Snail Extermination and Slug Annihilation: The Blue-Tongue Lizards (Tiliqua sp.)

These surly animals are common residents in many Melbournian backyards, but due to misinformation, many people dislike and are even afraid of Blue-Tongue Lizards. Contrary to popular belief, there is a lot to like about these grumpy-looking reptiles.

Growing up to 30 cm long, Blue-Tongue Lizards are the largest members of the Skink family. They are found in a wide range of habitats, including coastal and montane regions, sclerophyll forests and urban areas. Eastern Blue-Tongue Lizards (Tiliqua scincoides) are common throughout Melbourne, especially in the western and northern suburbs, whilst Southern Blue-Tongue Lizards (Tiliqua nigrolutea) are more common in the eastern suburbs.

Also known as Common Blue-Tongue Lizards, Eastern Blue-Tongue Lizards are recognizable due to the broad, dark brown or blackish bands across their back and tail. In contrast, Southern Blue-Tongue Lizards (also known as Blotched Blue-Tongue Lizards) have large pink, cream or yellow blotches on their back. Furthermore, Eastern Blue-Tongue Lizards have a silvery-grey background colour, whilst Southern Blue Tongue Lizards have a darker, browner background colour.

An Eastern Blue-Tongue Lizard rests amongst leaf litter. 

An Eastern Blue-Tongue Lizard rests amongst leaf litter. 

These lizards are often seen basking in the morning sunshine, warming themselves up so that they can forage and hunt in the heat of the afternoon. During the winter months, these lizards enter a dormant phase, but it is not true hibernation. On warmer days during this period, Blue-Tongue Lizards will emerge from their shelters to bask, but will not feed until the weather warms up for good.

Blue-Tongue Lizards use their brightly coloured tongues for defence. When threatened, these lizards will approach the threat with their mouths wide open, and may even hiss. In the event that a Blue-Tongue Lizard is caught by a predator, it can drop its tail to increase its chances of escape and survival. The stump that remains rapidly heals, and a shorter, regenerated tail grows to replace the lost tail. Predators of Blue-Tongue Lizards include large predatory birds, snakes, and feral cats and dogs.

Contrary to popular belief, these lizards are not venomous or particularly aggressive, but can deliver a painful bite if they are harassed. In fact, Blue-Tongue Lizards are a good animal to have in your backyard, especially if you are concerned about the number of slugs and snails in your vegie patch or garden bed. Blue-Tongue Lizards feed mainly on these creepy crawlies, as well as beetles, other insects, fruits and flowers.

To encourage Blue-Tongue Lizards into your backyard, add a few rocks or logs to any sunny spots, and make sure that there is some shelter near by, such as low shrubs or a clay pipe. This way, the lizards will be able to bask, but also escape to safety if they feel threatened. In addition, keep the use of snail bait to a minimum – this is toxic to Blue-Tongue Lizards, and, with any luck, the lizards will eat those pesky snails and you won’t need the snail bait anyway!