Question: Last night I saw this lizard in my Melbourne garden. It looks just like a gecko, but I didn’t think geckos lived this far south. I know tropical frogs sometimes make it to Melbourne in shipments of bananas. Could this gecko be a stowaway? I’m worried the gecko won’t survive a Melbourne winter. Should I try and catch it?
Photographer/Source: Michael Kearney
Answer: The gecko you saw in your garden is a Marbled Gecko, Christinus marmoratus.
Marbled Geckos are actually quite common in some parts of Melbourne (there is a huge population in the Melbourne Cemetery), but people rarely see them because they are nocturnal. You’re most likely to find them between pieces of wood in your garden, in your roof or even indoors behind a picture frame.
A Marbled Gecko
Photographer: Peter Robertson / Source: Wildlife Profiles Pty Ltd
Even if you never see a gecko in your house or backyard, you can often tell they’re around by the signs they leave behind. Marbled Geckos deposit tiny black and white poos on the surfaces they walk across (their poos look a lot like small bird poos).
Unlike most reptiles, Marbled Geckos don’t leave their shed skins behind for keen naturalists to find. They eat them! They also eat spiders and insects such as cockroaches, so they are useful little creatures to have around the home.
Marbled Geckos are the only geckos that are found in Melbourne. It is unknown whether this species originally occurred in the area; it is possible that they were unintentionally introduced to the city by people bringing in firewood and garden rocks from other parts of Victoria.
Many reptiles would struggle in Melbourne in winter; moving, digesting and reproducing become more difficult for reptiles when it gets cold. Marbled Geckos, however, can be active at temperatures as low as six degrees. In the dead of winter they may only come out for a short time after it gets dark and then find shelter when it gets too cold.
In winter, Marbled Geckos select daytime retreats that will allow them to warm up – thin sun-baked rocks, roof tiles or north-facing tree bark. In summer they choose deeper retreats.
We would not recommend trying to catch the gecko in your garden. You could give it a nasty fright and cause it to drop its tail (a useful defensive strategy allowing the rest of the body to escape). Geckos store fat (and water) in their tails. While your gecko will cope perfectly well with the cold in winter, it will struggle without its winter stores during this period when food is scarce.