Tsd

[Katatonic]

Temperature Sex Determination is crested geckos:

It would seem there is a bit of debate among keepers of Rhacodactylus ciliatus. What would the majority vote be on whether crested gecko sex is determined by their incubation temperature?? Is it, or is it not true, and WHAT source did you derive your final decision from??

Personally, I've found three sources. All conflicting. Ideas anyone??

[Youkai]

I have done incubating as per the Rhacodactylus book published by Seipp and Henkel. At best I seem to get a 40:60 ratio of males to females. Certainly not an extreme ratio of females like they claim. My temps are bang on.
I know others who have followed the method in the book and get the same results as me. I don't want to put my foot in my mouth here, but I'd be inclined to say the incubation temps for R. ciliatus in that book are not correct. I have not heard of ANYONE having success with it to get mostly females.
I think they are TSD. Probably involves temperature swings among other things, however. Personally, I'd like to know what kind of ratio of males to females are found on the islands themselves...

[Katatonic]

Cheers. I'm for that idea as well... It would be more than interesting to figure out how many males there are naturally occurring. I'd care to wager that there wouldn't be a massive accumulation of males out there, as is seen in the pet trade!! lol
I as well am beginning to think that there are alternate factors in temperature sex determination in ciliatus. It's gotta have to do w/ daytime highs or some other form of flux.
LATER!!

[Mike177]

maby you should try doing a little experament yourself? it could be fun. :D

[Kyle Barker]

A buddy of mine is experimenting with this in small numbers. Last year he incubated everything fairly high (84f), and every single one turned out to be male. this year he is trying all diff temps, some as low as 62, and the highest at 78. When he grows them up i will let you know what everything turns out to be.