Number of Eggs Per Clutch

[webskipper]

Pertaining to Greeks (Ibera) what is the average number of:

1) Eggs per clutch

2) Clutches annually

3) Hatches per clutch

4) Successful hatchlings @6 months or when sold.

I ask about the success rates because it sounds like most hatchling are sold are around 6 months old.

 

[egyptiandan]

Lots of variables here

Average clutch size depends on the size, age of the female and genetics.
I have a 10 inch female that averages 6 large eggs per clutch. I have a 9.5 inch female (not perfectly grown) that averages 2.5 large eggs per clutch. If you know what mom's average was than you'd get a good idea of what the daughters would be.

Clutches annually depends of mom's nutrition and genetics. My females average 3 to 4 clutches a year.

Breaking this one up Fertility rate would depend on the females age and the compatability of the male. About half of first time clutches are infertile. If the male isn't compatable, than the fertility rate will be down.
I'm getting a 100% fertility rate.
Hatching rate depends on incubation and genetics of the egg. Hatch rate should average around 90% or higher.

The last question depends on what you provide for nutrition and the genetics of the hatchling. I'm up around 99%.

Danny

 

[GBtortoises]

I agree with what Danny has stated above and would also like to add:

Younger, smaller females often lay smaller eggs and less of them per clutch. As they grow to full adult size they're clutch size and even egg size increase. Not only with Ibera but other Northern Mediterraneans. I have Marginateds and Ibera that I've raised from either hatchlings or young that are now adults and many began with 1 to 3 small eggs per clutch. They (the females) were smaller themselves. Now as adults they are laying 4-8 eggs per clutch, depending upon species. The Ibera eggs in particular are huge compared to other Mediterranean species.

I don't totally agree that genetics determines the number of clutches. Environmental conditions have a lot to do with it too. Mine are kept outdoors from April through October which is when they breed. When we have a particularly cool and wet summer as we did this past summer here where I live my tortoise don't lay as many clutches. This past summer was one of the worst I've had in terms of them laying eggs. The fertility rate was high but the number of clutches was much, much lower. But when they were brought indoors where it was more consistenly warm and dryer they began mating and producing eggs!

I have never had any problems with hatchling or young tortoise mortality. I've never, that I can recall, had a weak one that didn't make it. I actually prefer sell all the hatchlings as soon as I can because I believe in getting them into their new environments and acclimated when they're young so that they don't have to readjust when they're older. I keep them a minimum of 10 days to ensure that they're eating, drinking and there are no other problems. After that they can go at anytime.

 

[webskipper]

Makes a lot of sense. Thanks for the information. I had a long conversation with a long time breeder this weekend that pretty much confirmed the same.