The common iguana can reach 80 inches in length, and its cage must grow as it does. Don’t overcrowd them! Three juveniles (one male and two females) will need a cage 48”x 24”x 24”. Iguanas are aboreal (tree dwellers), and are best kept in cages with several branches for them to climb. The branches should be at least the size of the iguana’s torso. Plants should not be used; many are poisonous and none will survive in the iguana’s cage. Newspaper makes the best substrate, as it is easy to clean.
The common iguana is native to the savannahs and rain forests of southern Mexico and Central and South America, and does best in a humid environment. ULTRAVIOLET LIGHT IS A MUST FOR YOUR IGUANA! Without it, they cannot assimilate certain vitamins, including the most important D3, which are vital. (Note that ultraviolet light can not pass through glass or plastic adequately. Keep this in mind when setting up the cage.)
Provide a water bowl big enough for bathing, and change the water daily. The larger the bowl, the better. Iguanas often enjoy bathing, and a large bowl will increase the humidity. If you keep your iguana in a screen topped aquarium, cover most of the screen with plastic to hold in the humidity.
Iguanas are ectothermic, meaning they need an outside source of body heat. Without this they will not feed, digest, or reproduce. Optimum daytime temperatures should be between 80 and 90 degrees F with a basking spot of 95-100 degrees F. Set up your heating units (ceramic heating elements, heating pads, basking lights) so that one end of the cage is warmer than the other, giving your lizard a temperature gradient. A thermometer should be kept in the warm end of the cage to assure that you maintain a good temperature. To keep humidity high enough, use an air humidifier, or mist the animal several times a day with warm water from a plant misting bottle.
Iguanas, juveniles and adults are totally herbivorous. A diet made primarily of dark, leafy greens is vital to the health of your lizard. This diet will prevent kidney damage which can cause premature death. The diet should be rotated with vegetables; collard greens, mustard greens (including flowers), broccoli rabe (the leaves are very high in calcium), red leaf lettuce, escarole, dandelion greens, chicory, Swiss chard, fruits; apples and bananas, cantelope, kiwi fruit, legumes; green beans, and peas. Give your iguana a variety of foods. Juveniles should be fed daily, adults daily or every other day. Sprinkle the food with a vitamin powder such as Rep-CalTM once or twice a week. The supplements are very important in preventing irreparable damage to your animal’s health. Vegetables such as broccoli (regular, not rabe), spinach, kale and carrots should be fed infrequently as they contain calcium oxalic acid which binds calcium and prevents absorption by the animal of this very important mineral.
Cages must be kept clean to prevent mites, scale rot, and other problems. Anti-bacterial cleaning solutions are recommended. One ounce of bleach in ten ounces of water is one such solution. Rinse the cage with clean water after using any solution. Don’t use Lysol, Lestoil or other such oil-based cleaners; they are deadly to reptiles.
You’ll find that your iguana has very sharp claws. See your veterinarian or ask the pet shop how to trim them. Your iguana does not require petting, but may enjoy sitting on your lap for warmth and comfort. They seldom bite, but if you are bitten, check with your doctor for proper treatment.
Male iguanas may become aggressive when they become sexually mature. Understanding their behavior and planning ahead can help you both get through this sometimes trying time. For most male iguanas this is only a periodic change of personality and once the breeding season is over, they usually return to ‘normal’.