Varanus gouldii
Sand Monitor, Gould's Goanna

Gould's goanna is commonly found throughout Australia and New Guinea except on Tasmania and in south-eastern Victoria state. (King and Green, 1993; King, 1980)

These goannas are widely distributed throughout woodland habitats. They are solely a terrestrial species associated with sandy soils. This goanna is more commonly found in the wet season than the dry season. (Delean, 1981; Doles and Card, 1995; King and Green, 1993; Shine, 1986)

Adult female Gould’s goanna average two-thirds the body length and only one-third the mass of adult males. Adult males are approximately 32 cm in length while females are approximately 28 cm. The lizard is greenish-gray with uniform ringed small yellow spots all over its body. The spots are faint towards the neck but are more prominent on the tail and lower torso. The snake-like head is flat with the yellow pattern on the sides. The bottom quarter of the tail is long and solid yellow.

(Shine 1986)

During the wet season when breeding occurs, the male goanna locates the burrow of a female and builds a burrow of his own a few meters away. Over several days the male and female spend an increasing amount of time together. Eventually, they begin to copulate. They continue to mate over and over again for several days. During this period of intense breeding activity, the pair may share the same burrow. After many days the intensity of copulation declines and the goannas separate and forage independently. When it is time to lay the eggs, the female locates an active termite mound. She digs a tunnel towards the center of the mound 50 to 60 cm deep. At the end of the tunnel she digs a large cavity. The female then sits on the top of the mound and lays 10 to 17 eggs into the tunnel. Afterwards she refills the tunnel, and the termites reconstruct the mound around the goanna eggs. The termites regulate the temperature and humidity, so this is an excellent place for development of the eggs. Delayed fertilization has been recorded in this species.

In this diurnal species, males have larger territories and are more active than females. The entrance of a goanna burrow is often beneath a flat rock, a small shrub, or a fallen log. Gould’s goanna often use the warrens of introduced rabbits for shelter instead of constructing their own burrows. The burrows are important for providing protection from predators and weather.

While foraging, goannas' attention is focused on digging for prey, so they expose themselves to predation. When walking, goannas carry their bodies high off the ground and only a small portion of the tail near the tip touches the ground. While running the tail is lifted completely off the ground. When approached the goanna takes on a threatening position by arching its back, inflating its neck, and hissing loudly, and it can produce powerful side-swipes of the tail. The species is also reported to sometimes rear up on its hind legs in response to a threat.

To get warmer the Gould’s goanna basks in the sun, and it burrows to cool down.

All varanids are carnivorous and active predators. Gould’s goannas eat primarily mammals and reptiles but will also eat birds, amphibians, reptile eggs, insects, and crustaceans. Much of the vertebrate portion of their diet is probably scavenged from animals killed on the road. The goanna forages over long distances and often digs for prey in loose soil and decaying vegetation. They obtain most of their water from their food. Goannas walk with their snout held close to the ground while hunting for food. The long forked tongue flickers in and out transferring scents to the Jacobson’s organs. This way they can rapidly locate hidden prey, even if it is underground. They then use their sharp claws as well as their snout to dig out the prey. Cannibalism also occurs in the Gould’s goanna. Often this involves feeding on carrion.

Many goannas are used for food by Aborigines. They are also important animals in many Aboriginal cultures.

This reptile does no economic harm.

Varanids are protected from exploitation by state, federal, and international legislation. The conservation status is quite stable. Their largest threats are poachers, vehicle traffic, and raptorial birds. Habitat alteration and pollution must be kept to a minimum in order to maintain the species. (King and Green 1993)