Australian Dwarf Monitor Hatchling Husbandry

A healthy hatchling dwarf monitor lizard should be virtually indestructible. When proper housing, dietary, and social requirements are met, all of the historically common problems keepers experience with hatchling varanids can be avoided. To ensure the health and future reproductive viability of our hatchling monitors, several guidelines and practices are followed and implemented here at Reptile Revolt.

Enclosure & Temperature
Hatchling monitor lizards will thrive in a relatively simple enclosure. For hatchlings, we suggest keeping it simple for the first 3-6 months. A standard twenty gallon glass aquarium seems to work well as does most medium sized Exo Terra or ZooMed enclosures. The lids on these are fine wire mesh so there shouldn’t be an issue of escaped animals or prey items. If opting for the aquarium route (not as advised but they can work) then you need to devise a way to tighly secure a top that allows for ventilation while also maintaining sufficient temperature. Whichever route you choose to go with, ensure that the lid is equipped with a light fixture which holds a standard 30-50watt flood light over the basking area as well as a UV light for your animal. You can achieve this by using the basic “reptile dome light” (which can also be bought at Home Depot for half the price as a pet store) or if handy, you can wire your own fixture. Perhaps it sounds intimidating but I can assure you that it is a very easy thing to do. Lots of online tutorials how to do it. The basking area is located about 6-8 inches from one side of the enclosure. The distance between the bottom of the flood light and the basking surface depends on the wattage of the bulb. What we use for hatchlings is the Philips Ecovantage 39w (50w equivelent) and the bottom of the bulb is approximately 8 inches from the basking surface. This ensures that basking area will reach the desired surface temperature of approximately 110°F - 125°F. Its important to note that this temperature is surface temperature as compared to air temperature. You can determine the surface temperature by using a Temp Gun which can be found at many reptile retail locations or you can find one thats just as useable from HomeDepot or Lowes. Same technology, just not the reptile-specific packaging. Basking area air temperatures are going to be higher than the opposite side of the enclosure for obvious reasons. If you find that the opposite/cooler end of the enclosure ambient air temperature is too high, increase the amount of airflow in the top to allow for more heat to escape. Adjust accordingly until you achieve the desired ambient air temp on both sides. Where you position your enclosure in your home will impact the ambient temperatures within the enclosure. Placing it near a window may result in temps elevating too much during the day and plummeting at night. The same could be said if placed too close to a heat/cool source such as an air conditioner or radiant base board heat. Every effort should be made to find an ideal location of the home that has a room temperature that doesnt fluctuate wildly.

Enclosure furniture can consist of flat pieces of wood or bark placed directly on the substrate. The most common product being virgin cork bark. This provides the hatchlings with a tight, secure place to hide, and search for prey. Many of the enclosure furnishings commonly purchased are more aesthetically pleasing to the keeper rather than useful for the monitor. But, these furnishings can be provided without any detriment to the enclosure inhabitants and should only be considered as decoration vice a needed husbandry item. So, if you want the SpongeBob pineapple hut in the enclosure then I suppose go for it. But, it is not a substitute for proper furnishings such as hides, rocks, branches, etc.

Cypress mulch, Repti Bark, and even plain paper towels are the preferred substrate for hatchlings. It is relatively hygienic, dust free, pleasant smelling, and provides them with many tiny crevices in which they can explore, hide, and use to search for prey. We utilize ReptiBark for our substrate for all dwarf monitors regardless of size. Its easily sourced, has a pleasant aroma, and is mold/mildew resistant. For basking surface, a simple stone such as slate, flagstone, or even a ceramic tile placed a safe distance underneath the basking bulb will do just fine.

Water/Food and Nutrition
Hatchling varanids are ravenous feeders. It is virtually impossible to over feed a healthy, rapidly growing monitor. Every second day, hatchlings are fed a variety of food items. Their diet consists primarily of insect matter (1/2” crickets and dubia), but may be supplemented occasionally with pinky – fuzzy mice, scrambled egg, chicken, turkey, and quail.

When given the option, hatchling monitors will almost always choose large prey items over small prey items (relative to their body and head size). To the disbelief of many keepers, hatchling monitors of the subgenus odatria, can easily consume a very large (2/3” – 3/4”) cricket. They seem to ignore, or simply refuse to eat prey that is too small relative to their body size. Large prey items seem to stimulate a much more aggressive feeding response. Whether it’s due to the size of the target presented, or the faster movements of large prey, there appears to be a definite preference for more robust, live food items. It is also worth mentioning the importance of gutloading your feeders. Insect prey items should be fed a variety of fruits, vegetables and grains on a regular basis. When these insects are consumed, their stomach contents (gutload) are passed onto the monitor. When feeders are fed a variety of nutritious foods, the need for a multivitamin is greatly diminished. Monitors which are housed indoors and have no exposure to natural sunlight should be offered a calcium and vitamin D3 supplement on a consistent basis or ensure that the monitor is exposed to sufficient UV on a regular basis. Choose one or the other but do not provide D3 if an animal already has an appropriate level of exposure to UV as it can lead to a toxic overload of D3 which can/and will be to the animal’s detriment. Many calcium powder products are offered in a D3 version as well as a non-D3 version for animals that receive adequate UV exposure via a bulb or being outdoors. n independent UV bulb with the proper rating (we use Reptisun 10.0). This in an integral part of maintaining optimum health of your dwarf monitor as it promotes the absorbtion of D3 which is the cornerstone of good health and longevity. . Vitamin D3 allows reptiles and other animals to metabolize calcium. UV radiation from the sun is a reptile’s primary source of vitamin D3. In the absence of natural sunlight, vitamin D3 must be supplemented.

Water is offered via a shallow dish. The dish should allow insects to climb out easily. Hatchling enclosures are sprayed lightly every 2-3 days. The substrate and cage furniture should appear dry within 4 - 8 hours after spraying. The frequency of misting will vary based on your local relative humidity that can be achieved in your specific enclosure. Some dry out considerably faster whereas others hold moisture and therefore humidity much easier/longer. If the enclosure remains wet until the next time to spray then reduce the amount of spray during the session or reschedule a new date to re-spray in order to allow the enclosure to dry out again. Failure to do so can and will cause health issues for the monitor. Fungal issues are their limbs is easily achieved when forcing the environment to be overly saturated and as a result insufficient time to adequately dry out. In regions of low relative humidity, keepers might be required to mist the enclosure more often. As a general rule, your enclosure should not appear wet and if it does, be prepared for it to lead to secondary health concerns.

Should hatchling varanids be housed individually, in pairs, or in small groups?
This is one of the most common questions asked pertaining to hatchling monitors. The answer is not simple, and can vary depending on species and the individual personalities of the monitors in question. One of the most common myths surrounding monitor colonies is that their sex is determined within the group and the most dominant animal will most likely turn out to be male. There is little evidence to support this theory and there are several other reasons that would explain the observed sex ratios experienced in captivity. Your odds for a diverse sex ratio increase with the number of animals as it provides you with more chances of a different sex but there isn’t any other increase in odds. That said, in our experience, there has been no significant difference in the sex ratios observed between animals raised individually or in groups. Behaviorally, most dwarf monitors do quite well in groups until they approach sexual maturity. At which point, some manner of dominance or territorial displays become more likely. This is often when hobbyists begin to suspect which animal is a specific sex. This is a particularly important time to observe their behavior closely if housed in groups of 2 or more. Some animals may become more aggressive and dominant over the other resulting in stress. This stress can cause a monitor’s health to crash surprisingly fast. If you witness any aggressive behavior that appears to have one or more animals not keeping pace with the size and health of another then its time to consider separating your group to achieve a more peaceful environment. Ultimately, I recommend keeping them of groups of 1 male to 1 female. The social hierarchy within the enclosure is far easier to manage than any other ratio. It also makes the observation and recognition of a reproduction cycle easier to notice. There is no general rule for grouping animals that will encompass every species within the subgenus Odatria. Through observation, trial and error, several species specific rules have been formulated concerning the optimal number of animals that can be housed together for rearing purposes. The following table summarizes recommendations, but as a general rule, the overall well being of each hatchling is greatly increased when there are fewer animals per enclosure.