TSD Experiment...Opinions?

[Adrn]

TSD - Temperature-induced Sex Determination...

I am attempting to see if I can produce some males from a laticauda laticauda clutch that my female just laid yesterday. They were laid into oviposition on a split piece of bamboo directly under the halogen puck light. From some breeders I have spoken with in the past, it is believed that a greater ratio of males come from phelsuma hatches that take place insitu. I believe this may have something to do with the high temps where they were laid and the temp swing down ~8-10 degrees F at night. I have marked the clutch to keep them positioned as they originally were. What I plan to do is leave the clutch exactly where it is as long as I can, up until my pair #1 female gets ready to lay her next clutch. Based on her last clutch laid before this one at 22 days, I am figuring the duration will be close to the same.
Let me know what any of you think or have experienced through your own breeding programs.

-Adrian

 

[Ingo]

Keep them at constantly 30°C for the first three weeks and then allow lower temps and a night drop. That should give you a high percentage of males. At least in grandis this results in ~90% males.


Ingo

 

[DavidK]

Adrian,

This species does not seem to require dynamic modulation of the temperature regime to produce males. I have produced several generations of Phelsuma laticauda laticauda at home and found:

1. At a constant 81-82F in an incubator, I get roughly 1:2 to 2:3 ratios of males to females.

2. At a constant 87F, I get an approximately 6:1 ratio of males to females.

I have tried to incubate at room temperature (approximately 70F - 75F) with no supplemental heating to see if I get all females, and have had a fairly poor hatch rate.

Regards,

Dave

 

[Adrn]

Dave/Ingo,

Thanks for the replies. I was more trying to replicate a natural temp swing based on the OP of the clutch being directly under the halogen puck light during the day and then lights out with the ambient temps of the room overnight. However, over the last two days I have noticed the clutch has been moved around in that spot. Probably due to it being a high traffic basking spot. I reached in this morning and positioned it up against a bamboo section to see if this would help keep it from shifting. I think I may prematurely remove the clutch and transfer it to the incubator for the sake of the clutch if I see any more shifting.
Thanks for the detailed responses.

-Adrian

 

[Adrn]

...So I decided to remove the clutch and put it in the incubation chamber. I came home from work and went to spray down the tanks when I saw that the clutch had been shifted again. I will try again with insitu hatching if any of my breeder pairs' females decide to lay in the sansevieria.

-Adrian