Diapause for South African Leopard Tortoise Eggs

[Turtle Herder]

My female SA leopard tortoise laid eggs last week. They are currently in the incubator at 88 F. I've heard and read that placing the eggs into a state of diapause often results in higher hatch rates. What I don't know is how long should I leave the eggs in the incubator before placing them in diapause. I've heard/read some people doing it immediately, before they go in the incubator or 30 days after going in the incubator. What I also don't know is what temperature I should keep them while in diapause. Some have said 40F, 50F and 60F. I know it's not likely an exact science and that any and all of the above methods may or may not yeild the best results. I'd like to know what methods others here have had success with (when, temp and how long). Thanks in advance.

 

[Tom]

My female SA leopard tortoise laid eggs last week. They are currently in the incubator at 88 F. I've heard and read that placing the eggs into a state of diapause often results in higher hatch rates. What I don't know is how long should I leave the eggs in the incubator before placing them in diapause. I've heard/read some people doing it immediately, before they go in the incubator or 30 days after going in the incubator. What I also don't know is what temperature I should keep them while in diapause. Some have said 40F, 50F and 60F. I know it's not likely an exact science and that any and all of the above methods may or may not yeild the best results. I'd like to know what methods others here have had success with (when, temp and how long). Thanks in advance.

First, do you have true SA leopards, or mixes?

If you have the real deal, get ready for years of frustration. My three females gave me about 180 eggs a year, and the best year ever saw a hatch rate of 10%. Most years I hatched 8-10. Don't have any idea why. The original breeder that brought this species to us from wild caught animals that he acquired directly form the importer in 1990 gave up trying to do it artificially. He simply left them in the ground here in SoCal, and ground hatched them. Then he had to race the local fauna to save as many hatchlings as he could from being eaten by birds, rodents, raccoons and other such animals. I tried all sorts of cooling temperature, durations and methods. Nothing worked well for me. Methods that gave other breeders 20-40% hatch rates did not work for me.

There is no point in having them in the incubator. They. will not develop with out the cooling period first. You may as well remove them now to room temp until you figure out how you want to cool them and for how long.

I wish you good luck. Experiment with different temps and time frames, and if you crack the code, please let us know. Questions are welcome.

 

[Turtle Herder]

Thank you for your reply, Tom! It is a pleasure to make your acquaintance. I appreciate the time, effort, insights and your willingness to share. My tortoises are pure S. p. pardalis, as far as I know (they all had the multiple spots in each scute as hatchlings). I got them from a very reputable breeder as hatchlings over 25 years ago. I successfully hatched 9 (out of 31) eggs total) last season without initiating diapause. Not great at math but that's just under 30% success. Some hatched sooner (at about the 5 month period, some went much longer). I just left the unhatched eggs in the incubator until they hatched (or went bad). Hoping to learn as much as I can to increase the ratio, if possible, but the whole idea of diapause kinda freaks me out as I don't want to do something to lower the ratio. I've currently had 8 eggs in the incubator (for about 6 weeks now) and my female just laid another 14 eggs last night which I excavated this morning. I'm not really sure what to do at this point: 1) start diapause immediately (before they go in the incubator), 2) put them in the incubator for 30-60 days or so then initiate diapause or 3) just put them in the incubator and leave them there until they hatch (which is what I did last season with some, but not great, success). I also still don't really know if I should diapause the eggs at room temp (which is generally about 78F in my house but may fluctuate a little) or put them in my little wine fridge (and if so, what temp to set them at). Researching diapause methodologies now, trying to decide exactly what to do. I've also attempted to candlelight the eggs to look for blood vessels and air pockets but have had difficulty seeing anything in the eggs. It would help if I really knew what those looked like. I've researched it as well and still don't quite know (with certainty) what I'm looking at. Anyhow, sorry for the long post. Just trying to figure it all out best I can.

 

[wellington]

I know nothing about diapause, just have an idea. With the eggs that were just laid, why not split them up and do the diapause on half of them and the other half straight to the incubator? You could also split them into three groups and put one group into the ground.

 

[Turtle Herder]

I know nothing about diapause, just have an idea. With the eggs that were just laid, why not split them up and do the diapause on half of them and the other half straight to the incubator? You could also split them into three groups and put one group into the gro

Thanks for the reply. I've actually considered trying exactly that (everything you mentioned). There might already be a clutch out there in the yard somewhere as I was gone for an extended period of time earlier this summer and she may have laid a clutch during my absence. There's no way to really know. I was hoping she would lay before I left, but she never did (as far as I know). If she layed while I was away, I should find babies about 2 months from now (Nov, which would be the 5 month mark). She laid a clutch about 3 weeks after my return and last season she laid multiple clutches about 6 weeks apart. The problem we/she has with laying in my yard is the soil is SO darn hard (nearly solid clay) and I've had to prep the nesting area that I put her in by softening the surface. She only has access to the nesting area when I place her in it. She had attempted to lay in a couple of other spots in the yard but always gives up after digging a little due to how difficult the soil is to excavate. If I can figure out a spot that I can place the eggs in some softer soils and where the babies would be confined and protected (from being excavated by the female when she lays again, from direct sunlight after they hatch and from any predators before/after they hatch), I will try that. If she laid while I was gone, it will be interesting to see if the babies can dig out of wherever that might have been. I will be surprised. If I decide to initiate diapause in my wine fridge, what temp do you think I should set them at (50F, 55F, 60F) and for how long (30 days, 45 days, 60 days)? Should I incubate them at 89F for 30-45 days, then initiate diapause? Should I candlelight the eggs and only diapause the eggs that don't have blood vessels or air pockets (or are the eggs that show the blood vessels/air pockets the eggs that I should diapause)? So many questions...

 

[wellington]

Thanks for the reply. I've actually considered trying exactly that (everything you mentioned). There might already be a clutch out there in the yard somewhere as I was gone for an extended period of time earlier this summer and she may have laid a clutch during my absence. There's no way to really know. I was hoping she would lay before I left, but she never did (as far as I know). If she layed while I was away, I should find babies about 2 months from now (Nov, which would be the 5 month mark). She laid a clutch about 3 weeks after my return and last season she laid multiple clutches about 6 weeks apart. The problem we/she has with laying in my yard is the soil is SO darn hard (nearly solid clay) and I've had to prep the nesting area that I put her in by softening the surface. She only has access to the nesting area when I place her in it. She had attempted to lay in a couple of other spots in the yard but always gives up after digging a little due to how difficult the soil is to excavate. If I can figure out a spot that I can place the eggs in some softer soils and where the babies would be confined and protected (from being excavated by the female when she lays again, from direct sunlight after they hatch and from any predators before/after they hatch), I will try that. If she laid while I was gone, it will be interesting to see if the babies can dig out of wherever that might have been. I will be surprised. If I decide to initiate diapause in my wine fridge, what temp do you think I should set them at (50F, 55F, 60F) and for how long (30 days, 45 days, 60 days)? Should I incubate them at 89F for 30-45 days, then initiate diapause? Should I candlelight the eggs and only diapause the eggs that don't have blood vessels or air pockets (or are the eggs that show the blood vessels/air pockets the eggs that I should diapause)? So many questions...

@Markw84 @Tom

 

[Tom]

Thanks for the reply. I've actually considered trying exactly that (everything you mentioned). There might already be a clutch out there in the yard somewhere as I was gone for an extended period of time earlier this summer and she may have laid a clutch during my absence. There's no way to really know. I was hoping she would lay before I left, but she never did (as far as I know). If she layed while I was away, I should find babies about 2 months from now (Nov, which would be the 5 month mark). She laid a clutch about 3 weeks after my return and last season she laid multiple clutches about 6 weeks apart. The problem we/she has with laying in my yard is the soil is SO darn hard (nearly solid clay) and I've had to prep the nesting area that I put her in by softening the surface. She only has access to the nesting area when I place her in it. She had attempted to lay in a couple of other spots in the yard but always gives up after digging a little due to how difficult the soil is to excavate. If I can figure out a spot that I can place the eggs in some softer soils and where the babies would be confined and protected (from being excavated by the female when she lays again, from direct sunlight after they hatch and from any predators before/after they hatch), I will try that. If she laid while I was gone, it will be interesting to see if the babies can dig out of wherever that might have been. I will be surprised. If I decide to initiate diapause in my wine fridge, what temp do you think I should set them at (50F, 55F, 60F) and for how long (30 days, 45 days, 60 days)? Should I incubate them at 89F for 30-45 days, then initiate diapause? Should I candlelight the eggs and only diapause the eggs that don't have blood vessels or air pockets (or are the eggs that show the blood vessels/air pockets the eggs that I should diapause)? So many questions...

I've tried every combination of things I can think of. Most of it simply didn't work for me.

Here is the main recipe I've seen people have success with, though it didn't work for me.
1. One week at room temp.
2. One month at 60-65.
3. One week at room temp.
4. Then incubate at 86-88. Should hatch in about 100-110 days.

I tried warmer, cooler, longer, shorter, and every variation I could think of.

 

[Turtle Herder]

Thank you for sharing that, Tom. Very kind of you. I truly appreciate it. Did you put them in the incubator before initiating diapause or did they do straight from the nest into diapause? Sounds like I'm gonna have to just start experimenting...