Facts on Pet Monitor Lizards

Monitors (family Varanidae) are small to large lizards, with engaging personalities and often striking looks. Native to Australia, Africa and Asia, monitor lizards are popular pets among lizard enthusiasts. Sometimes this owner-pet relationship is mutually rewarding, and other times it is frustrating for the keeper, and miserable for the lizard. The difference between the two extremes lies largely in the choice of species.

  1. Some Species Become Very Large

    • Monitor lizards differ in size greatly throughout the clade, and the largest species are at least 10 times the length of the smallest species. Prospective owners should be very careful to select from the smaller end of the spectrum to give themselves the best chance of success. Emerald tree monitors (Varanus prasinus) and spiny tailed monitors (Varanus acanthurus) are two popular species that only attain 2 to 3 feet in length. White-throated monitors (Varanus albigularis), water monitors (Varanus salvador) and Nile monitors (Varanus niloticus) are a few species that are frequently available, yet reach sizes that are inappropriate for many hobbyists, unless they have the space and experience necessary for caring for such a large lizard.

    Personalities Differ

    • Monitors are undoubtedly intelligent by reptile standards, and data from a 2008 University of Tennessee study suggests that monitors can count to at least six. Monitors of some species have complex social interactions, and can recognize their keepers. Given this, it is no surprise that monitor lizards have different personalities from species to species, and to a lesser extent, individual to individual. While there are always exceptions, white-throated monitors, savannah monitors (Varanus exanthematicus), spiny-tailed monitors, and water monitors are the most tractable species. Conversely, species like the Nile monitor are noteworthy for being very difficult to tame, regardless of the time invested. Do not underestimate the damage an angry, 6-foot-long monitor lizard can inflict.

    Monitors Require Spacious Enclosures

    • Monitor lizards are active reptiles that require large cages. In fact, some of the largest monitors have natural ranges in excess of 2,000 acres. In captivity, monitor lizards should be provided with two to three times their body length of cage length, and one and one-half times their body length in depth, as an absolute minimum. Scaled for a 6-foot monitor lizard, the enclosure would be the size of a small room, at a minimum, 12 feet by 9 feet. Most keepers don't realistically have this space to offer, and should opt for a very small species. Bear in mind that a lizard only 2 feet in length would still require a 4- to 6-foot-long enclosure, which is bigger than many keepers have room or the budget for.

    Monitors are Hungry Lizards

    • Monitor lizards of all species are almost exclusively carnivores. Though the Gray's monitor (Varanus olivaceus) does eat fruit, it isn't a species readily available in captivity. Small and juvenile species require daily feedings of insects like crickets, roaches and mealworms. You can occasionally offer rodents or ground turkey as well to accelerate their growth. Adult monitors are best maintained on a rodent-based diet, and though they can be fed less frequently than young animals, large animals will still require five or more large rats per week. The costs of such a diet become significant very quickly, and are often overlooked by new keepers.