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Rhacodactylus Ciliatus Natural History All of the Rhacodactylus species of gecko originated on the Islands of New Caledonia, which is located in the southwest Pacific Ocean about 1,200 kilometers (km) east of Australia and 1,500 km northeast of New Zealand. The main island of Grande Terre runs in a north-south orientation and is 16,372 square kilometers (km2). Unlike the much smaller neighboring islands, which are volcanic and relatively recent in origin, Grand Terre is an original piece of Gondwanaland. It separated from Australia 85 million years ago and has maintained its current isolation from other landmasses for more than 55 million years. Isolation and an ancient source of plant life are major factors leading to its diverse flora, but they are not the only factors. Grand Terre has an extremely diverse soil substrate, with ultramafics forming about one-third of the island. It is also diverse topographically and climatically. Grand Terre is the only high island of New Caledonia, with a mountain chain running down the center of the island and five peaks exceeding 1,500 meters (m). Many smaller ranges and valleys run counter to the island's north-south orientation. The soils of the Loyalty Islands to the east and Iles des Pines to the south of Grand Terre are largely from limestone substrates that resulted from the volcanic uplifting of corals when the islands were formed. Please click on the links below, then click on the map to learn more about New Caledonia. http://www.newcaledoniatourism-south.com/geography/index.cfm http://www.croixdusud.info/eng/bio_eng/zoo_eng.php The crested gecko (Rhacodactylus Ciliatus) is a species of gecko that was thought to have been extinct since 1866 until it was seen again in 1994, when two independant research groups "rediscovered" this species living quite happily and in relatively large numbers on the islands of New Caledonia, which lie approximately 1,200 km East of Australia in the Pacific ocean.These islands consist of one large island (Grande Terre) and lots of smaller ones. The geckos live on the islands of Grande Terre and the nearby Isle of Pines, as well as the isle of Komoto. There they inhabit forested areas, hiding under tree bark and in crevices during the day, emerging at night to hunt. Wild caught specimens from the initial collection were brought into Europe and the US and there it was discovered that the crested gecko thrive in captivity, they are easy to care for and breed readily.
All of the species of Rhacodactylus are arboreal and primarily nocturnal, but I have found that they can be active at dawn and dusk (crepusular) this is particularly true during the winter months, when daylight hours are shorter. Since I don't use any artificial light with my geckos, they do become active once the room gets dark. The generic name Rhacodactylus is Greek in origin; Rhakos, meaning ''spine'' and Dactylus meaning ''finger''. The specific name, ciliatus, is Latin; Cilia means ''fringe'' or ''eyelash'' and refers to the crest of skin over the animals eyes. The Rhacodactylus gecko as with most geckos do not have eyelids, instead a they have a transparent scale or spectacle which helps to keep the eyes moist, they will use their tongue to clean away any debris. Crested geckos are a medium sized, stocky gecko species. They are polymorphic by nature and have some ability to change colour-similar to chameleons, they will change colour depending on mood, temperature and time of day. They have a broad triangular shaped head with crests dorsolaterally up to the shoulder blade area. Over the eye ridges there are scales which resemble eyelashes, in fact some people call them Eyelash geckos. Approximately three inches long when newly hatched, they average eight to ten inches in length as adults. Hatchlings are miniature replicas of the adults, although the colour they exhibit when newly hatched is rarely the same colour they will be as adults. We know our geckos shed their skin, but why and how? Like human hair the uppermost layer of the geckos skin (the epidermis) is made up of dead keratin cells which since they are no longer growing are gradually worn off by external factors. As geckos grow throughout their lives, their skin must be shed at regular intervals, this occurs more frequently in young geckos as compared to adults. Crested geckos have adhesive lamellae (sticky pads) on their toes and have an interesting additional adhesive lamellae pad on the tip of the tail (which is prehensile) but how do these (sticky pads work?) Crested geckos feet have five highly flexible digits (scansors), each bearing toe pads consisting of arrays of hundreds of thousands of microscopic setae. Each seta splits into hundreds of 200 nm wide spatular tips. In their resting state, setal stalks are angled, and recurved proximally. When the toes of the gecko are planted, the setae bend out of this resting state, flattening the stalks between the toe and the substrate such that their tips point distally. This rather complicated adhesive mechanism operates according to the physical principle of adhesion (which means that two bodies cling to each other because of the attraction of their respective molecules or atoms) this is known as Van de Waals force. Crested Geckos can also display autonomy.(see Glossary) Unlike other species of Gecko, the Crested's tail will not grow back, once it has been thrown. Wild Crested Geckos rarely ever keep their tail. This ability is a defensive behavior, meant to distract predators while the Gecko escapes. Autonomy can also be the result of improper handling, fighting males, breeding, and stress. Stress can be the result of improper habitats, temperature extremes, improper handling, fighting, and breeding.
Crested geckos in general have very good temperaments and tend to be easily handeled once they are adult. Hatchlings and juveniles can be quick and jump around a lot but will usually tame down if handled gently for about 15 minutes a day (5 minutes at a time) Although more usually associated with the Rhacodatylus Auriculatus tail biting and eating can occur between crested geckos, as shown below. (photograph with kind permission of Andrew Gilpin L.A.C. Herps USA)
This is one of the youngsters I bought in, who had problems shedding from the start. I had to help her and in the end she was getting stressed and this is the result. As you can see the end of the tail where it was attached to the geckos body is shaped rather like a flower. It almost looks like one of those childrens shape sorting games, where only the exact shape will fit in the right hole. When the tail is dropped the capillaries to the tail will close almost instantly so there is little to no blood loss. The tails will move independent of the body for 2–5 minutes.
Housing Crested geckos are one of the easiest lizard species to maintain in captivity. They can be kept at temperatures of 70 - 82 degrees farenheight, and generally (except in very cold climates) do not require supplementary heating, providing there enclosures do not go outside the optimum temps. Overheating can be more of an issue with all the Rhacodactylus species and temps above 82-85 deg can be dangerous for these geckos, and even short exposure to temps above 85-90F could be lethal to your geckos. At these high temps they can display neurological symptoms (drop tails etc) and death could occur quite quickly. Humidity is fine at around 50-70%, and misting once a day is enough (more in very hot weather) If misting more frequently the enclosure must be allowed to dry out between mistings. They can withstand night time temps down into the mid 50's (as long as it is only night temps, and not all the time) My own geckos do not have any heat except room temps (even through the night in winter when the central heating is switched off ) They do not require any lighting except natural daylight as being nocturnal they spend the day hiding under leaves or in crevices. If however you are housing your cresteds in a basement (or any dark room) you should probably provide some lighting to simulate a day and night cycle. There has been a lot of talk about using UV with Rhacs, I am of the opinion that while it probably wont hurt, they do not require it to thrive. I have bred Rhacs since 2001 without UV and my geckos have never had a problem. A single adult crested gecko should be housed in a vivarium of at least 1 ft x 1 ft x 2 ft. A pair or trio should be housed in a vivarium of at least 18 x 12 x 30 inches (of course the bigger the better) Crested geckos are arboreal and prefer enclosures with a verticle format. Glass aquariums converted into vivariums are often good housing ( providing it is tall enough) as the humidity these geckos require can rot wooden vivariums eventually. The decor for crested geckos can include cork bark, branches and twigs (try different sizes, as it exercises their tails) from fruit trees, plastic or silk plants, live plants can of course be used, although specialist full spectrum lighting may be necessary for plant growth. Diet Crested geckos in the wild eat all forms of invertebrates and also as they are partly frugivorous they do eat a lot of rotten fruit. In captivity you can feed Crested gecko diet by T-REX, or the new Repashy superfood which is also by T-REX (and is also my preferred method) which comes in such flavours as rose, fig, banana and many other flavours, fruit mashes can also be given, a lot of people feed their cresteds banana's (which they love) but to much banana is not good for them as the high levels of potassium they contain can inhibit the absorption of calcium in the body. Many people are now using the Repashy superfood as it contains all the nutrients they need for a healthy life, they also seem to prefer the flavours of this over the Crested gecko diet. Some people still use fruit flavourd baby food and although the geckos eat it readily because it is so sweet, it does not contain all the essential nutrients they need to stay healthy, it also needs extra supplements adding to it to make it suitable (of course you are never sure how much to add?) Live foods can also be given in addition to the other foods, and if using the Repashy superfood you simply adjust the amount of base you are adding. Invertebrates that can be used include crickets, cockroaches, flies and small locusts. If you choose to give your gecko livefood, it should be gutloaded first (see Glossary) before being given to the gecko. The superfood (or whichever you choose) should be presented in a bowl large enough for the gecko to get its whole head into. Any insects should be dusted with a calcium supplement, hatchlings and breeding females should have supplementation every second feed and adults that are not breeding can have their food dusted about once a week. There are reports of some keepers raising several generations of crested geckos without any live prey at all, using instead only fruit and meat flavoured baby food mixtures with added vitamins, but this is not a natural diet for these geckos and it is not recommended. Crested geckos are avid eaters and can be offered 5 - 6 live prey items each, alternating with other diets. Crested geckos will drink from a water bowl if it is offered and one should be available at all times. In addition they should also be misted at least once a day especially the younger geckos, ideally more in warmer weather, this will help keep the humidity up around 60 - 80 percent, and will aid them when shedding, they will also drink the water from the leaves and walls. Different substrate can be used with crested geckos, such as orchid bark, cocoa fibre, cage carpet and for juveniles and hatchlings paper towels or kitchen roll is often best. Breeding Crested geckos are very prolific breeders, and usually have two eggs in a clutch and in theory could have up to 10-15 clutches per year, though 6-8 clutches is the more normal amount. The number off clutches laid depends on a variety of factors including; the age of the female (too young or very old cresteds) the quality of the diet, and most importantly, temperature. With first year breeders, dont get discouraged if you gets quite a few 'dud' (infertile)eggs, the hatch rate for first time breeding females is generally lower than that of old females. Infact sometimes the only way to get these geckos to stop laying is to lower the temperature in the enclosure to between 50 - 60 degrees F for a few months and reduce the amount of food offered. This will obviously be necessary if you are using added heating and/or lighting, my own cresteds do not have heat or light, and so tend to stop breeding themselves when the weather outside starts to cool down. Crested geckos are very easy to sex once adult. Males have extremely large hemipenal bulges and pre-anal pores, females have a slight single bump at the base of the tail above the vent. They tend to be sexable at the age of 6 - 8 months of age, but to be certain they should be left untill they are 12 months. Males that have been brought up together may be quite sociable but if a breeding male is already in residence then another male should not be introduced as fighting will occur. Crested geckos are sexually mature at around 9-12 months, although it is much better to wait untill around 18 months and at least 35g but the bigger the better for the health of the gecko (as they will lose some weight) before trying to breed them, this is especially important for the females who could become calcium deficient if bred to early. Crested geckos may not breed without a period of brumation. A cooling period of 3-4 months with a cage temperature of to 50 - 60 degrees seems to work well, our own geckos stop breeding themselves as the cooler weather arrives. During the cooling period food should be reduced to simulate winter arriving. Once the cooling period is finished then the daytime temperature should be allowed to reach 80 F, with a night time drop to the high 60's or low 70's. Increasing misting at this time may also induce breeding behaviour. When breeding starts the male will chase the female around and he will bite her usually on her neck crests, although if the female is unwilling he may bite her anywhere he can, such as legs and tail. After copulation (mating) has taken place you may notice the male licking his hemipenis, don't worry he is only cleaning them before they are inverted back into the hemipenal sac. Once a female is gravid it can be quite difficult to see the developing eggs in the females in the abdomen, unlike other gecko species such as leopard geckos, where the eggs are very obvious. Female cresteds are gravid for a period of around 30 - 40 days. When the female is ready to lay she will become restless and look for somewhere to deposit her eggs. At this time a laying box should be introduced. The laying box should be around 8 inches long x 5 inches wide x 4 inches deep, this should be filled with slightly damp peat (or your choice of sustrate) a lid may be used with a hole cut in it to allow the female access to the box, some females prefer the box without a lid. Once the eggs have been laid they should be transferred to an incubator (unless you are using just room temperature). Eggs can be incubated in either vermiculite or perlite or a mixture of both. If using vermiculite this should be mixed 2 parts substrate to 1 part water by weight but for perlite 1 part water to 1 part perlite again by weight. Eggs can be incubated at 65 - 80 F but temperatures above 82 F over long periods should be avoided. Youngsters will usually hatch in 65 - 120 days (but could be a bit longer) depending on the temperature you have choosen, when breaking free of the egg the hatchling will use its 2 tiny but very sharp egg teeth (see pic below) Hatchlings can be housed in plastic "Geo-tubs with kitchen roll used as substrate, a small plastic plant and some twigs and a small water bowl, I like to use milk bottle tops as there is less likely hood of the hatchling falling and and maybe drowning. Hatchlings are small and quite delicate for the first month. They should be fed every day on 2 - 3 crickets that are smaller than 1/2 width of the hatchlings head, and a small pot of T-Rex or Rhapashy Superfood should be offered about 3 times a week. Hatchlings should be lightly misted twice a day as they can dehydrate very easily. A pic showing mating between crested geckos.
These video's show just how noisy cresteds can be during mating, the first one was taken just after the introduction of the male, and in the second one she is telling him off. If you look carefully you will see he has bitten her tail (luckily she didn't lose it) http://s182.photobucket.com/albums/x219/sarasinorum/?action=view¤t=LucerneFemale.flv http://s182.photobucket.com/albums/x219/sarasinorum/?action=view¤t=Femaletellshimoff.flv This pic shows the egg teeth still in place, when the hatchling sheds its skin for the first time (within the first 24-48 hours) the egg teeth will usually be shed too, since they no longer serve any purpose.
These weights are for cresteds with their tails, and are only a rough guide. http://www.pangeareptile.com/forums/attachment.php?attachmentid=238&d=1145711144
The future Crested geckos are set to take over in the popularity stakes, as one of the easiest geckos to keep. as well as their good temperaments and stunning array of colours and patterns. With people studying genetics and trying to produce new colours these geckos are set to stay in the limelight for a very long time.
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