The Asian Water Monitor lizard is a large species of lizard native to South and South East Asia. It can be found over a large geographical range and is one of the most common monitors in the region.
The Asian Water Monitor lizard was first described in 1768 and is often referred to as the Asian Monitor, Water Monitor and the Common Water Monitor, among other names.
Asian Water Monitor Lizard Taxonomy
The Asian Water Monitor Lizard belongs to the Varanus genus of lizards. This essentially means that they are a monitor species. The scientific name for this monitor is Varanus salvator.
There are almost 90 different living species of Monitor lizards with many more extinct. Some other lizards that fall into this category include the Komodo Dragon, Kimberly Rock Monitor and the Nile Monitor.
Some of the other commonly known species of monitor lizards include the Black Throat Monitor and the Mangrove Monitor.
The Water Monitor belongs to a sub-family of monitors called Soterosaurus. Other lizards in this group, such as the Palawan Water Monitor and the Yellow-Headed Water Monitor were once considered sub-species of the Asian Water Monitor Lizard but recent studies have indicated that they are different species.
Asian Water Monitor Lizard Description
The Asian Water Monitor lizard is one of the largest species of lizard in the world. They have a muscular body and a long, powerful, laterally compressed tails which they use for swimming.
Water monitors have a very distinct appearance. They are usually dark brown or black in colour with yellow spots dotted around their body. These spots generally fade with age. Another defining characteristic of these monitors is a black band that usually extends from their eye.
They have a typical monitor-like appearance, with a long neck, elongated snout, serrated teeth and sharp claws.
Asian Water Monitor Size
An Asian Water Monitors size depends on many factors including gender, diet and locality. These lizards can grow to between 4.5ft and 6.5ft. The male of this species will usually grow larger than a female.
The largest specimen ever recorded measured over 10ft in length. This was an exceptional specimen and most Asian Water Monitor lizards won’t grow anywhere near this length. A fully grown adult can weight almost 20kg.
Geographical Range and Habitat
The Asian Water Monitor lizard has a very large distribution. The can be found in India, Bangladesh, Sri Lanka, Myanmar, Thailand, Cambodia, Laos, Vietnam, and parts of South China. They can also be found on the islands of Malaysia, Singapore and the Indonesian islands of Sumatra, Java, Bali, Borneo, and Sulawesi.
Parts of their range is shared with other species such as the Burmese Python, the Timor Python, the Dumeril’s Monitor and the Borneo Short Tailed Python.
Their preferred habitat consists of forested areas, wetlands and mangrove swamps. However, they have adapted to thrive in a wide variety of other habitats. They have adapted well to human habitation and can be found on agricultural land and even in cities with canal systems.
This Monitor is known to live everywhere from desert regions to areas that receive snowfall in the colder months but their preferred habitat consists of wetter regions with a constant air temperature of around 24C.
They are usually found close to water and are excellent swimmers using their tail as a fin to propel them through the water. They are also excellent climbers and can be found resting in trees. Juveniles are semi-arboreal while adults will spend most of their time on the ground or in water.
Asian Water Monitor Lizard Diet
The diet of an Asian Water Monitor lizard is strictly carnivorous. They are not a picky eater and will consume almost anything that is smaller than them. They are even known to be scavengers, picking the meat off dead carcasses.
They will eat anything such as fish, frogs, rodents, birds, crabs, snakes and mammals. These lizards have an excellent sense of smell and can pick up the scent of a carcass from a great distance away. They have a forked tongue that they use to pick up the scent particles of their prey.
Are they Venomous?
There is a long-standing debate as to whether these lizards contain venom. The two sides of the argument are that they are not venomous, but they have bacteria in their saliva that helps to break down food. While the other side debates that they do in fact produce venom. More research is needed in this area.
It was once believed that the effects of a monitor bite were due to bacteria in their saliva but recent research is indicating that they may actually contain a mild venom, at least in some species.
It is believed that this venom/bacteria may be used as a defensive mechanism to fend off predators, to help digest food or even to capture and kill its prey.
Asian Water Monitor Lizard Breeding
An Asian Water Monitor Lizard is a prolific breeder in the wild and females can produce two or more clutches a year if the conditions are correct. The gestation period for the eggs are around 30-45 days.
The size of a clutch size can vary greatly with most females laying between 10-20 eggs. This is highly variable and depends on many factors including the female’s size, age, diet and whether she has already laid in the season.