Crested geckos care sheet

Crested geckos care and breeding, the basics
Taxonomics: Class: Sauria Superfamily: Gekkota, Family: Diplodactylidae, Species: Correlophus ciliatus, Guichenot 1866, old synonym: Rhacodactylus ciliatus. See Bauer, A.M., Jackman, T.A., Sadlier, R.A., Whitaker, A.H. (2012) "Revision of the giant geckos of New Caledonia (Reptilia: Diplodactylidae: Rhacodactylus)". Zootaxa 3404: 1 – 52 for the name change.
Common English name: Crested gecko, crestie.
IMPORTANT NOTE: what follows reflects my own experience, practice and thoughts about this species. There is not just one way to care about a given species, so be aware it is a personal care sheet, out of any mercantile considerations.
This species has been known to science for more than 150 years. In spite of this, they have been “rediscovered” in the wild by scientists- see Seipp & Henkel (2000, Rhacodactylus, Biology, Natural History and Husbandry , Chimaira ed., a must-have book for all New Caledonian geckos keepers, now sold out but appearing now and then on classifieds from the Internet)!
This can be explained by the difficulty to reach their natural habitats- primary rainforest patches and gallery forests near rivers in New Caledonia mainland. They are endemic to this French overseas territory and occur on the Southern half of the mainland as well as on Pine Island. Most specimens in the wild have lost their tails.
Since 2009, imports from New Caledonia are strictly forbidden(Code de l'environnement de la Province Sud (Délibération No. 25-2009/APS, 20 March 2009)). So, their import was only possible between 1993 and 2009, and NOT for the pet trade but for scientific purposes only. I have precise data from New Caledonian local authorizes which corresponds to permits delivered for the exportation of dead or alive specimens for scientific researches purposes. I am not allowed to give precise data in public, but all I can say is that over that period, less than 200 live specimens were legally allowed to leave New Caledonia. If you withdraw from that number specimens which did not survive the trip or were put down for scientific purposes, it really leaves a very small genetic pool.

Now, crested geckos live in rainforests. The thing is, there are many types of rainforests, not all of them are warm and filled with a variety of prey all year long. New Caledonia mainland is a 250 mile long island, at the East of Australia, some hundreds of miles away from the latter. The local climate is rather warm and humid, but NOT in the microhabitats where crested geckos live which is a lot cooler than in the Island capital city Nouméa. Prey insects are not available all year long, so they have adapted to a varied diet which includes pollen, flower nectars, smaller geckos (including their own babies and skinks of the Austrocaledoniscincus genus), small nesting birds and baby rodents. So, in the wild, their nutritional spectrum is quite varied but mainly consists of arthopods, i.e. insects, worms, caterpillars, spiders…
They are themselves prey for bigger geckos (R. leachianus) which explains they have a different vertical distribution in the wild: while “leachies” are mostly found high above the ground near tree tops, crested geckos generally live in bushes and on small branches between 5 and 10 feet (1,5 to 3 meters) above ground level.
They are listed in Appendix D of the European Community, which means no particular paperwork is needed but that the EU does care about their conservation status, through the CE338/97 regulation and its ulterior modifications. The IUCN lists them as vulnerable, due to the small range they live in and immediate threats such as human activities (nickel mining, tourism, bushfires) but also because of invaders such as red fire ants which wreak havoc on the local fauna and flora. In a more or less near future, it would not be surprising to see them listed by the CITES. Their range in the wild only covers 1600 km² (600 square miles so about one-fifth of the Rhode Island territory!) and they are found from 150 to 1000 meters above sea level (450 to 3000 ft.). The latter information also explains why temperatures in their microhabitats are not so high, along with a high evaporation level and shady environment.
Lifespan: 15-20 years, 22 years in some specimens, so think you will have to ensure the well-being of your crested gecko for that amount of time!
Description: a stocky gecko, with a triangular head, and spiny, well-marked scales along the head side and two similar rows continuing on the whole length of the body. Adult length of wild specimens is up to 250 mm (10”) but in captivity, sizes around 20cm/8” are more the norm. The tail is prehensile and can be easily dropped and will not regrow! Hatchlings are usually 0.2 gramms at birth and 50 to 55 mm long including tail (2”). There can be black spots on them, the normal coloration varies from beige to dull brown.
Sexual dimorphism: adult males have very well-marked bulges at the base of their tails. At an earlier age, two or more rows of preanal pores can be seen with a magnifying glass-these are scales with a tiny spot in the middle, only found in males. Such pores can be noticed as early as 2-3 months after birth, but it might take longer with some individuals. Males are very aggressive and territorial towards each other, never house two of them together!
Morphs: a lot of morphs are readily available on the pet trade, among which: pinstripe (two clear parallel lines all along the back), orange, yellow individuals…
I will strongly advise to be extremely cautious with the high level of inbreeding. Most morphs are recessive traits, so breeding them together to obtain morphed individuals implies a selection on a very reduced (see above) gene pool. This is likely to cause deformations, not only at birth but after several months, with a high rate of mortality before these geckos reach their first year. Recessive traits are not only attractive, colorful mutations but they also imply invisible changes, possibly affecting the internal organs and metabolism of these geckos. Since it is no longer possible to obtain wild new lineages, the problem is likely to be more and more visible within the next years. I have seen some wild specimens, their size and bulk alone is not comparable to crested geckos produced after several captive generations!
Housing requirements
Some keepers assume the larger the enclosure, the better. In my own experience,
1) Do NOT house more than 3 adult females with a male together.
2) Too large enclosures are likely to make prey-spotting more difficult for crested geckos. They are quite clumsy for an arboreal species, and not so fast-moving.

Thus, a pair or a trio can be comfortably kept in a 45x45x60 enclosure (18”x18”x24”). They really don’t need more space, and it does correspond to their actual territory in the wild.
ExoTerra terrariums are fine for them, as well as waterproof homemade enclosures, or simple glass enclosures. Juveniles (below 12 cm/6”) need to be housed INDIVIDUALLY in 25x25x40 (10”x10”x16”) tanks. Remember they are fairly cannibalistic and will not hesitate to attack another crested gecko nearly their size!
Heating and lighting
NEVER let temperatures go beyond 83°F with crested geckos. If you can’t provide such temperatures all year long, f.e. if your house will be overheated in summer, better choose another species.
They need 12 hours of lighting and heating all year long. During the night, all lighting and heating aggregates are simply turned off, for example through a timer plug. Night temps can safely reach the low 60s/ 16 to 20°C. Day temps should be between 20 and 27°C (68-81°F) with an optimal range of 22-25°C (72 to 77°F).
Fluorescent tubes can be useful if you grow live plants inside their enclosure; choose f.e. Sylvania tubes for tropical aquariums plants, otherwise these geckos are mainly nocturnal and do not need any UVBs. Only animals with a proven deficiency (MBD) should be exposed to 5% UVB (5.0) neon lights such as Zoomed’s fluorescent tubes.
Otherwise, depending on the tank size and room temperature, a 25 watts (or 40 if your reptile room is really cool) normal bulb is sufficient to reach the proper temperature. Contrary to snake owners, you will not have to protect the bulb as the geckos will naturally keep away from them. Colored bulbs are a good option since these geckos do not particularly appreciate very bright lights.
Setup
I recommend covering the inside back wall and the sides with cork bark oak panels: geckos will feel safer in such a “closed” space and this will help reduce their stress level.
As for the substrate, it needs to be slightly moist but in no way soaked and swampy (this would cause fast mould growing). DO NOT USE CLAY BALLS as it could damage the eggs while you are looking for them. To me, a layer of vermiculite or perlite is not a good idea as it may be digged up by geckos and swallowed, thus causing impaction.
Sterilized garden earth or coconut mould are the best substrates for adult crested geckos (it is recommended to keep juveniles on paper towels until the age of at least 3 months). A layer of 7-10 cm will do (3”-4”), which you can cover with dry dead leaves for a more naturalistic effect.
These geckos are arboreal so they will need some stout branches. Bamboos are too smooth for them. Choose fruit tree branches and NEVER use cedar-based, pine-based or willow-based products as they are toxic to geckos. Place branches vertically and horizontally as perches. Use shelters such as vertical pieces of cork bark oak, emptied coconuts…hides are of utmost importance for their well-being!
Plants such as bromeliads, tropical ferns, ficus pumila can be safely used and will give your setup a natural look. Do NOT use stones and/or sticky or edgy materials in your setup, as these geckos jump with great strength and may injure themselves. You can look at enclosures made for poison-arrow frogs to build your own natural planted setup. Note that coconut mould does not help plants t grow, you may have to use a layer of sterilized earth then, and earthworms will do no harm.
Water and drinking
I would not recommend as much humidity as many keepers mention. I have kept for example pairs who were never sprayed without any issue. The precise environment in which crested geckos live is not so humid. Neither would I think a small fountain will help –it would more likely cause injuries if it has sharp edges, and will also cause prey insects to drown inside it and mould. Likewise, hygrometers tend to stress out more the keeper than the geckos themselves!

For these reasons, I recommend:
1) A shallow water dish in each enclosure
2) That the substrate is kept constantly SLIGHTLY moist
3) Light sprayings every evening; no need for a misting system, no need neither to worry if you are away from home and can’t spray enclosures for a few days!
Feeding:
Hatchlings can be fed every other day after their first shed, which occurs approx. 48 hours after hatching from the egg or even before that. Adults will need to be fed twice a week.
I go for an “all-natural” diet: properly gutloaded crickets as a staple diet. Several species of crickets can be used. Mealworms, superworms, waxmoth larvae are to be strictly avoided. Locusts are generally ignored. Some roach species such as B. lateralis (“red runners”) or small dubia roaches work well too. Silkworms are also particularly interesting. Do not dust prey insects before the geckos reach 3 months old, this may cause major metabolic issues. Feeding should occur in the evening, once the enclosure has been misted and that the lights are off inside it.
Otherwise, dust prey insects with Calcium+D3 (NO PHOSPHORE!) on every feeding. I use Miner-All I and once a month, a multivitamin powder (Korvimin ZT or Nekton Rep). Avoid supplements containing phosphore such as reptivite.
Once a week, offer your geckos some fruit baby food or even smashed fruits such as bananas, peaches, papayas, mangos, all of them are readily eaten and rich in calcium. Bee pollen and liquid honey are also readily consumed. There are individual preferences though, some specimens will tend to eat more fruit or honey while others will almost always stick to insects. Keep in mind fruit is far less rich in proteins than insects, so that insects should always be fed as a priority to ensure the normal growth of your geckos.
I will NOT recommend CGD as a staple diet. It may be useful at times when no live insects are available. I have many reasons to say so, including the lack of variety of nutrients for such an omnivorous species, the risk to see the geckos getting weary of that diet on the long run, and we do not have any valid scientific study on the long run for geckos whose lifespan may exceed 20 years old! It has also been shown many times than a CGD-only diet causes the adults to be slightly smaller and lighter than those fed more traditionally with insects and fruit. The CGD can be handy, I agree, though it is comparable to feeding a pet ferret with fresh meat or with pet store pellets, there is a HUGE difference in terms of health on the long run.
Breeding
These geckos breed readily, without any brumation period. If you want to simulate natural conditions, a cooler and drier period over 6 months will succeed to a slightly warmer and more humid period. They are sexually mature at one year old but I would in no way advise to breed them before they reach 18 months. Males are prone to hemipene prolapses when they are too young, and females stop growing from the moment they produce their first clutch. I base myself on age and on the health of breeding specimens, not on weight.
Clutches of two eggs (exceptionally one at the beginning, usually infertile) are buried into the substrate and you will have to look carefully to find them. I once found 18 eggs in less than 4”x”4”x4”! They are oblong-shaped and hard-shelled.
Incubation is better with a night time temperature drop to 20°C (±75°F). I incubate the eggs in a 50/50 mix of coconut mould and perlite, the eggs are completely covered by the substrate and kept inside cricket plastic boxes with tiny air holes. The substrate should never be dry, nor damp. When it just begins to stick to your finger then that is perfect. Extreme temperatures (20°C/75°F and 30-31°C/85°F) tend to produce more females than males. Such temperatures are also likely to cause incubation issues. Around 26°C (80°F) there seems to be a balanced male/female ratio from my own records over a lot of hatchlings. With high temperatures, eggs may take as little as 42 days to hatch, while at low ones, 65-75 days are not uncommon. You can possibly house several youngs of the same age until they reach 6 months of age in the same enclosure, just make sure every specimen gets a correct food intake and that there are no noticeable size/bulk difference.
General advice for beginners:

1) Read more than one care sheet to make your own opinion.
2) Juveniles are much more fragile than adults, so you should start with an adult crested gecko.
3) Make sure you have a good reptile vet near your place and keep money if ever you need to see a vet.
4) Handle them as unfrequently as possible. They do not particularly like to be handled. They are not suitable for kids under 10 years of age at least. Unnecessary handling will provoke stress.
5) Never grab them, just leave them gently moving on your hand. Remember tails drop easily and don’t regrow.
6) Make sure people in the house will tolerate live insects (even if kept inside a box). Properly gutload prey insects at least 24 hours prior to feeding them to your geckos. Make sure you have a choice of insect suppliers either through pet shops or through the Internet (this solution is usually cheaper when you have several geckos).
7) Never let your crested gecko wander in a room without your presence and keep away all other pets.
For health issues (MBD, floppy tail syndrome…) and more precise questions, post in the appropriate section of this forum.
9) If you want to breed them, remember the market is now saturated with offers so that “normal” crested geckos will only go for a very low price. Don’t expect to make money with them!
10) Be aware such a species, with the inbreeding issues described above, could cause some new keepers to be upset. In that case, choose another species which is maybe less popular but without these massive genetic issues.
11) Do NOT think as crested geckos are always Captive-Bred, they may not host internal parasites. Dirty cages or poor husbandry, or again mixing them with other species may cause such issues.

Suggested readings:
-BAUER, A.M., Jackman, T.A., Sadlier, R.A., Whitaker, A.H. (2012) "Revision of the giant geckos of New Caledonia (Reptilia: Diplodactylidae: Rhacodactylus)". Zootaxa 3404: 1 – 52
-BARTLETT R. D., Crested Geckos and Relatives, Facts & Advice on Care and Breeding, Reptile and amphibian keeper’s guides, Barron’s Publ., New York, USA, 2004, 46 pp.
-BARTLETT R. D. & BARTLETT P. P., Geckos, A Complete Pet Owner’s Manual, Barron’s Publ., New York, USA, 1995, 105 pp.
-BERGMAN J., Geckos: day geckos, tokay geckos plus New Caledonian geckos and more!, The Herpetocultural Library, Advanced Vivarium Systems, Irvine, CA, USA, 2006, 160 pp.
-BLACK A., Crested geckos ,a complete guide to Rhacodactylus, TFH Publ. ,Neptune City, NJ, USA, 2005, 128 pp.
-DE VOSJOLI P., Crested Geckos, The Herpetocultural Library, Advanced Vivarium Systems, Irvine, CA, USA, 2005, 92 pp.
-Pr. HENKEL F. W.,Pr. SCHMIDT W., Geckoes ,Krieger Publ., Malabar, FL, USA, 1995 ,237 pp.
-Pr. SEIPP R. & Dr. HENKEL F. W., Rhacodactylus :Biology ,Natural History & Husbandry, Chimaira Ed., Frankfurt am Main, 2000, 174 pp.
-SEUFER H., Keeping and Breeding Geckos, TFH Ed., Neptune City, NJ, USA, 1995 (réédition de 1991), 192 pp.
-WALLS J. G. & WALLS M., Geckos: Keeping & Breeding them in Captivity, TFH ED., Neptune City, 2nd ed. 1998, 64 pp.
Hervé SAINT DIZIER, Thorr Geckos, for Geckos Unlimited, Dec. 2012