The Nile Monitor (Varanus niloticus)Species Information:The Nile Monitor (Varanus niloticus) is an easily obtained lizard species sold in the pet trade. The Nile monitor (Varanus niloticus) is represented by two separate sub-species, Varanus niloticus niloticus, and Varanus niloticus ornatus. Both of these sub species are fully acknowledged in American herpetology, although several other sub-species may be better classified in other countries (especially the European community). Even though they are one of the more easily obtained species, this should be no indication to their suitability for captivity. Some individuals may become more docile with time and an investment in proper care, which includes frequent and gentle handling. The Nile monitor is the largest lizard in Africa, and ranks as the second largest reptile on the continent, with the Nile crocodile being the largest. The Nile monitor ranges throughout much of the continent, with most imported species coming from Kenya or Nigeria. The Nile monitor is semi-aquatic, therefore being found around rivers, or other bodies of water. After the decision has been made that a Nile monitor is the species that you desire to keep, the next important step is to further one's knowledge in order to become a more responsible keeper. While not recommended for the novice herpafauna keeper, there is sufficient information available to make the experience much easier.Size and Longevity:Upon hatching Nile monitor babies will be between 7 and 12 inches in length. If fed sufficiently and cared for properly, hatchlings grow rather quickly. Adults can obtain lengths of 6 feet, with claims of specimens reaching 8 feet having been reported. Captive specimens tend to be quite heavier than they would be in the wild. The tail represents approximately 50-65 % of the animals overall length. As with other monitor species of similar size, the Nile monitor can live to be up to 30 years of age, given proper care. The responsible keeper should make sure that they have an acceptable plan of action, for the entire animals life. As with other reptiles, the rate at which your Nile monitor will grow depends entirely upon how much, and how frequently it is fed, and the percentage of protein in the specific diet. As in other varanid species, the males tend to be noticeably larger than females of the same species. It has also been observed that males also have a tendency to grow at a faster rate than females.Habitat / Caging Requirements:One should first make sure that prior to receiving their pet Nile monitor, that they first have an appropriate setup in which to keep it. For optimal lizard health, it is best to provide them with a naturalistic environment. Attempting to replicate the animals natural habitat will significantly decrease the stress that your animal experiences. Stress is one of the main causes of premature death in captive animals. It is estimated that among imported animals, as many as 60-70 % die before being able to be placed into a new home. Of the remaining 30-40%, a large number of them meet their fate from improper housing in wholesale pet trade environments. In an effort to insure conservation, it is the responsibility of every person, to ask where their animals come from, and what type of environment they are kept in. Doing this, prior to purchasing a new animal, can help to insure that the individual animal they are receiving is in the best health, both physically as well as mentally.Being semi-aquatic, the Nile monitor should have an ample opportunity to at very least immerses itself in clean water. If at all possible one should provide a large enough aquatic area that the lizard may swim in it. Many varanids, including Nile monitors, will defecate in water if given a chance to do so. The water should be changed frequently, allowing the animal to continue to use the water area as a form of lizard litter box. In their wild environment, the Nile monitor relies on its water source as a means of protection, and as a source of food. It remains important to the animal's captive life to provide it with an appropriate water source. When young Nile monitors can be quite arboreal, but as they reach adulthood and obtain a larger size they become more aquatic. Providing the Nile monitor with branches for climbing opportunities as well as numerous places to bask at varying temperatures will further lead to a healthier and happier reptile.There are a number of substrates available to provide a floor covering. Repti-bark, and other similar specialty substrates are great. Not only do they provide attractive, naturalistic flooring, they also aid in odor control by absorbing liquid waste and some of the smells associated with them. Choosing an appropriate substrate also allows one to better control the humidity in the monitors habitat by retaining more moisture. Make sure that the substrate you purchase is acceptable bedding for reptiles, as certain pine and cedar substrates have proven to be fatal.As adults, Nile monitors will require spacious accommodations, while young Nile monitors are easily housed in readily available terrariums or Reptariums. The Reptarium by Apogee, is ideal for Nile monitors ranging from hatchling to juvenile. Instead of a glass or plastic construction, they are constructed from a very durable nylon mesh, which provides maximum air circulation to your Nile monitor, which helps to control odors. It also allows a more personal interaction with your monitor allowing him to become more accustomed to you. Your monitor being accustomed to positive interaction with you will allow you to have optimal conditions for a more docile animal. The habitat should be spot cleaned anytime that significant soiling is visible. The entire habitat should be cleaned thoroughly at least every two weeks. Any habitat furniture (i.e. branches, rocks, etc.) should be thoroughly washed and scrubbed with a bristle brush.It is important bear in mind the animal's natural behaviors when constructing the habitat for your monitor. In the wild Nile monitors are very effective predators. They often capture their prey by digging. Termite nests are easily ripped open by Nile monitors. As with other monitor species, Nile monitors also possess digging instincts. You will probably notice an evolution of interior decorating, as your monitor digs around and re-arranges items in its habitat. Within their natural habits the nose is often used as a sensory mechanism, by routing around much like a pig. This mechanism is seen most often in captivity when a monitor is exploring the outer edges of its habitat. Due to this rubbing precautions may need to be taken in preparation of the habitat. Using metal screen cages can cause significant damage to the nose as it is rubbed on the metal, thus promoting infection. Even in glass aquariums, rubbing can cause injury to the monitor if the keeper does not keep a close eye on the monitor's habits. Some keepers have found that putting up a visible barrier along the lower portion of the glass deters the rubbing behavior. As the monitor grows in both size and in strength, glass may prove to be more problematic. The Nile monitor has a powerful tail, which becomes a defensive weapon being used like a whip. Nile monitors also have a tendency of being nervous, thus glass breakage could certainly become a concern with larger specimens. When choosing an enclosure for your pet, it is certainly easier to spend a little extra money for a larger enclosure that will house your pet for a longer period of time. This is much easier than buying a completely new habitat every time you're pet grows a little.Along with branches to climb on, providing artificial vegetation also provides a more realistic environment. Artificial plants also have the benefit of ease in cleaning. Not only are they easily cleaned, but they can also be replaced rather cheaply. Another addition that allows normal behavior in your monitor, and every habitat housing a monitor should include, is a hide. This can be one or any number of places for the monitor to hide itself in, thereby feeling safer. Numerous hides are available including half logs, bark sheets, and other natural materials.Temperature / Lighting Requirements:There are a number of ways to achieve the desired temperature inside of your Nile monitors habitat. Keep in mind that unlike mammals, reptiles are cold-blooded, so there health and safety depends on you to make sure that its environment is optimal. The desired temperature range for a Nile monitor, is not that much different from other monitors in the Varanid family. A gradient temperature is preferred, thus allowing your monitor to adjust its own temperature to what it feels is necessary. Many times however this gradient temperature is hard to maintain. An ambient temperature of 80-85 degrees, with a basking spot of 90-92 degrees seems to be optimal for most species and sub-species of Varanus niloticus. At night temperatures may be allowed to drop to 68 degrees. Achieving these temperatures may be accomplished through any combination of ceramic heaters, full spectrum lamps, and under-tank heat mats. Heat Rocks should not be used, as they do not provide a naturalistic means of temperature regulation and can cause injury to your monitor. If necessary to keep at ideal temperatures, ceramic heaters are the best choice for night cycles. Black lights, which are frequently sold for other species, should be avoided as well, as studies suggest injury to the monitor's optical system.For optimal lizard health, the Nile monitor should have simulated day/ night cycles, with the day cycle lasting approximately 14 hours. The lighting should be both UVA and UVB. It is not entirely known how the monitor utilizes these light rays, but it plays a definitive part in the overall health of the lizard including a role in metabolism.Feeding & Nutrition:The Nile Monitor is one of nature's perfect predators. In the wild the Nile monitor is opportunistic and feeds on a varied diet of insects, mollusk, fish, small birds and mammals, and even raids the nest of the Nile crocodile and consumes the eggs. The Nile monitor is also known for trying to eat anything it feels it may overpower. With such a varied diet in the wild, it remains pertinent in captivity to try to simulate a variety diet so that a proper nutritional balance may be obtained. This may also require the occasional supplement to be added, should a natural source for that mineral not be available. Upon hatching, Nile monitors are insectivorous and should readily consume most available feeder insect including crickets, meal worms, super worms, wax worms, and roaches. As they grow larger, various foods should be offered which may include feeder fish, pinkies and feeder mice, and feeder chicks and adults may consume rats. Many keepers have found that their monitor is fond of raw ground turkey, or any of the available pre-packaged monitor diets.One concern in monitor diet is the need of a calcium supplement. Especially as they are growing, your monitor will need a steady supply of calcium, in order to keep up with the developing of its skeletal system. Calcium supplements may be given once to twice per week, but should not be given any more than that. Overdose of calcium can cause calcification to the internal organs of the monitor, thereby killing them. Crickets, in general, have higher calcium content than do most worms. It is up to the owner to find a good balance between proper nutrition and over feeding. As do many wild animals kept in captivity, Nile monitors have a tendency toward obesity. If ignored, this may lead to premature death due to liver damage. If in doubt, always consult with a qualified veterinarian, who may assist you in dietary matters.Handling Your Monitor:The key to successfully raising a Nile monitor is to better understand the animal. In the wild the Nile monitor must quickly develop a strategy for survival in a harsh world. For this reason, hatchling monitors exhibit the same anti-social behavior as there larger counterparts do. Upon hatching the Nile monitor will hiss, inflate its body, whip its tail, and if all else fails, bite hard and hold on. Some monitors are more prone to aggressive behavior than others, but with gentle handling it may be possible to help take the edge off of your monitors personality. With familiarization with you, your monitor should settle down a little bit. This may take days, months, or even years to accomplish, if at all.When you first receive your Nile monitor, give it at least 1 week to acclimate to its new home, before extensive handling. This will help to reduce the stress that your pet suffers. Provide fresh water, but allow time for your animal to acclimate before feeding. When you attempt to handle your monitor, do not grab it in your hand, but rather gently pet it on the sides of its body and sides of its neck. The gentler you are the better the results. As a defensive measure, your monitor may hiss or tail whip. A certain amount of this is going to happen regardless, but remember that anytime your animal is displaying these traits that it is stressed. Avoid fast or jerky movements, and move slowly, deliberately, and calmly around your monitor. Unlike snakes, which do not have ears, monitors have relatively good hearing. Avoiding loud noises while you are handling your monitor is a good idea. Through time, your pet will become more accustomed to you, and you should be able to enjoy a better experience with your animal. Taking the time to better learn about monitors and their habits, or reptiles in general will also give the keeper a better understanding of the monitor's behavior.As with any wild animal, Nile monitors require a certain degree of specialized care and an understanding keeper. Nile monitors grow to be quite large, and very powerful. They can run extremely fast, swim exceptionally, and take down fairly large animals in comparison to their size. Responsibility means never leaving your monitor unattended with children, other pets, or persons who are not familiar with their care. Even the most docile animal can revert back to its natural instinct, which is that of a predator. Nile monitors have a powerful bite, and should not be underestimated. However, with caution and self-education keeping a Nile monitor can be very gratifying and rewarding. The responsible keeper always makes his decisions for the best interest of the monitor.As with any animal, having a veterinarian who is familiar with the animal and does not mind taking the time to establish a good patient-doctor relationship is important. Having a DVM who specializes in herpafauna medicine is ideal, however any DVM who is willing to learn, and take the time necessary for you is certainly advantageous.Reptile City and Varanid Conservation:Reptile City is constantly improving its conservation efforts. We remain at the forefront of conservation efforts and share willingness for better legislation through proper education. We also represent the latest scientific education programs focused on conservation, as well as other research related endeavors with herpefauna.