The Jacky Lizard (also known as the Jacky Dragon or the Tree Dragon) belongs to a large genus of Australian Dragon lizards. It is pale grey to dark brown in colour with black patches along the middle of the back and two paler stripes on either side of these two dark patches.
Jacky Lizard, Amphibolurus muricatusPhotographer: Peter Robinson / Source: Wildlife Profiles
All members of the genus Amphibolurus have very variable scales, but the Jacky Lizard has particularly large and prominent scales along its back in rows from the neck to the base of the tail and spiny scales on the sides of the neck. Jacky Lizards have a snout-vent length of about 100 millimetres and can weighs up to 60 grams. The tail is very long (up to about 200 millimetres) and the lining of the mouth is bright yellow.
Jacky Lizard, Amphibolurus muricatusPhotographer: Peter Robinson. Source: Wildlife Profiles.
Jacky Lizards feed on insects and other small creatures (arthropods). Males usually have a larger head than females. Jacky Lizards show crypsis in their appearance. This means they disguise their body outline by colouring (a form of camouflage).
Adult females probably breed every summer and may have 3-9 eggs. These eggs are laid in shallow burrows and the sex of the young is partly determined by the nest temperature.
The lizard (like many reptiles) is dependent on sunlight to raise body temperature for normal activity.
Jacky Lizards are found throughout south-eastern Australia from South Australia to south-eastern Queensland. They are mainly found along the coast and ranges in dry sclerophyll, rocky ridges and coastal heathlands. They may be seen most readily in areas of low vegetation.
The distribution of the Jacky Lizard in VictoriaSource: Museum Victoria (www.museum.vic.gov.au/bioinformatics)
Cogger H. 2000. Reptiles and Amphibians of Australia. Reed Books.
Wilson S. & Swan G. 2003. Reptiles of Australia. Princeton University Press.
Percy won't be causing these patches. They are more likely to be from domestic pets (or neighbourhood cats if you don't have any pets of your own). Lizards don't produce urine on its own, instead they excrete droppings made up of uric acid crystals along with faeces - small, compact and discrete droppings that don't kill grass.
Hi Julian - our Live Exhibits manager says that the most likely problem is metabolic bone disease, in which their bones degenerate due to lack of calcium or UV light. Either way it sounds like the lizard needs to be taken to the vet as soon as possible.
The gestation period - ie the time between mating and egg laying - is 4-6 weeks in this species.
The incubation period for Jacky Dragon eggs depends on temperature - at about 28 degrees Celsius the eggs take 55-60 days to hatch. The temperature also determines the sex of the hatchlings, with males being produced at temperatures of 20-25 degrees, and females above and below these temperatures.
Without extra heating at this time of year, reptiles will slow down and don’t require much food at all. With no heating they will go into hibernation (brumation) and cease all activity (including eating) until spring. Reptiles need to brumate on an empty stomach, otherwise food will sit in the digestive system for several months without being properly digested, causing the food to turn rancid with negative (possibly fatal) effects on the animal. If your lizard is generally in good health and otherwise eats well, you can turn its heating off and allow it to brumate as Jacky Dragons naturally do in the wild.
There are few if any reports of Jacky Dragons (Amphibolurus muricatus) eating other lizards, but as a general rule it's not wise to house larger lizards with smaller ones, particularly small lizards of a different species. Captive animals will sometimes feed on prey that they would never feed on in the wild, simply as a function of captivity.
Jacky Lizards are found widely and are not endangered. You might be interested in checking out Museum Victoria’s bioinformatics page – this site contains lots of information including distribution maps on Victorian lizards including the Jacky Lizard
Jacky Lizards may be kept as pets if you hold a Basic Wildlife License, and more information about that can be found at the Department of Sustainability and Environment. A reputable breeder can give you more detailed information about the needs of your pet.
It is difficult for us to say what might be wrong with you lizard. We suggest you take your Lizard to a vet for consultation.
It’s good that you thought of the dragon’s welfare when considering its release. It’s not a good idea to release the Jacky Dragon when the temperature is too low, as it might not have the energy to find suitable shelter. You can let it go when the outside temperature reaches 20 degrees - until then it sounds like you’re looking after it well.
Dragons do not voluntarily drop their tails or regrow them as some skink species do, so a cut on the tail can be a serious health issue. If you're concerned about it you should take the dragon to a vet. Your local vet may be able to treat it or refer you to a vet that specialises in reptiles
Hi Klobasaurus, about 80% of the diet of Bearded Dragons in the wild is animal prey. This is mostly insects, but also includes small rodents and other lizards. If the size difference between your Bearded Dragon and Jacky Lizard is significant, it would be safest not to house them together.
The Jacky dragon is too small to sex but the Bearded dragon should be fairly straightforward. In adults the best indication is the size of the femoral pores (a row of pores running along the underside of the rear leg). These are quite obvious and large in adult males but are quite small on females. If you search 'femoral pores' on the internet it will give you a good indication of what to look for.
A two foot tank is probably just large enough for a Jacky dragon, but the lizard may be too hot with that much lighting. A 30w or 40w (preferably 30w) would be better than the 50w. The light should be in a corner of the tank so the lizard is able to move away from it, and it should be used as a basking light rather than a viewing light (i.e. only on for a certain period of the day). The lizard's behaviour should give you and indication - if it hides away when the light is on, it might mean it's too hot. If it comes out and sits under the basking light, it should be just right.
And remember that at this time of year the lizards are cooling down for winter and not getting as much sun as earlier in the year.
Male and female head size and shape is identical in Jacky dragons and the only way to tell the difference between sexes are the pre-anal pores on the insides of the thighs on the hind legs. You'll probably need to search 'pre-anal pores' online to get an idea of what to look for. Males have four pre-anal pores, females none.
Hi Tyler, the staff in the Museum's Live Exhibits Department have said they suspect she may be starting to moult, but could only confirm this if you were able to send some photos. You are welcome to take some images and email them to firstname.lastname@example.org
The Jacky Lizard can grow to approximately 300mm in length (this is including the tail).
In regards to identifying the difference between males and females, the following website will assist you: http://en.allexperts.com/q/Reptiles-704/jackie-lizards.htm. Also, some of the comments by the Discovery Centre above have further explanations of identifying the sex of Jacky Lizards.
The Jacky Lizard has a lifespan of up to 6-7 years.
It’s hard to tell exactly what the problem with your Jacky Dragon might be. Our best suggestion is that it may be slowing down for the middle of winter and would prefer to be left alone for a period. If given the option, Jacky Dragons often take shelter for a week or two at this time of year even in captivity, then become more active as the weather outside warms up.
This might explain its reduced feeding and unusual behaviour. It might also be better to turn the heat pad off and offer an overhead basking light instead, which would give the dragon the choice of moving into or away from the warm spot as it felt the need. This is probably a better option for the longer term as well, not just during winter.
That’s all we can suggest at the moment. We hope the dragon improves rapidly, and if you’re still concerned about its health, the best way to be sure is to visit a vet.
Hi Jonathon, the worm you observed could be a parasitic worm. They can have impacts on the health of your lizard, just like intestinal worms can have on humans. The best thing to do is to keep the sample of poo and get it to a vet who can do what is called a ‘faecal float’, they do this to determine the types of parasites that are living in your animals system. Once they know the species they can work out if it is dangerous for your Jacky and whether treatment is required. If you do need to treat the animals for parasites you will have to treat the whole population as the others will possibly have the parasite as well.
Here at the museum one thing we always do to try to minimise parasites is removed any poo from the enclosure as soon as it is noticed. This minimises the chances that parasites will be given a chance to establish, as the lizards won’t accidently eat their own poo, or feed crickets and cockroaches.
Hi Alison, You'll need to artificially incubate the eggs. The male should be fine kept with the female during this period however if he is still trying to mate with her and causing any stress he should be removed. Firstly you need to provide the female with a laying site, this can be an ice cream container or equivalent with a small entry hole cut into it. Have the container filled with either moist (not too wet just moist) coco peat or sand, or a mix of both works well. Keep an eye on her, she will be close to laying when she starts digging in the container. When she lays the eggs she will bury them, gently dig them up with a spoon, take as much time as you can as they're a soft shelled egg that is very easy to damage. It's important never to rotate the eggs, this could kill them as the embryo must develope with the air bubble at the top of the egg (if it is turned it will drown). An easy way to ensure they're not rotated is to mark the top of each egg with a soft grey lead pencil. Eggs are most commonly incubated in perlite or vermiculite, these are minerals that hold moisture pretty well. They can be purchased from hydroponic shops or sometimes specialist reptile petshops. It can be hard to find so try and get some asap so you are ready when the eggs are layed. Set up a tub about 1/3 full of the substrate (perlite or vermiculite) but first weight the substrate and add the same weight of boiled water. So there is a 1:1 ratio of substrate to water by weight. Then your tub is ready for the eggs, when transfering the eggs make an indentation with your finger for the eggs to sit in. The eggs then need to be kept at about 30 degrees celsius to hatch. If you want to do more research into dragon breeding, there are plenty of online resources for bearded dragons (which can also be applied to jacky dragons), just try googling bearded dragon care sheets.
Hi Kimmie, it is not always 100% correct but in general male lizards have larger pores around their anal region. These are located on the underside of the animal around the lower limbs. To reduce the stress of them both living together make sure you provide adequate perching space so they can both be comfortable in the basking site without being in each others way.
Hi Krystal-Lee, housing lizards like yours you do need to be a little careful in a shared enclosure. If your female was not gravid I would recommend that you provide adequate perching spaces and basking sites so they are not competing for the same one spot to warm up. Since you are waiting for your female to lay eggs it may be a good idea to separate her so she can have some peace and quiet to settle and lay those eggs.
Your Jacky Lizard may well have more eggs inside her that need to be laid, or she is just a lizard that is in very good condition. Make sure that she has some substrate (dirt and sand) that she can dig into to lay eggs if she needs to. As long as you provide the right conditions to lay the eggs hopefully she will have no problems. If you find that she goes off her food and is uninterested in basking and feeding possibly you may have a problem and a visit to the vet may be warranted. Sometimes lizards can become egg bound – where an egg gets stuck in the body for some reason – this is quite unlikely but is worth considering if her health starts to fail.
We’d be happy to see the photos if you send them through to us. Please send them to the Discovery Centre. Thanks!
Hi Katie - Jacky Dragons do have the potential to bite – they are a predator and their bite is strong enough to break the skin so you do have to be a little careful. The best thing for the lizards, and your son, is to try to stop your cat from getting to the lizards. They are great wildlife to have around the place.
Hi Shannon, It would be dependent on incubation temperature. For bearded dragon eggs incubated at 28 degrees you might expect them to hatch in about 55-60 days. Hope this helps.
Hi Fiona, the best way to sex a Jacky Dragon is to look on the underside of the body between the hind legs. Males have visible pores there that they use to scent with. These pores excrete a waxlike material that they leave a trail of. The other way males are different from females is that you can observe a swelling at the base of the tail where the hemipenes are bulging, although to recognise this sexual difference it is often better to have one of each sex to compare.
Hi Helena, it is best not to release it at this time of year – it would not do well. You could either hold onto it until the weather warms up in spring and then release it near where it came from, or hand it over to a licenced wildlife carer. This link helps locate various carers within regions across Australia.
Hi Koda - Thanks for your question. We would advise to be careful with the amount of mince your Jacky is fed – Mince it has a much higher fat content than most of the food Jacky Lizards would naturally eat. It could cause obesity and other problems over time. Maybe just stick with the insects as food, and if you really want to give it mince on do so once a fortnight as a treat.
Hi Carman, you are very lucky to have a healthy population of Jacky Lizards – it indicates that you have a nice little eco-system in the nursery. Jacky lizards however, would play no part at all in keeping snakes away, in fact many snakes would eat them so they would be more of an attractant than a deterrent
According to our Live Exhibits folk, the first thing to check is that the enclosure temperatures are ok. There should be a gradient of temperature too, i.e. a cool end and a warm end. During the day, the cool end should be in the low 20s, and the warm end under a heat lamp should be around 30 degrees. If the living conditions are all ok and it still isn’t eating it is time to get vet advice.
Hi Daniel - Museum Victoria does offer a free identification service. Please send us your identification enquiry about the lizard you saw when kayaking here. You can attach the image you took and, prior to sending us your enquiry, please read our identification guidelines.
Hi Joel. What a great name for a Jacky Lizard! Unfortunately it is not legal to keep wild caught animals such as these and you should release the lizard where you found it. If you do want to keep a Jacky Lizard as a pet you can buy one from a breeder, who can also give you more detailed information about the needs of your pet. You also need to obtain a Basic Wildlife License. More information about that can be found at the Department of Sustainability and Environment.
Hi there Laura. We referred your query to our Curator for Herpetology. She noted it is hard to identify the lizard hard to tell from the photo: “a lot of juvenile agamid lizards can look the same. If it has a row of small spines along each side of its body and a row of small spines across the back of its head and grey oval-shaped patterns on its tummy, it could also be a baby bearded dragon”. If you are able to take additional photos of the lizard or provide information about where you saw it you are most welcome to make a formal identification enquiry. Prior to sending us your enquiry, please read our identification guidelines.
Hi all, recently being visted by a baby lizard. Trying to figure out the species, I think based on photos its a Jacky but unsure, heres a photo of the little guy, this is driving me mad! http://tinyurl.com/yhex3t5 Thanks
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Hi Joshua, Jacky Lizards eat insects. Have a look at the post above, you will find details about their eating habits and keeping them as pets.
As you'll see from the infosheet above, and the previous comments, the Jacky Lizard eats insects. Jacky Lizards may be kept as pets if you hold a Basic Wildlife License, and more information about that can be found at the Department of Sustainability and Environment. A reputable breeder can give you more detailed information about the needs of your pet!
Hi William, two to three times a week would be ok but young growing lizards could be fed as often as they’ll eat. Therefore the lizard could be offered food every day. The critical thing is that the crickets are dusted with calcium powder,and the lizard is provided with a suitable level of UV. If not, bone growth deformities may result. Reptile UV lights can be purchased through most pet shops which deal with reptiles.
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