Day 32. Fertile perhaps?

[Kirkie]

That would depend. If you incubated at the normally recommended 31-32C those that did hatch would be female I'd assume. You might have a poor hatch rate at those temperatures though. Danny said he gets a mix of male and female at 28-29C, most people I know who breed Herc's (not many) use 29-30C but its too soon to tell if this swings it in favour of females. Thats why I risked nearly 31C for a period, to see if I can get some girls without risking the higher temperature throughout.

I'd love to know why this is the case, I've incubated Boettgeri fine at 32.5C (though I do now drop that to 31C after 4 weeks) and Hercegovinensis don't live a million miles away from Boettgeri, in fact they co habit some areas. Maybe they choose different nest sites or dig deeper nests.

[shellshock]

Originally Posted by Kirkie

Yes, you are correct. In Hermanns tortoises higher incubation temperatures should produce females. It's the duration of that higher temperature that I'm interested in. It's been proven that the sex is determined in the first half (possibly the frist third) of incubation so, in theory, the temperature after the first half should have no affect on the sex of the resulting hatchling.
It's been proven that as few as seven days at female temperatures in the first 37 days (I think) but after the first seven days of incubation will produce females. To incubate male Hermanns (these ar eBoettgeri I'm talking about) a longer time at "male" temperatures is required to fix the sex.
These eggs are from a Dalmation Tortoise (T.Hermanni Hercegovinensis) and the eggs seem to be more sucessful if the temperatures are kept lower. Without knowing the temperature at which more females are produced than males its difficult to incubate for females because all the normally receommended "female" temperatures for female Hermanns are too high for Hercegovinensis and could result in the losss of the embryo if those temperatures were used throughout the incubation.
So I'm trying to use an initial temperature to determine the sex and then a lower temperature to (hopefully) ensure a sucessful incubation.


On your last point, there is no guarentee that I know the sex of the already hatched hatchlings. There are a couple of physical characteristics that give me a pretty good idea of what they are though.

thanks for that , my girl laid three eggs and only two hatched successfully the other one all though fully formed failed to hatch, they are T. Hercegovinensis so perhaps the temperature was to blame I will remember this for the next clutch next year. ( hopefully)