lizard

Big Desert Adventures: Part Two

I’ve just returned from my first foray into Victoria’s spectacular Big Desert, and it was every bit as successful as hoped. Currently, there are 35 predator cameras and 35 prey cameras deployed across 35 sites within the Big Desert Wilderness Park, Big Desert State Forest and the Wyperfeld National Park. It really is a beautiful region, hosting a range of ecosystems not seen anywhere else in Victoria.

A picturesque Big Desert sunrise. Photo: William Geary

A picturesque Big Desert sunrise. Photo: William Geary

With any luck, there’ll be a nice array of critters dancing in front of my cameras as you read this. Specifically, at each location I’m targeting Dingoes, Red Foxes and Feral Cats with the predator cameras and a bunch of small mammals (including the Silky Desert Mouse, Mitchells Hopping Mouse and the House Mouse) with the prey cameras. Why these animals though? Well, have a read of my last article describing the background of my project in a little more detail.

You might be wondering what these cameras I’m speaking of look like, so here’s some examples below. The movement of heat (i.e. a body) across a detection zone triggers the cameras, taking video or photos in response. However, that’s where the similarities end; the predator cameras are outward facing, in order to observe larger animals. On the other hand, the prey cameras face downwards as this aids the identification of many small mammal species. Without the help of camera traps, there are quite a few species I wouldn’t even be able to detect, making them an essential tool for any wildlife ecologist. 

The downward facing prey camera, complete with delicious peanut buttery bait. Photo: William Geary. 

The downward facing prey camera, complete with delicious peanut buttery bait. Photo: William Geary. 

The outward facing predator camera in some early successional heathland. Photo: William Geary

The outward facing predator camera in some early successional heathland. Photo: William Geary

In addition, I surveyed for predator scats at each site, collecting nearly 100 samples across nearly 90km worth of transects. Helpfully, Canid and fox scats are generally very easy to spot as they tend to be placed quite prominently in order to mark territory. These will give me another insight into what habitats the local predators are using most. We’ll also be sending the scats off for diet analysis to find out just what’s on the menu in the Big Desert for our furry carnivores.

At our last site we got a true indication of just how merciless fire can be in the mallee (see the photo below). With absolutely nothing left, save for one or two coppicing Eucalypts, one really gets an idea of what the phrase ‘resetting successional trajectory to year zero’ means. Or, in layman’s terms, clearing the ecological slate and starting from scratch. There are very few places in Victoria where succession can be viewed as vividly as in the mallee.

Fire can be absolutely devastating in the Mallee, leaving very little behind. Photo: William Geary

Fire can be absolutely devastating in the Mallee, leaving very little behind. Photo: William Geary

Having traversed a myriad of sandy 4WD tracks, both in the car and on foot, one really gets an appreciation of just how vast and untouched the region is. The sensation of looking out from the top of a dune, with not a single man-made feature in sight is something pretty special. This was compounded at one point with three or four Wedge Tailed Eagles flying overhead whilst gazing off into the distance. Importantly, the Big Desert’s vastness shouldn’t be mistaken for emptiness, with the place absolutely crawling with wildlife.

The vast landscape of the Big Desert. Photo: William Geary

The vast landscape of the Big Desert. Photo: William Geary

Throughout our expedition we managed to happen across a range of reptiles (Mallee Dragons, a Burton’s Legless Lizard & Stumpy Tailed Lizards) as well as the standard mobs of Emus and Western Grey Kangaroos. However, perhaps the most fun aspect was deciphering the origin of the plethora of animal tracks found in the sandy soil. Everything from echidna and dingo to legless lizard and emu tracks were spotted. Following one particular track in the sand resulted in a particularly excellent encounter with a Burton’s Legless Lizard. A definite trip highlight.

Given the recent cold snap, the reptiles will be well and truly hidden away when the time comes for the next Big Desert Adventure. Despite this, I’ll hopefully have some exciting camera trap pictures to share, as well as more photos of the beautiful landscape that is Victoria’s mallee. 

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!