Say G'Day to the Goanna!
The lace monitor is also known as the goanna. This species is the second largest species of lizard found in Australia with some individuals reaching lengths of up to 2m (6.6ft).
These animals are skilled climbers and are often seen resting high in trees. They are carnivores which hunt a number of mammals and birds.
Appearance
What does a Lace Monitor look like?
Most of the lace monitor’s body is covered with blue grey scales on the top with cream underneath. Two colour phases of the lace monitor are recognized. One known as the bell's phase monitor has large bands of cream running across the body while the other has a randomized pattern of cream patches and spots across the body.
Their tail is blue grey and ringed with cream bands which begin narrow and expand towards to the base of the tail. It makes up around half of their length.
The tongue is forked like that of a snake. Their toes have long claws which they use to climb.
Adult lace monitors measure between 1.5 and 2m (5 and 6.6ft). On average, they weigh 20kg (44lbs).
Adaptations
How does the Lace Monitor survive in its habitat?
Lace monitors have a forked tongue. With this branching out on either end they can determine the direction from which a smell is coming. When hunting they will continuously flick the tongue allowing them to identify potential prey items.
The claws of the lace monitor are large and allow them to cling to the branches of trees as they climb them.
Diet
What does a Lace Monitor eat?
The lace monitor is a carnivore. Their diet includes insects, reptiles, mammals, birds and their eggs. Introduced prey items have become part of their diet such as rabbits which in one study were found to be part of the diet of 32% of the individuals studied. A study conducted in an area with few introduced species found the primary prey items were possums and gliding marusipals which can be easily captured as they rest in trees during they day.
They are also opportunistic feeders eating carrion when they come across it. Both studies referenced above found carrion to be a major component of the diet with macropods such as wallabies and kangaroos being common prey items. At times they will scavenge through bins in picnic areas.
They can gorge themselves when feeding on a large kill and then do not need food for the next few weeks.
These animals are active predators and spend their day searching for food.
Range
Where do you the find the Lace Monitor?
Australia is the native home of the lace monitor. Here they can be found throughout Queensland, New South Wales, Victoria, South Australia and the Australia Capital Territory.
Habitat
Where can a Lace Monitor survive?
They make their home amongst open and closed forest as well as the coastal tablelands. For shelter they use tree hollows, termite mounds, a hole among rocks and logs.
Reptile News Stories
Reproduction
How does a Lace Monitor produce its young?
Breeding begins during October with egg laying peaking during December and January. Males will battle for the rights to mate with a female. They will hold the opponent with their front claws and rise on the hind legs. By using an inflated throat pouch they will intimidate each other till one admits defeat.
Following a successful mating it will take 4-6 weeks for the female to be ready to lay her eggs. They will find a termite mound in which to lay between 4 and 14 eggs. The termites will then reseal the nest. The inside environment of the termite nest remains at a constant temperature which is suited to the incubation of the eggs. Where a termite mound is not available the eggs are deposited in a mound of vegetation and as this decomposes heat is generated to incubate the eggs.
The eggs incubate for between 8 and 9 months at which point the female returns to the termite mound where they will dig out the hatchlings.
It will take between 4 and 5 years for the lace monitors to reach sexual maturity.
Behaviour
What does the Lace Monitor do during its day?
These animals are active during warmer weather. One study found the species was able to be active when air temperatures were as low as 16oC by angling their body to the sun. This allowed them to heat their body to a temperature of 38oC. When it cools, they take shelter in a tree hollow or beneath a fallen tree or rock.
Because of their strong claws they are able to climb trees which they can use as a means of escaping predators. Lace monitors are also competent swimmers.
The lace monitor is solitary only coming together with other lizards to mate.
Each individual lace monitor makes use of a large range. These often overlap the range of other lace monitors and it does not appear that individuals defend their territory against entry by other monitors.
Predators and Threats
What stops the Lace Monitor from surviving and thriving?
Predators of the lace monitor include dingoes and birds of prey. Lace monitors have been observed to consume the eggs of other lace monitors from termite mounds. Introduced predators such as the red fox and cat have significant overlap in preferred prey items and would compete with the lace monitor for prey.
One form of defence is a mild venom which is present in their saliva.
Quick facts
Lace monitors are also referred to as ‘goannas' and is often referenced as the tree goanna due to their regular habit of tree climbing. Goanna is taken from a name given to them be early settlers who believed this species was related to the iguanas.
It is Australia’s second largest monitor after the perentie. These lizards are related to the Komodo Dragon of Indonesia which is the largest species of monitor lizard alive today.
The scientific name of the lace monitor, Varanus varius, roughly translates as ''many-colored lizard.''
References
Venz, M., Wilson, S., Hobson, R. & Sanderson, C. 2018. Varanus varius. The IUCN Red List of Threatened Species 2018: e.T83779090A101752385. https://dx.doi.org/10.2305/IUCN.UK.2018-2.RLTS.T83779090A101752385.en. Downloaded on 26 April 2020.
“Lace monitor (Varanus varius)” (no date). Berri: Natural Resources Centre.
Jessop, Tim & Urlus, Jake & Lockwood, Tim & Gillespie, Graeme. (2010). Preying Possum: Assessment of the Diet of Lace Monitors (Varanus varius) from Coastal Forests in Southeastern Victoria. Biawak. 4. 59-63.
Weavers, B. (1989) “Diet of the Lace Monitor Lizard (Varanus vadus) in south-eastern Australia .” Sydney: The Royal Zoological Society of NSW.
Carter, B. (1992) “REPRODUCTIVE ECOLOGY OF THE LACE MONITOR VARANUS VARIUS IN SOUTH-EASTERN AUSTRALIA.” Canberra: Australian National University.
Australian native Wildlife Park Townsville (2018) Billabong Sanctuary. Available at: https://www.billabongsanctuary.com.au/lace-monitor/ (Accessed: March 2, 2023).
Lace Monitor (2021) Backyard Buddies. Available at: https://backyardbuddies.org.au/backyard-buddies/lace-monitor/ (Accessed: March 2, 2023).
Love Reptiles? Meet more in our fact files below.
Copyright The Animal Facts 2023
