12 Incredible Monitor Lizard Facts

Monitor Lizard Facts - Megalania
Erik Laan/Shutterstock.com

Written by Cindy Rasmussen

Updated: May 6, 2022

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Monitor lizards are large, scaly lizards with long snake-like tongues. They can grow to be as long as 10 feet long and have large claws and a powerful tail. The Komodo dragon, the world’s largest lizard is one species of monitor lizards, so is the more common Asian water monitor. Let’s take at 12 of the most incredible monitor lizard facts:

1. Choose your weapon: sharp teeth, large claws or poisonous venom?

Apex predator: Komodo dragon

The Komodo Dragon is a large species of lizard that is only found on a handful of islands in the Indonesian archipelago. In order to catch large animals, Komodo Dragons can sit for hours hidden in the vegetation and are well camouflaged by their grey-brown skin as they wait for prey to pass by. The Komodo Dragon then ambushes its victim with incredible speed and force.

Monitor lizards are carnivores and are known to be aggressive attackers of their prey. A typical dinner time ritual would be for a monitor to hide and wait for a passing deer. The Timor deer is a species of deer that a Komodo dragon might catch. The monitor attacks the deer with its large claws and sharp teeth (up to 60 of them!), delivering a venomous bite. The toxins in the venom cause the deer to bleed out and the monitor lizard has dinner. Small animals are swallowed whole while larger animals are ripped into smaller edible pieces.

2. Monitor lizards would win most eating contests!

On your mark, get set, go! Monitor lizards are very fast eaters, consuming large amounts of food in a short period of time. The Komodo dragon has been observed eating 5 ½ pounds of meat in one minute! That is like eating 22 Quarter Pounders (with or without cheese!). They often feast on carrion (dead animals) and can consume almost their total body weight in one sitting!

3. “Don’t bite off more than you can chew.” is not a monitor lizard saying.

Dumbest Animals in the World: Komodo Dragon

A Komodo dragon wolfing down dinner

Monitor lizards swallow most of their prey whole. They have a unique feature in their throat that allows the jawbone to dislocate making their throat bigger! I guess if you need to eat 5lbs/minute this would be a helpful feature.

4. Could monitor lizards compete in a triathlon?

They would do quite well at the running and swimming, but probably are not equipped for biking. Monitor lizards can run fast, with the largest, the Komodo dragon, clocking 12mph. They are fast swimmers too! The Asian water monitor is one of the fastest monitor lizards in the water, using its large tail as a rudder. Maybe they could do a relay with the Komodo dragon running, the Asian water monitor swimming and “Norman the bike-riding dog” could finish with the biking.

5. Nile monitors tag team to hunt.

Nile monitor

A Nile monitor lizard

Another team sport might be hunting. The Nile monitor lizards team up to hunt. If they find a crocodile nest of eggs, with a very protective mother crocodile, one Nile will distract the mother, drawing her away from the nest, while the other Nile steals the eggs. Now that is teamwork!

6. Komodo dragons don’t always get along, sometimes they eat one another.

Two Komodo Dragons (Varanus Komodoensis) do battle

Young Komodo dragons are sometimes eaten by larger aggressive adult Komodos. The young Komodos frequently hide in trees keeping them out of harm’s way, but occasionally an adult will catch and eat one.

7. A different “Meg”, not a Megladon but a Megalania.

Monitor Lizard Facts - Megalania

A statue of how big Megalania would have been. These huge monitor lizards measured 23 feet in length!

The 23 foot long Megalania was an early monitor lizard that lived in Australia. This giant beast is extinct now but was thought to live during the Pleistocene era at the same time as some of the early humans. Fossils of these lizards have been found, but they have not been fully intact. Scientists try their best to piece together the history of these early lizards.

8. One extremely rare monitor lizard looks like a dragon.

Monitor Lizard Facts - Borneo earless monitor

A Borneo earless monitor

The Borneo earless monitor is a long skinny brown lizard without ear openings. Their small front legs are set back a bit and they almost seem to be smirking. They may seem fierce but at 16 inches long they are not nearly as threatening as the 10 foot long Komodo dragon. Because they are so rare there is limited information about their species, this also makes them susceptible to being captured and illegally traded.

9. “I’d like an Icee and a roller dog.” A water monitor was videotaped INSIDE a 7-Eleven!

In Nakhon Pathom, Thailand, a 6-foot long water monitor lizard was videotaped climbing the shelves inside a 7-Eleven convenient store. The reporter said it climbed up to a top shelf and stayed there for over an hour! In many areas of Thailand it is common to see water monitors, however they rarely make human contact.

10. Monitor lizards can be kept as pets.

Monitor lizard facts - black throat monitor lizard on a leash

A pet black-throated monitor lizard getting ready for a walk

The most common monitor lizard to keep as a pet is the Ackie monitor which is one of the smaller lizard breeds. They grow to be around 16-18 inches and weigh around 5-12 pounds. Monitor lizards need a large enclosure that replicates their natural surroundings. For the Ackie monitor you would want an enclosure that is at least 4ft x 2ft x 2ft. Stock your fridge with mealworms, crickets and roaches to feed your lizard. Make sure you can commit to taking care of them for their lifespan of 15-20 years.

11. The oldest Komodo dragon in captivity was 30-years-old.

At the Calgary Zoo in Canada, the Komodo dragon, Loka, died when she was 30-years-old. The lifespan of Komodo dragons in the wild is 20-30 years. The average range for monitor’s life span is from 8-30 years depending on factors like their size, captivity status and diet.

12. King Cobra vs. Monitor Lizard.

Monitor lizard vs cobra

In the battle of

king cobra

vs. monitor lizard the result was a draw

In India, a forest official videotaped a fight between a King Cobra and a monitor lizard. The National Zoo thought that perhaps the cobra mistook the lizard’s tail as a smaller snake because cobra’s usually prey on other snakes. So who won? The report said that both animals were seen leaving the scene and that neither one was fatally injured. It is a draw this time but who knows next time!

There you have it, 12 incredible monitor lizards facts! If you’re looking for more monitor lizard reading, make sure to check out ‘What Do Monitor Lizards Eat? 11 Foods in Their Diet.’

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About the Author

I'm a Wildlife Conservation Author and Journalist, raising awareness about conservation by teaching others about the amazing animals we share the planet with. I graduated from the University of Minnesota-Morris with a degree in Elementary Education and I am a former teacher. When I am not writing I love going to my kids' soccer games, watching movies, taking on DIY projects and running with our giant Labradoodle "Tango".

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