Heath Goanna
Scientific Name
Varanus rosenbergi
Conservation Status
Least Concern (IUCN red list of threatened species). Listed as Vulnerable in South Australia and listed as Endangered in 5 natural resources regions.
This animal cannot visit your location for a presentation.
This animal is not used for Wilbur’s Wildlife event displays.
This animal is on show during private zoo tours.
Our Animals
Wilbur’s Wildlife is home to a 1 year old heath goanna known as Penelope. Penelope wasn’t held much when she was young and as such is not much of a people goanna. Instead she prefers to be at home under the heat light in her 2 story enclosure for people to view on their tours.
Appearance
Heath goannas are a slate grey colour with bands of yellow, orange or cream spots running down the body. The long slender tail is banded with yellow or cream. The tip of their tail is the same slate grey colour as their body. Juvenile animals have bolder orange marking’s which fade as they grow. They have a white belly. A black stripe runs out from the eye and down the neck.
The average heath goanna measure’s 1200mm long with a maximum length up to 1500mm long. Male Rosenberg’s monitor’s weigh up to 1.9kg. This may be up to double the weight of the female.
Lifespan
There is currently insufficient information to prove the upper lifespan of the heath goanna. One study on Kangaroo Island has animal’s being studied which have reached 30 years’ old.
Diet
The heath goanna is a carnivorous species which feeds on a range of frogs, birds, lizards, eggs, insects, mammals. They will also eat carrion.
Habitat
Heath goanna are found across Western Australia, South Australia, New South Wales, the Australian Capital Territory and Victoria.
They have the southernmost range of any Australian monitor and are the most tolerant of cold of any monitor in Australia.
Habitats occupied by the heath goanna include woodland, heath, sclerophyll forest and temperate forest. They prefer areas with sandy soil.They use burrows to hide and rest. These may be hollow logs, rock crevices or a burrow which has been made by themselves or another monitor.
Their home range can be anywhere from 80 to 1000 hectares in size.
Reproduction
Heath goannas will typically begin their mating period around the longest day of the year. Mating take’s place over the next four to six weeks.The female will lay up to 14 eggs. These are deposited in a termite mound during summer. It may take up to 2 days for the female to excavate a suitable chamber in the termite mound in which to deposit her eggs. Once the female lay’s her eggs termites will quickly begin to repair the damage which seals the eggs inside.
Over autumn and winter these eggs are maintained at a constant temperature and humidity inside the termite mound. They will hatch in the spring.
Following hatching the juvenile heath goannas dig themselves out of the mound. In some instances, the mother may also return to dig the hatchling’s out of the termite mound. They will return to the mound to feed on the termite’s it houses for the first few days of their life.
Only one in twelve hatchlings’ will survive to one year of age.
Sexual maturity is reached at 9 years’ old.
Behaviour
Rosenberg’s monitors are solitary animal’s only coming together for breeding season.
They are active by day. Their dark colouration assist’s with warming up in the colder region’s where they live.
Threats
Natural predators of the heath goanna include birds and snakes. Juvenile heath goanna may be preyed upon by adult monitor’s.
Introduced predators such as cats, dogs and foxes eat heath goanna.
Their habitat is being destroyed including termite mounds being removed which leaves them without a suitable place to lay eggs. Their habitat is also increasingly fragmented which leaves these animals at risk as they need large areas to find food.
Rosenberg’s monitors are regular road kill victims. As more roads in their habitat are sealed and speed limits increased the rate at which these animal’s die increase’s.
How you can help
You can protect remnant vegetation and termite mounds on your land. You can also leave fallen logs in the bush as these provide valuable habitat for these animal’s.
To prevent them being killed by cats or dogs you can keep these animal’s inside.
Discovery Circle are studying the heath goanna and appreciate reports of any sighting of monitor’s in South Australia. These can be reported at https://www.discoverycircle.org.au/projects/goanna-watch/.
Quick Facts
The heath goanna is also known as the heath monitor, Rosenberg’s goanna, Rosenberg’s or heath goanna.
References
Bennett, D. and Sweet, S. (2010). Varanus rosenbergi (Heath Monitor, Southern Heath Monitor). [online] Iucnredlist.org. Available at: http://www.iucnredlist.org/details/178031/0 [Accessed 13 Feb. 2018].
Department of Environment, Water and Natural Resources. (2015). Help Save the Heath Goanna. [Brochure]. Retrieved from https://www.discoverycircle.org.au/wp-content/uploads/2015/09/AMLR-Goanna-Factsheet.pdfNSW Government, Office of Environment and Heritage (2017, September 5th). Rosenberg’s Goanna – profile. [Online], Retrieved from http://www.environment.nsw.gov.au/threatenedspeciesapp/profile.aspx?id=10826
Pelican Lagoon Research & Wildlife Centre. Rosenberg Goanna. [Online]. Retrieved from http://www.echidna.edu.au/rosenberg_goanna/rosenberg_goanna.html
Swanson, S. (2014). Field Guide to Australian Reptiles. New South Wales. Pascal Press.
Smith, James. (2016). Wildlife of Greater Adelaide. Stepney. Axiom Publishers.
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