research paper about using different temps to get different ratios of male vs. female

[teresaf]

I found this a few years ago and thought it was very interesting. We need more females than males so if we educate more of the hobby breeders perhaps it won't be as difficult to find those females we all need for our groups/herds some day in the future. I REALLY found it interesting how these folks managed to get 100% females. REALLY, how often do we need a male bred? Females are in greater demand...Maybe someday when we order a male and female (or rather 2 or 3 females) hatchlings we'll ACTUALLY get what we want...

http://scholarworks.gsu.edu/cgi/viewcontent.cgi?article=1010&context=biology_theses

 

[JoesMum]

Temperature control to breed for gender has been mentioned on here quite a bit. Usually by newbies who have bought a female tortoise hatchling and then we sex it as a male.

The temperature is true. Getting it right is very difficult. Catching the clutch being laid at exactly the right time, having an incubator that is exactly at the temperature required without variation, etc is not easy.

I guess some breeders may get good at it, but given the length of time required to be certain I guess that most will not worry too much when a percentage fails to be the desired gender years down the line.

 

[teresaf]

Temperature control to breed for gender has been mentioned on here quite a bit. Usually by newbies who have bought a female tortoise hatchling and then we sex it as a male.

The temperature is true. Getting it right is very difficult. Catching the clutch being laid at exactly the right time, having an incubator that is exactly at the temperature required without variation, etc is not easy.

I guess some breeders may get good at it, but given the length of time required to be certain I guess that most will not worry too much when a percentage fails to be the desired gender years down the line.

I doubt breeders worry too much about it now since they wouldn't get feedback(complaints) until years later, IF the tortoise lived, IF the owner remembers who they bought from, IF the tortoises were able to be traced back to a specific breeder in the first place. I just thought it would be nice to have the info out there as something to strive for, you know?

 

[Crzt4torts]

My Russian pair has had several clutches of eggs. I was aware of temperature related sex determination, and have aimed for females. My 3 successful hatches are only 15 months old...so I am still waiting to see the outcome of my attempts.
I do see 2 of the 3 babies clearly larger (size and weight) than the third, any experience with growth variations at such young age and sex? At adulthood female Russians larger than male...I am hoping maybe my 2 larger babies may be female (?) but no idea if sex related size difference translates in such young ones.