chatty companions

Geckos might be small, but they make their presence felt, says

Another reptile hitching a ride in cars and trucks in summer is the Asian house gecko (Hemidactylus frenatus). On a recent road trip, my wife and I could hear its distinctive chuck-chuck-chuck every time we stopped in a town after dark. This is a familiar sound in the Northern Territory, Queensland and many places in the Indo-Pacific region.

These little sticky-toed lizards from South-East Asia have been in Australia for several decades and are moving further south as the climate warms. They are most likely seen at petrol stations, markets and other places where trucks stop to unload cargo, especially at night when the bright lights attract flying insects, providing food. The geckos can be transported to new destinations after hiding in crates and building materials during the day to avoid sunlight.

Sometimes their eggs also hitch a ride. Unlike most lizard eggs, which have soft shells, these geckos lay tiny, hard-shelled eggs. When a female lays eggs in a hiding place she thinks is safe, others are likely to follow. It’s not unusual for electricians to take apart second-hand electrical fittings, such as lighting fixtures, and discover more than a dozen of these tiny eggs waiting to hatch.

Research is under way to measure the impact of these geckos on our native house gecko (Gehyra dubia), which is much less common. Australian homes are mostly occupied by the Asian species (above) and the introduced mourning gecko (Lepidodactylus lugubris), an all-female species. In areas where these two occur together, the number of mourning geckos declines. The Asian species is more aggressive, as suggested by its loud chatter, which sounds like a fighting or territorial call, so perhaps it simply chases the other ones away.

If you’re travelling north of Sydney and stopping overnight in towns along the way, keep an eye and ear open for these chatty little lizards.