Savannah Monitor
- Common Group: MONITORS & TEGUS
- Common Name: Savanna Monitor
- Scientific Name: Varanus exanthematicus
- Distribution: Central S. Africa
- Size: 2.5' - 3'
Natural History
The savannah monitor, as one would expect given the common name, is found in the savannahs and grasslands of central Africa. These animals are superbly adapted predators that hunt and forage during the cooler daylight hours for foods consisting of insects, birds, eggs, rodents, and other reptiles.
This species is very similar in general morphology to the black throated monitor and the white throated monitor. In some places, these three species have overlapping ranges, and were at one time considered the same species. Incidently, all of these monitors have very similar care requirements, and the guidelines provided below may be applied to the maintenance of any one of these animals.
In the past, savannah monitors were imported to the United States and Europe in massive numbers, often resulting in dehydrated, starving animals that failed to thrive. Luckily, with the recent interest in conservation within their countries of origin, these monitors are being "ranched," that is being bred and/or hatched in controlled environments in their native land. As a result, healthy and spunky babies are now widely available, as are animals bred here in the States by a few dedicated hobbyists.
Size and Longevity
In general, savannahs are one of the more reasonably sized monitor lizards, making them a good choice for beginners or those not willing or able to house a truly giant lizard. Hatchlings are only a few inches long, but grow rapidly and can reach maturity in as little as 2 years, though 3 to 4 years is more common.
Adults range in size from 2.5 to 3.5 feet in total length with both larger and smaller specimens occasionally occurring. Savannah monitors have a thick, bulky build, making them seem larger than they actually are.
Properly cared for savannahs can be expected to live well over 10 years, with 15 to 20 years being a reasonable average. Unfortunately many monitors die prematurely as a result of misinformation, poor husbandry, or an inadequate diet. By replicating nature as much as possible, we can ensure that our monitors live long, healthy lives.
Housing
A single or pair of hatchlings can be comfortably kept in a 20 or 30 gallon terrarium or equivalent enclosure for the first few months of life. Once they exceed 8 inches, you should begin shopping for a larger enclosure.
A single adult can be maintained in a 6 foot by 2 foot enclosure, while 6 by 4 would be best for a pair. These animals usually get along in pairs or small groups, but aggression between males or surrounding feeding have been reported. If ample space if provided, as well as an assortment of hiding and basking spots, these animals can be considered communal.
Smaller enclosures for babies and juveniles can be of the all glass terrarium variety with a sliding screen top. Larger animals can be housed in molded plastic enclosures such as those manufactured by Vision Herpetelogical, or in other custom enclosures.
Remember, monitors are smart, active, and powerful animals. Attention should be paid to the size and security of any cage designed to contain a large monitor.
Heating and Lighting
These monitors are found throughout central Africa fairly near to the equator, and as such require high daytime temperatures for proper health. The ambient or background temperature within the cage should range from 80 degrees on the cool side to 90 degrees on the warmer side of the enclosure. A basking spot should be provided to create a single zone (multiple basking spots for multiple animals) that gets around 100 degrees. Larger animals can tolerate higher basking temperatures, and there are many reports of basking spots exceeding 130 degrees being utilized by this species.
At night, temperatures can safely drop to 75 degrees. If needed, heating pads or ceramic heat emitters may be used to increase nighttime temperatures to acceptable levels. During the day, basking bulbs, ceramic heat emitters, or both should be used to ensure high heat and plenty of bright light.
There are differing opinions as to the necessity of full spectrum lighting for monitor lizards. In theory, because they are eating a wide variety of whole prey items, they should be receiving ample amounts of vitamin D3 and calcium. However, captive reptiles rarely receive a diet anywhere near as varied or nutritious as they would receive in the wild. Additionally, wild savannah monitors do bask for extended periods of time in unfiltered sunlight, so it seems only fitting that they should be exposed to similar conditions in captivity.
In larger enclosures, self-ballasted mercury vapor bulbs (such as Zoo Med’s Powersun) can be used as both a heat source and for ultraviolet (UV) light. In smaller enclosures the use of an independent heat source in conjunction with a traditional fluorescent UV bulb is acceptable.
Substrate and Furnishings
Savannah monitors are natural diggers, both when foraging for food and when constructing burrows. A substrate that allows for this behavior is recommended, as is one that will retain enough humidity to offset dehydration and shedding issues. Mulch type bedding such as orchid bark or cypress mulch are ideal, and aspen products (shredded or chipped) have proven successful as well.
As an active species, much of what you put into your monitor enclosure will get pushed around and potentially toppled over. A simplistic set-up consisting of a few chunks of heavy wood, some sort of shelter, and a sturdy basking platform will suffice. Ultimately, trial and error will dictate what does and does not work for your animal.
Live plants should be avoided, as they tend to die in the extreme heat of a savannah monitor enclosure, not to mention the physical trauma they may endure on behalf of a large, curious lizard. Artificial vines and plants may be used to beautify the monitor home, but are not required.
Water and Humidity
Despite hailing from an arid environment, savannah monitors do drink water regularly, and will even soak if given a large enough receptacle. A heavy dish that is unlikely to tip is recommended, as is one that can be easily disinfected if the animal defecates in the water.
In the wild, these lizards spend the hottest parts of the day in the refuge of moist burrows. The humidity levels within these "micro habitats" prevents dehydration and helps to ensure healthy skin shedding. In captivity, little is required as far as maintaining ambient humidity, however, the use of one or more so-called humid-hides is recommended. These are simply standard hide areas (cork bark, half-logs, etc) that have been stuffed with moist soil or barely wet sphagnum moss.
Nutrition
In the wild, savannah monitors are both active hunters and scavengers. Recent studies have shown that the majority of their diet consists of insects (roaches, termites, scorpions, millipedes), birds, eggs, other reptiles, and rodents. The captive diet should be similar, with an emphasis on invertebrate prey.
Young monitors will enjoy a staple diet of appropriately sized mealworms, waxworms, and feeder roaches. Avoid feeding young monitors rodents, as young, unweaned mice are very high in fat, but low in other more valuable nutrients.
Older monitors can receive rodents occasionally as part of a balanced diet. One or two rodents a week should be the absolute maximum. Keep in mind that these animals are simply not designed to digest large quantities of fur and fat, and the constraints of a captive lifestyle can only compound potential issues.
Even adult savannah monitors should be fed lots of insects. A colony of large roaches (such as giant Malagasy hissing roaches) would be a good investment, and if properly maintained, should provide a constant supply of food items for your lizard. Crickets and larger mealworms will also be consumed.
A mixture of ground turkey, raw egg, and a suitable calcium/vitamin supplement has proven very successful in both the private sector and among zoos for maintaining large, carnivorous lizards. As long as careful attention to supplementation and variety, this mixture can make up as much as half of the lizards staple diet.
All food items, with the exception of rodents and pre-mixed diets, should be regualruy dusted with a high quality calcium/vitamin D3 supplement. Food for growing monitors should be dusted several times a week, while less frequent supplementation is acceptable for older lizards. A good multivitamin should also be employed, and as formulas differ, follow the manufacturers directions for dosage information.
It should be noted that savannah monitors are particularly prone to obesity and subsequent medical problems. Poor diet, coupled with lack of room to exercise quickly result in an overweight monitor. Avoid overfeeding, try to replicate the natural diet, and provide ample space to avoid these problems.
Handling
In addition to being hardy, reasonablely sized, and readily available, savannah monitors are also toted as one of the easiest monitor species to tame. With regular, gentle handling, most of these animals will learn to tolerate, or even enjoy, human interaction.
Babies can be nervous and defensive, but this is to be expected of a young, frightened animal. After providing ample time for your pet to settle into it’s new home you can begin the process of creating a pet-owner bond with your lizard.
© LLLReptile & Supply, Inc 2006