Monitor Lizards as Pets

Recent studies have revealed that Monitor lizards are perhaps the most advanced and intelligent of all lizards. While many Monitor lizards are too large for the average household, moderately-sized and dwarf species make fascinating pets. However, as even the smallest Monitor can inflict serious injuries with their sharp teeth and powerful jaws, they are suitable only for well-experienced adults with the space and time required for their upkeep.


The world’s 73 Monitor species are classified in the family Varanidae and the genus Varanus. Five new species, one reaching over 6 feet in length, have been described since 2010.

Range and Habitat

Monitors are found Asia, Africa and Australia. They reach their greatest diversity in Australia, where Lace Monitors (V. varius) and other giants fill roles held by large carnivorous mammals on other continents. Nile Monitors (Varanus niloticus), are established in south Florida, USA, and are a major environmental concern there. While most Monitors dwell in tropical regions, the Desert Monitor (V. griseus) weathers the harsh winters of Kazakhstan (think Vermont, USA).

Monitors occupy rainforests, swamps, grasslands, riverside thickets, deserts, village outskirts, rocky savannas and many other environments. Highly-aquatic, burrowing and treetop-dwelling species are known.

Monitors actively forage for food, and take prey as diverse as termites, deer, wallabies, snails, snakes, turtle and crocodile eggs, carrion, human garbage, barnyard fowl, other lizards, fish and an unending assortment of other foods. The recently- discovered Sierra Madre Forest Monitor (V. bitatawa) and the Philippine Monitor (V. olivaceus) are unique in consuming fruit, while the Komodo Dragon occasionally attacks and kills people. In 2005, it was discovered that several Monitors, including the Komodo Dragon, produce venom that affects their prey’s blood pressure and clotting ability.

Appearance and Temperament

All Monitors have muscular bodies and powerful limbs. They range in size from the 8 inch-long Short-Tailed Monitor (V. brevicauda) to the Komodo Dragon (V. komodoensis), the world’s largest lizard, which occasionally tops 10 feet in length. A number of those popular in the pet trade measure 3-4 feet in length.

Monitors are extremely alert and easily startled. Individuals vary greatly in personality, with some becoming docile while others remaining aggressive despite years of captive life. All Monitors can inflict severe bites and scratches, and are likely to snap at nearby movements when they are hungry…which they always are! Water Monitors (V. salvator), and other large species are not suitable for most private collections.

Monitor Lizard Housing

Storr’s Monitors (V. storri) and other small species may be housed in 55 gallon aquariums, while those in the 3-4 foot range are best kept in homemade enclosures measuring at least 4x4x4 feet. The 5-foot-long Savannah Monitors (V.exanthematicus) need correspondingly larger quarters; the giants - Nile, Lace, Crocodile and Water Monitors - require room-sized enclosures with drainable pools.

Monitor Lizard Diet

Green Tree Monitors and other small species need a highly-varied diet comprised of roaches, crickets, butterworms and other invertebrates, along with pink or fuzzy mice. Larger species, such as the Nile Monitor, fare well on mice, rats, and whole freshwater fishes.