Arid Region
Goanna
(Sand Monitor)
What is a goanna?
Early white settlers saw these creatures and thought they were a type of
“Iguana” (which is the Guyana Indian name for Lizard) and over the years
this word transformed into the present word GOANNA. Goannas are in reality “Monitor Lizards,” of which Australia has 20 of the 30 species found
worldwide. One of the most common Goannas in Australia is the SAND MONITOR.
Sand
Monitor
General
In northern Australia it is active throughout the year; in the south, it is
inactive in the cooler months. Goannas are good tree climbers and strong
swimmers.
Description
Head and Body Length: up to 65.5cm.
Total Overall Length (with tail): up to 160cm.
A goanna has a flattened body, a tail ready to strike at enemies, stout limbs,
long digits and sharp claws. Goannas have a long neck with loose skin under the
throat which sags in some species causing it to look like the neck is bigger
than the head. A goanna has a snake-like tongue which flicks in and out.
Habitat
Goannas are largely terrestrial and dig their own burrow system but they will
readily take refuge in a tree if a burrow is not nearby.
Breeding
In northern Australia the goanna breeds in the wet season (summer); in the south
mating occurs in spring. From three to 11 eggs are laid into a long deep
nest-burrow which is plugged and concealed by the female. Hatchlings are seen in
mid to late summer and captive incubation of eggs (at about 30 degrees C.) has
taken from 169 to 265 days. This indicates that the eggs over-winter and that
young emerge in the following spring. 
Feeding
The goanna is an active forager which tracks down and digs out lizards (and
their eggs), insects, spiders, scorpions, centipedes and even small mammals. Carrion is taken when available and both freshwater and marine turtle eggs may
be dug up.
Hunting & Defense
Goannas saunter on four feet. They can also run quickly on their back legs and
take a two-legged posture when defensive.