to live in excess of 15 years.  I got all of the info from a gook called Green Iguana The  Ultimate Owner’s Manual.   By James W. Hatfield III.  “

Older iguanas should be fed 2-3 times per week and can be offered the same items as listed above. The percentages should change. They should be fed 85% dark leafy greens, 10% fruits, 5% protein. Feeding live food such as crickets, meal worms, and pinkies we feel may lead to the transmission of parasites. Again, plant material, such as dandelions (flowers and leaves), clover, rose petals, and flowers of hibiscus, carnation and nasturtium, should be offered as well. Many health food stores carry dried dandelion and other edible herbs that can be offered to captive iguanas all year round. Fresh fruit (figs, dates, bananas, berries, apples, peaches, pears, plums) can occasionally be included in the diet.

If a captive iguana is to be fed and benefit from live insects (crickets, mealworms), careful attention must be paid to how these insects are reared and fed before they are offered as prey. Mealworms, for example, are often reared in wheat middling and/or wheat bran, which are calcium deficient. Mealworms nourished on such calcium- poor material consequently become calcium- deficient and so, too, will iguanas feeding on them, often resulting in metabolic bone disease.

Ideally, you should rear all insects destined to be fed to your iguana on a poultry laying ration (usually containing 8-12% calcium) for at least 1 week before they are sacrificed. Add slices of sweet potato to the mealworm or insect container to provide necessary moisture. Crickets and mealworms may also be lightly sprayed with an aerosolized vegetable oil and then dusted with a vitamin-mineral supplement just before they are offered to the iguana.

Intestinal Inoculation :

A fairly recent discovery has provided a probable explanation for the premature deaths of young iguanas despite apparently adequate diets. In the wild, young iguanas obtain needed intestinal bacteria and protozoa by eating the feces of adult iguanas. The micro- organisms acquired this way are essential for digestion of plant material. Baby iguanas are not born with these microbes, so young iguanas reared in captivity never acquire them.

All newly acquired, domestically raised (not wild- caught) iguanas should receive fresh feces from a healthy, parasite-free adult iguana (preferably wild-caught). One dose should inoculate the iguana for life. Some veterinary hospitals are prepared to assist new iguana owners with this process.

Hygiene:

Next to adequate nutrition, no other aspect of husbandry for captive reptiles is more important than sanitation and hygiene. Many bacterial and fungal diseases of captive reptiles result from their daily exposure to fecal contamination and a damp, filthy environment.

In the wild, reptiles have acres of land and water over which their feces and uneaten food can be scattered. They rarely, if ever, come in contact with this material. This is not the case with captive reptiles. Owners of captive reptiles engage in a continual struggle to prevent bacterial build-up caused by continual deposition of waste products and uneaten food.

An iguana’s cage floor or aquarium bottom can be covered with clean newspaper (unprinted preferably) or butcher paper. The next best material is indoor-outdoor carpeting. Paper towel squares can also be placed end to end to cover the entire bottom of the enclosure. When one of the squares becomes soiled, it can be easily removed and replaced without disturbing the entire floor of the enclosure. Under no circumstances should pea gravel, corncob material, wood shavings, sand, kitty litter or sawdust be used. None of these items promote adequate cleanliness, and they may be eaten while the iguana is feeding, resulting in intestinal impaction.

Iguanas are frequently displayed on moss. Even though this is visually attractive, it is a poor husbandry practice because this material remains continually damp, promoting serious skin infections.

A captive iguana’s environment must be kept fastidiously clean and dry. Any object that becomes soiled with feces or urine should be removed and cleaned or replaced as soon as possible. The enclosure should be set up so that it can be easily cleaned. Human nature dictates that the more time it takes to clean the cage and the more complicated the task, the less often it will be done. Make the enclosure functional rather than beautiful.

Reptiles are highly susceptible to poisoning from pine oil cleaners, such as PineSol and Lysol. These household cleaners must be avoided.

Visual Security:

A hiding place into which a captive iguana can retreat and be free from constant visual scrutiny should be provided. Visual security can be provided by supplying cardboard rolls (from toilet paper or paper towels) for small iguanas or cardboard boxes for large iguanas. Optimal visual security can be provided, however, by strategic placement of artificial plants. Because iguanas like to climb and bask, some of the branches and artificial plants provided should be arranged to allow this activity above the floor of the enclosure. Silk artificial plants are visually pleasing and easy to clean and maintain, and also withstand the use of disinfectants.

Focal Heat Source:

All reptiles require a warm environmental temperature to raise their body temperature and increase their metabolic rate and activity level. The optimal environmental temperature to provide for captive iguanas in their enclosures is between 85 and 103 F.

In the wild, reptiles bask in direct sunlight. Captive iguanas do quite well when a 60-100 watt light bulb with a reflector is placed outside the cage or resting area on the screen. Also, a small infrared light (make sure it is at least 18″ from the iguana). A space heater in the area is also useful to maintain the ambient temperature. Less desirable are “hot rocks” (Sizzle Stone, Terra Fauna Products) is provided. Here the iguana has the option of lying on this object (totally or partially) to obtain its heat as needed. But care must be taken to ensure the appliance is functioning properly. Malfunctioning hot rocks can cause serious burns.

Sunlight and Artificial Sunlight:

Captive reptiles rarely receive adequate exposure to ultraviolet (UV) light, especially when they are housed indoors. Captive reptiles, especially iguanas, must receive direct sunlight to benefit from its UV component. Ultraviolet light is necessary to properly absorb dietary calcium.

Window glass and plastics filter UV light. Consequently, reptiles must be housed in screened or wire enclosures during the time they are to be exposed to direct sunlight. Also, a shaded area must be provided so the iguana can avoid heat stroke from over- exposure to sunlight.

An alternative to direct sunlight for reptiles house indoors is an artificial two light source. A UV light such as a Vitalite (Duro-Lite Lamps, Lyndhurst, NJ 07071) as well a a black light are necessary. To approximate a natural photoperiod, it is best to supply 10-12 hours of daylight and 12-14 hours of darkness each day, with a gradual increase in the number of hours of light supplied in the spring and a gradual decrease in the number of hours provided in the fall and winter months.

Water :

Water can be made available to captive iguanas in a variety of ways. A standing water source, such as a filled ceramic dish, can be available for bathing and drinking. Spraying water on artificial plants and allowing the iguana to lap up this moisture is another suitable strategy.

The bathtub is a wonderful and practical recreational area for a pet iguana. Swimming is great fun to observe and provides excellent exercise for the iguana. The tub is also a practical, relatively escape-proof “holding area” for the iguana while its enclosure is being cleaned. The tub should be filled so that its shallowest portion allows for submersion of about 2/3 of the iguana’s body. The water should be warm and of a temperature comfortable for a human bather. Iguanas may be allowed to occasionally swim in chlorinated swimming pools as long as the activity is closely supervised and the iguana is thoroughly rinsed off with fresh water afterwards.

Cage Mate :

A cage mate for an iguana is not advisable. Iguanas are not particularly sociable animals and are quite territorial. The addition of a cage mate invites unnecessary aggression and fighting.