How To Properly Heat Your Iguana Enclosure
Iguanas, like all cold-blooded animals, need heat in order to digest food, function and to boost their immune system. As poikilotherms, iguanas rely upon outside sources to warm and cool their bodies. Without the proper temperature gradients and adequate heat sources, your iguana will not be able to function properly and medical issues will arise.
Thermoregulation is the regulation of the iguanas internal body temperature. Since iguanas are cold-blooded and can not generate their own heat, they rely upon outside sources to help them complete this process. Iguanas are a basking species. They will lay outside during the day which offers them UVB exposure for dietary calcium absorbtion as well as to warm their bodies up enough to digest food and function properly. As the iguana reaches its desired temperature, it will move away from the source of heat warming and will then allow its body to cool. When their body begins too cool too much, they will return to the heat source and repreat the process. This is exactly how thermoregulation is performed in iguanas.
A heat gradient is when one area of the enclosure is a certain temperature and the other end of the enclosure is either higher or lower than the first. Since these 2 locations vary in temperature, the space between these 2 areas will have a gradient of heat indexes ranging from the lowest sides temp up to the warmer sides temps. This gradient of temperatures typically consists of the basking spots temperature, which is the warmest in the enclosure down to the lowest and safest temperature your iguana should be subjected to. These mico-climates will allow your iguana the ability to choose what temperature will help him thermoregulate the most efficiently at that point in time.
During the day you will want to create a heat gradient bewteen 80° - 88°. This does not include the basking zone, which will be warmer. We are referring to the ambient temperature in the enclosure. You should have at least 2 digital thermometers with probes monitorig the temperatures. You don't want to fall below 80°.
in the wild, as the sun goes down, so too do the temperatures. This should also be the case in your enclosure. Iguanas do well with a temperature drop between 75° and 78°. You don't want to go cooler than 75° and exceeding 78° would bring you back to the low gradient of the day.
Iguanas require a basking zone. Normally the basking zone is the highest point that the iguana can reach in his or her enclosure. It is no closer than 6-8 inches and no less than 12 inches to the lighting and heating fixtures and is very stable. (The distance will be determined by the temperature and UV checks you do.) The size of the basking zone depends upon the size of your iguana. It should be large enough that your iguana can stretch out and soak his or her entire body under the heating and lighting fixtures. This is where your iguana will spend most of its time and this is where the primary ultraviolet lights (UVB emitting) should be set. You should place a digital thermometer (with probe) within the enclosure around the basking zone and maintain the ambient temperature around 90°-95° F. Exceeding these temps could cause the enclosure to dry out rapidly. The thermometer and temp gun above are the tools I use to maintain my reptile enclosure temperatures.
The basking zone temperature, or the surface temperature of the iguana laying in the basking zone, should be maintained between 100° and 110°. These temperatures should be measured using a temperature gun. Temperatures in the basking zone need to be measured from the animals body and not by the shelf they will be laying on. The temperature could be perfect on the shelf but could be substantially hotter on the iguanas back, since the animal is made of mass and will be physically closer to the element that what the shelf is.
Daytime heat can be provided using flood lamps, ceramic heat emitters, self-ballasted mercury vapor lighting, household bulbs, etc. There are several options at your disposal. Nighttime heat can be a bit more difficult to supply because you don't want to interfere with the animals photoperiod. Ceramic heat emitters are great for supplying supplemental heat because they don't produce light and come in different wattages, producing different levels of heat. Heat rocks ARE NOT proper heating equipment and should NOT be used. Read more on why heat rocks are dangerous on our Heat Rocks - Hidden Dangers page.
All of your heating and lighting equipment should be placed on timers to ensure your iguana is given a stable and reliable routine. Keeping everything on timers removes the chance that you will forget his lights or heaters when life gets busy. You should also be using several digital thermometers to monitor and regulate the temperatures.
Author: Richard Brooks