Last year my eldest son received his dream pet - a New Caledonian Giant Gecko (Rhacodactylus leachianus). The example I purchased was a 2.5 year old adult male and this year he wanted to pair them up. Cue another search for a decent female, which meant newly hatched examples were out of the question. It is only possible to accurately sex this species when they are between six - twelve months old. Even then you often require the help of a magnification device, in order to accurately view the presence or absence of pre-anal pores. These normally appear as black dots sitting in rows. The pores become more noticeable as the animal grows larger. Our adult male sports large, waxy, onyx examples that require no magnification. Couple this with a distinct hemipenal bulge and there is no doubt.
Females sometimes show pseudo pores, but often there is nothing at all. An example displaying no black markers removes uncertainty. Through persistent hunting and negotiating I was able to secure a sixteen month old sub-adult female (see pic above) at an excellent price. Definite females are scarce and command a premium, nonetheless private breeders occasionally have animals available.
The most frustrating part of purchasing a new Leachie is the time it takes them to acclimatise. New Caledonian Giant Geckos do not like being moved from their existing quarters and will normally hide away for days or weeks on end. Our female was no exception and it took the best part of three weeks before both our stress levels reduced and she ate a decent meal! The key is providing them with plenty of places to hide and cosy enclosures. In my experience this species does much better in smaller wooden vivariums that keep humidity high and reduce 360 degree visibility. People assume the world's largest extant gecko species must reside within large enclosures, but this is not the case.
Additionally the tank should not be too cool. Many people are of the opinion that it is ok to keep these animals at room temperature with no additional heating. That might work in hot countries but for the UK I simply do not agree. New Caledonia is warm and humid, it is not normal for these animals to spend most of the year at 17 - 19 degrees. They don't need to bask, being nocturnal, but are reptiles and require warmth to fire their metabolism. My experience suggests that an additional 5 watt heat source increases the temperature to safe levels that improve activity and digestion. You don't want it much higher than 27 degrees centigrade (although a maximum of 29 -30 is safe for short periods, assuming the air is humid and plenty of water available). Average temperatures in our enclosures are between 24 - 27 degrees. At the height of summer their night lights are turned off completely.
We constructed the tanks with our long term project in mind. NCGGs don't always pair successfully and it is not unusual for rejection to occur.
Last summer our male liked calling into the night, hopeful that a female would reply. No such luck! It will be interesting to see how Flossy, as we have named her, responds in the face of his clucking. She is not mature enough to breed, nowhere near, so I am guessing silence may be the preferred option. We shall see.
On a final note - previously satellite island examples were classified as R.l.henkeli. This distinction no longer exists and ALL examples are recognised as R. leachianus only. That is right, they are the same species.
There are variations between different locales but these are equivalent to people with brown hair and blonde hair - still the same species!
You will find examples marketed as Morro Island, Island E, Isle of Pines, Grand Terre etc... but there is absolutely no way you can be sure that these designations are correct. Most of the time people simply pass on what they were told at the time of sale. Some breeders were involved with collection of the original examples but even then can anyone be 100% certain that one of the grand parents or great grand parents were not from a different locale? It is simply a matter of trust. It is true that some locales are distinctive enough to suggest their original location, but what is to say that a cross wouldn't happen to show more of one ancestor's characteristics than another. This is basic genetics and it happens all the time.
It is true that the Grand Terre animals generally have relatively longer tails and are an overall larger size, but that in itself hardly proves the origins.
Many other species e.g. Green Tree pythons are in the same situation - examples being touted as originating from a variety of locales. Most sensible people now accept this as nonsense and a GTP is simply a GTP.
The point I am making is that unless you visit the island and collect examples yourself, then it is highly unlikely you can ever be sure of the purity. Especially now that science recognises all NCGGs as a single species! Don't fall for ignorance or marketing ploys and pay a premium.
Edit 30/03/16 - Success!! We now have four eggs in the incubator. The first clutch was laid 28/01/16 and the second around six weeks later. The female was starting to look thin, so we separated them again. Both continued to feed without issues as both sides are now considered common territory.