The Ackie Monitor is native to the dryer regions of North-Western Australia. As their name suggests, Ackies belong to the monitor family of lizard. Its scientific name is Varanus acanthurus and it is sometimes referred to as the Spiny-Tailed Monitor or the Ridge-Tailed Monitor.
The Ackie Monitor is a medium sized lizard, growing to lengths of up to 2.5 feet. Over half of this length is made up of the tail. While this is large in comparison to many species of smaller lizards such as the Red Eyed Crocodile Skink, it is quite small for a Monitor.
Ackie Monitor Taxonomy
The Ackie Monitor belongs to the Varanus (Monitor) genus of Reptiles. The sub-genus that Ackies belong to is called Odatria. There are 19 recognised species that fall under this sub-genus including the Pilbara Monitor and the Kimberly Rock Monitor.
The Ackies Monitor was once divided into three sub-species, Varanus acanthurus acanthurus (Red Ackie), Varanus acanthurus brachyurus (Yellow Ackie) and Varanus acanthurus insulanicus (Island Ridge-Tailed Monitor).
After DNA analysis, it was indicated that the Red Ackie and the Yellow Ackie are in fact the same species and they are now both considered the one species again (Varanus acanthurus).
Analysis of the Island Ridge-Tailed Monitor has indicated that this monitor may need to be reclassified as a different species to the Red and Yellow Ackie entirely. These taxonomical changes are still being disputed so it is likely that more changes will occur in the future.
In this guide we are primarily going to focus on the Red Ackie and the Yellow Ackie. We are going to consider them the same species for now, but will discuss some of the differences between them.
Description
The Red Ackie has a dark brown base colour. It’s entire body and legs are usually covered in reddish orange spots, hence their name. The base colour of the Ackie tends to darken towards the tail of the lizard. The red and orange patterning also changes to bands or stripes, running across the lizard’s tail. The red spots often have a dark brown or black dot in the middle of them.
The Yellow Ackie is similar in appearance to the Red Ackie, with the primary difference being the colour. Like the Red Ackie, the Yellow Ackie has a dark brown base colour. However, the spots that run along the body of this lizard is yellow instead of red. Similar to the Red Ackie Monitor, this patterning tends to change to stripes along the tail of the lizard.
The Red Ackie Monitor generally grows larger than the Yellow Ackie. They tail of this monitor is also proportionally longer. While they are a medium sized lizard, they are considered ‘Dwarf’ Monitors, as they are much smaller than many other species of Monitor lizards such as the Asian Water Monitor.
Natural Habitat and Distribution
The Ackie Monitor is found throughout most of the North-Western section of Australia. Their range extends throughout most of Western Australia and the Northern territory.
The Red Ackie Monitor is primarily found in Western Australia. The type locality of the Red Ackie is the North-West coast of Australia. The Yellow Ackie Monitor is generally more common in central Australia. The type locality for the Yellow Ackie in Hermannsburg, Central Australia. This is just West of Alice Springs.
The Ackie Monitor can be found throughout most of Western and Northern Australia, but their range does not include the Northern tip of the Northern Territory (East of Darwin).
They share much of their geographical range with other common Australian species such as the Blue Tongue Skink, Olive Python and Black Headed Python.
These lizards prefer arid environments and are usually found in rocky outcrops or scrubland. The spend a large amount of time in rocky crevices to escape the intense midday heat. They will also retreat to deep humid burrows. These humid burrows are important habitats for the Ackie as they help them control their temperature and humidity requirements.
Ackie Monitors as Pets
This is a very curious and intuitive lizard. This is a species that is naturally curious and given the right habitat and care, it can be a great pet lizard. They are generally a docile species but will take a bit of time to get accustomed to you.
It is important to be patient with young Ackies. You should refrain from excessive handling until the lizard is comfortable with you. Try start by rubbing the lizard as opposed to handling it. You can then move to short handling sessions before gradually increasing the duration until the lizard is fully accustomed to you.
One important factor to consider before purchasing an Ackie is, do you have the space to house one of these lizards. This isn’t a species that will do well in a small enclosure. They are an active lizard and will need a large enclosure with plenty of space to move and climb.
Feeding an Ackie Monitor
While Ackies will generally eat a wide range of food, it is important to remember that just because your lizard will eat something, that doesn’t mean that the food is good for the lizard.
These lizards are known to eat cat and dog food as well as processed canned food. This source of food is not suitable for Ackies and should be avoided. There is a wide variety of other food to choose from when feeding an Ackie Monitor.
The most important part of a healthy diet is variety. This will ensure that your lizard is getting all the nutrients that they need. While dusting food is important, it should not be considered a replacement for a good varied diet.
Juvenile Ackies should primarily be fed insects. This should consist of a variety of different insects such as crickets, mealworms, locusts and small roaches. Food should be dusted with the calcium/vitamin supplementation.
Young Ackie Monitors can be given a small rodent occasionally as a treat. This should only be offered every month or so and only if the lizard is not overweight. If the lizard is on the skinny side, you can offer them rodents a little more frequently.
Adult Ackies can be fed a similar diet to juveniles. The bulk of the diet should consist of dusted insects. Again, the occasional rodent can be thrown in. Adult Ackies can also be offered raw turkey on occasion if they are not on the heavy side.
As Ackies are an active lizard, you can feed them insects daily. If they are starting to gain weight, reduce the number of insects that you offer each day.
Ackie Monitor Housing
The Ackie Monitor is an active lizard and will therefore need a large enclosure to give it enough room to roam around. As these lizards grow to an average length of around 2ft, the minimum sized enclosure for an adult should be 4ft x 2ft x 2ft.
Keep in mind that this is the minimum size you should be using. If you can offer the animal a larger enclosure you should. When it comes to Ackies, the larger the better. These active lizards will utilise every square inch of space that you give them.
In the wild, Ackies will dig and burrow in the soil so if possible, you should try to give them a tall enclosure with a deep layer of substrate. One way of doing this is to give them a 3ft tall enclosure. The first foot should be taken up by the substrate, leaving them 2ft of open space (height wise).
These lizards rely on a humid substrate to keep hydrated so wood isn’t a good choice when it comes to cage material. This is usually the most popular choice when it comes to large custom-built enclosures.
A glass enclosure is ok for these lizard’s, but large ones are very expensive. It can also be very difficult to find a glass enclosure that exceeds 4ft in length as they are not readily available in most pet shops.
We find that a custom build enclosure is the way to go, as it allows you to build a large enclosure to your own specifications without breaking the bank. Instead of using wood, it is better to build the enclosure out of sheet PVC.
PVC is a great material for building reptile enclosures and it’s becoming more and more popular in the hobby. You can build a custom PVC enclosure the same way you would build a wooden enclosure, but there are added benefits.
PVC is a great insulator, so it is much easier to control temperatures than it is in a glass enclosure. Keep in mind that these monitors will need a large enclosure. It is very difficult to provide the correct thermal gradient in a large glass enclosure.
Unlike wooden enclosures, PVC does not rot or warp when it gets damp. This will greatly prolong the lifespan of your enclosure. As Ackie Monitors need a humid substrate, PVC is the preferred choice when it comes to cage materials.
Light and Heat
Ackies live in the arid regions of Australia where it gets really hot. These lizards also bask in the sun, utilising the Ultraviolet rays from the sun to synthesise Vitamin D3. These conditions need to be replicated in their enclosure.
These lizards need a very hot basking spot. Aim for a basking temperature of 120F. This can be achieved with an overhead ceramic heater. Overhead heat is better for Ackies as they are a basking lizard.
The ambient temperature at the cool end of the enclosure can drop to around 70F. The cool end should not exceed 80F in order to provide your monitor with enough of a thermal gradient to appropriately regulate their body temperature.
Ackie Monitors need a lot of UVB. This can be provided by placing a UVB Bulb at one end of the enclosure. The lizard can then move away from the bulb to an area where there is no UVB if it wants.
An alternative option is to use a UVB tube in the enclosure. If you use this method, place the tube towards the back of the enclosure. This way the monitor can move away from the source of the UVB if it wants to.
Whichever method you choose, you need to ensure you choose a bulb that emits enough UBV. These lizards like high levels so choose a bulb that emits 10% or 12% UVB.
You can buy a UV index monitor to read the levels of UV in the enclosure. However, these are very expensive. If you follow the guidelines of the lights specifications, you should be fine. These guidelines will include distance from light to floor, replacement frequency etc.
Any lights in the enclosure should be turned off at night. Aim for around a 12hr day/night cycle. This can simply be achieved by turning the lights off at night and on again in the morning. Alternatively, you can have the lights connected to a timer and this will be achieved automatically.
Ackie Monitor Substrate
Humidity is very important for Ackie Monitors. A humid substrate is vital to keep Ackies hydrated. A large freshwater bowl should always be present in the enclosure also.
These lizards love to dig so you should be aiming for a deep substrate that is loosely packed. This substrate should hold humidity well without moulding. There are a number of commercially available substrates that fit these requirements.
We recommend a soil-based substrate such as Eco Earth or a Coconut Fibre substrate. Both substrates hold humidity very well and will allow your monitor to dig and burrow.
You should make the substrate as deep as possible to promote digging behaviour. If possible, offer your monitor around a foot of substrate. This is especially important for gravid females. If a female does not have an appropriate lay site, she may hold onto her eggs and become egg bound.
Handling an Ackie Monitor
Ackie Monitors are very curious and intuitive animals. This is great as it means they can become very accustomed to handling and over time can enjoy handling sessions and interacting with humans.
As with any young lizard, you should give your monitor time to acclimatise before trying to handle them. The less stress the lizard is under before you interact with them, the easier the encounter will be.
If you have a skittish monitor, try to build up a bit of trust first. You could try offering it food off a tweezers or gently rubbing them while they are in the enclosure. A less invasive approach for a while might help the Ackie to relax.
Once the lizard seems relatively relaxed, you can begin to take them out and handle them. Handle sessions should be short at first to reduce the stress placed on the lizard. This can be increased over time.
Many Ackie Monitors are puppy dog tame and will love spending time out of their enclosure. Some will even trust you almost immediately and will need very little persuasion to come out for a handling session.
Ackie Monitor Breeding
As with any reptile, you must ensure that both the male and female are in good health and appropriate weight before trying to breed them.
There are a number of different ways you can introduce the male. Some people cycle a male between females. Others keep a trio together and some decide to keep a pair together during the breeding season.
There is no correct method and so just go with whatever works best for you. It is important to separate the male for a day or two at a time. This will give the animals time to rest and destress. It will also reignite interest in breeding.
In captivity, Ackie Monitors can be bred year-round. Again, it is important to assess the health of your monitors before breeding. If they are under weight, separate the male and don’t introduce them until they are at a healthy weight for breeding.
You should give the Ackies as much privacy as you can while mating. During this time, you may observe them locked in the mating position for extended periods at a time.
If you are not using a deep substrate in your enclosure, you will need to add a nest box in order for the female to lay her eggs. This lay box should be at least 12 inches deep.
You will notice a change in the behaviour of your female. This is a good indication that she is gravid. She will start to dig in the substrate, searching for a good nesting spot. A gravid female also has a ferocious appetite. She will also look noticeably larger and appear bloated.
This is a good time to get your incubator set up. Ackie Monitor eggs can be incubated between 85-87F. The female will generally lay around 20 days after mating.
After laying, the female will appear much thinner that before with a more slender tail. This is a tell tail sign that you need to search for eggs.
Fertile eggs are generally white in colour and oval in shape. You should incubate them on a damp substrate such as vermiculite. All going well, babies should emerge after 90-120 days.
Hatchling Ackies can be housed in their own individual enclosures. For the first couple of weeks they do great in tubs with a wet paper towel substrate. These conditions allow you to closely monitor the babies while ensuring they stay hydrated.
After they are established and feeding well, you can upgrade them to a mini version of an adult enclosure. This can include substrate and cage decor. Keep an eye on juveniles to ensure they are feeding well and kept hydrated.