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Problem solver

This year I hatched eggs outside with no substrate! I had three Eastern Yellowbellied Racer females wild caught all gravid. I had a cage with an underground sump. Two of the females laid eggs at the bottom of the sump and one female laid eggs under the flowerpot covering the sump but not in the sump. All of the eggs were left where they were laid. Most of the eggs in the sump hatched with no substrate whatsoever and all of the eggs on the ground under the flowerpot hatched! We are talking about temperature over 100F and as low as 62F at night! No Substrate. I will get some pictures as the slit eggs are still there in the cage. A friend of Maxes found Greri eggs between two boulders in the desert and……………..yes………..They hatched also! My question to all is how can this be?
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"Life without risk is to merely exist."

The experiment was a raging success but my guess would have been 100% success in the sump and complete failure under the flower pot. Here was my reasoning. It was cool inside the sump. What happens to a can of beer inside of a fridge when you open the door to the fridge the can condensates moisture in the outside of the can. The sump was cool therefore attracting moisture but I failed to put any substrate into the bottom of the sump so the eggs at the very bottom were sitting on a wet surface. The sump was 3 inches in diameter so the eggs were stacked on top of each other. A few of the eggs on the bottom rotted but most survived and all of the upper layer hatched. The flowerpot had a side hole cut into it but the bottom hole now on top I plugged to keep rain out of the sump. The floor of the cage was chunk coconut which evidently held enough moisture to successfully supply eggs with moisture. I examined a handful of hatchlings and found no kinks. If you take this experiment for face value what do you learn?

2 of the three snakes preferred the sump
1 snake preferred the ground under upside-down flower pot
1 clutch of eggs had radical temperature & moisture fluctuations and all hatched
2 clutches of eggs had a more stable environment moisture & temperature some failed
Wet surface likely culprit for failure but?
These Snakes had access to Natural Sun when gravid and all had a Wild Diet
2 of the snakes shared a nest 1 did not
None of the females cannibalized each other or bothered the others eggs

Questions to ask yourself

Does fluctuating temperature help or hinder quality of snake eggs?
Does fluctuating moisture help or hinder quality of snake eggs?
Does diet affect quality of snake eggs?
Does natural sun affect quality of snake eggs?
Does the temperature a female gestates at affect quality of snake eggs?
Which questions can we cancel out with the above model?
Which factors am I not seeing?
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"Life without risk is to merely exist."

Sounds to me like you are documenting the natural robustness of the ophidian reproductive biology in a natural environment.

My gut feeling is that captive husbandry is dominated by the idea that the slightest mistake will be disasterous. In nature, wild temperature fluctuations and moisture swings may be the rule rather than the exception.

Could it be that these animals are a lot tougher than we give them credit for?

John
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I am so not lesdysxic!

0.1 Creamsicle Cornsake "Yolanda"
1.0 Bairds Ratsnake "Steely Dan"
0.1 Desert Kingsnake "FATTY"
0.1 Black Rat "Roberta" RELEASED!!!

Yes so far it seems that our domestic animals are handycaped when it comes to reproduction. It seems that some snakes are resistant to captive conditiond and other need sun, more vitamins or something. I think I know what that something is but a few more years of research should nail it down.

Here are a few more things to ponder.

The male snakes are absent from the equation
The flower pot was clay and had a large entry hole in the side so moisture dissipated quick
Snake eggs that were laid in cleft of desert boulders had little or no moisture
The eggs found in cleft of boulders piped within a day of discovery!

We assume our eggs that start good and go bad had some problem with incubation but what if you turn the equation on its head? Is it possible that the egg had problems not laying down enough calcium or other vitamins that formed a weak membrane? Could the internal structure of the egg been hindered in some way? Are your slugs , slugs because the male was infertile or were the eggs doomed from the start? Could they actually be fertile but to weak of a membrane or shell to support life? I think the answer falls on both sides of the fence. Substrate in and of itself is problematic as is the water we use to moisten it. Substrate and water alike have differing pH levels not to mention contaminants.

I will extend a challenge to Robert (Vitamins vs. Sun)
So far you use vitamins instead of sun (for the most part) You send a female that lays infertile eggs and a male proven to shoot blanks and we will be one step closer to the truth . I have no interest in keeping the animals I am interested in the science.
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"Life without risk is to merely exist."

i dare ask, did you measure the humidity in these spots or were you only looking for liquid water? with temperature fluctuations between day and night in a clay pot and between rocks there might be enough water vapors due to condensation to sustain an egg or three. Again many egg deaths during captive incubation occur because of too much water. I don't believe liquid water won't cross an eggshell easily until it builds up enough of a gradient, otherwise it sits outside and reduces gas exchange and smothers an egg.
i am really interested in the avey incubators and the method of substrate free incubation some use for gtp's. one of these days I will get the cujones to try it with some eggs. As an aside, I don't think that gtp's or burms for that matter are controlling the temps, within their coils. for goodness sakes, they are in the tropics. I would bet that the effort is to control water and gas exchange, just as what would involuntarily happen to a clutch of eggs surrounded by soil or decaying organic matter. (Yes I guess if you change the temps, you change the properties of gases, but Ithink the main purpose of coiling is to control gases.)

my .02 at 2256 EST...thanks,
daveb

I do believe liquid water won't cross an eggshell easily until it builds up enough of a gradient(then swells an egg); otherwise it sits outside and reduces gas exchange and smothers an egg.

>>my .02 at 2256 EST...thanks,
>>daveb

I WOULD AGREE THAT TOO MUCH WATER IS THE CULPRATE IN MOST CASES. IN KANSAS THE HUMIDITY HOVERS AROUND 60% IN JUNE BUT THERE ARE SPIKES IN BOTH DIRECTIONS. THE EGGS IN THE DESERT BETWEEN TWO BOULDERS SHOULD HAVE DESICATED. THE CHALLENGE IS TO FIND OUT WHY THEY DID NOT. LIKEWISE THE EGGS UNDER AN UPSIDEDOWN FLOWERPOT ALSO SHOULD HAVE DESICATED SINCE THERE WAS A LARGE HOLE IN THE SIDE. YOU HAVE TO START WITH WHAT YOU KNOW. GECKOS HAVE A HARDER SHELL THAN MOST LIZARDS AND THEY GLUE THEM TO WALLS. GECKO EGGS HATCH IN THESE CONDITIONS SO THAT IS A STARTING POINT. IF WO GO FROM THERE WE MIGHT CONCLUDE THAT A SNAKE MIGHT BE ABLE TO REGULATE THE AMOUNT OF CALCIUM LAID DOWN ON AN EGG? HARDER EGG LESS FRAGILE TO EXTERNAL CONDITIONS. IF WE ADD TURTLE EGGS TO THE MIX WE MIGHT ALSO REALIZE THEY ARE BURRIED AND GET DRENCHED WITH WATER IN RAINSTORMS IN THE WILD AND……….HATCH. TURTLE EGGS ARE HARDER THAN SNAKE EGGS FOR THE MOST PART. HARDER EGGS HIGHER HATCH RATE? HOW DO YOU MAKE A SNAKE EGG HARDER? MORE ABSORBABLE CALCIUM?
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"Life without risk is to merely exist."

well, turtle eggs are much harder [& tougher] to hatch than snake eggs, that's for sure. they have a more bird like texture to them. starting this year, i'll no longer unearth & bring in the eggs i see my turtles laying outside. but as far as them getting drenched, i don't know about that as they're laid in a vase shaped chamber which i believe allows water to go around them. re: substrate, i've tried everything thru the years but in recent summers i've gone to damp towels w/ a cup of water on the side to help keep up humidity. this did seem to help the success rate some but overall, turtle eggs are a pia so outside they'll stay where they were laid. besides it's kinda cool when i start finding the little guys wandering around later in the summer.......

My box turtles lay eggs in sand. If the chamber is vase shaped it has no shape when finished! LOL
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"Life without risk is to merely exist."

i used to put sand out back but the cats thought it was for them. end of that method! but yes, in dirt the egg chamber is actually vase shaped or picture an upside down Y & it can take them hours to laboriously dig out. i keep both aquatic turtles & tortoises & they all employ the same tatic & usually laying in the same spots year after year. but if your boxies lay in sand then their eggs would remain dry also, correct?

My box turtles laid in the sand year before last. I dug the eggs up after a huge rain storm. The sand was soaked. I got 9 eggs from two females and all hatched. I assume wild eggs of lizards, snakes and turtles perodicaly become wet and hatch whereas captive eggs just seem to die from standing water. I already have some data that supports the theory but more work is needed. I will be artifitaly hybernating eggs this year also. I almost pulled it off a few years ago but.... yes they got too wet. They stayed alive for about five months at 55F. They were Trans Pecos Ratsnake eggs. Max was the brainchild on that expiriment.
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"Life without risk is to merely exist."

Sighthunter -

Clean sand has very high conductivity and transmissivity - it doesn't hold onto water like silt or clay. Water percolates quickly through sand, so it doesn't stay saturated. Also, sand in the vadose zone (the areated zone) retains pockets of air (bubbles) which provide oxygen. The only place sand will be permanently saturated with liquid water with no intersitial air is below the top of the local water table.

So when a storm dumps inches of water, the eggs are not drowned for two reasons. 1st - the water drains away quickly; and, 2nd - the sand holds pockets of air. This is why eggs buried in sand can survive storm events.

The only time eggs laid in sand will drown is if the water table rises to cover them. In a natural setting, this is unlikely unless the water table is close to the ground surface to start with.

Sand also retains water due to capillary action between the grains. Sand may be perfectly dry on the surface, but have ample moisture an inch below. This moisture sink prevents eggs from drying out and also moderates temperature extreams by evaporative cooling.

What kind of rock was that? Some types of rock, like sandstone, have high porosity and conductivity, which alows tham to act as moisture sinks and temperature moderators like sand.

I believe this is what was going on with your flower pot. That type of pottery is porous and retains moisture well. It could have acted as a moisture sink and temperature moderator to allow those eggs to survive the extreams of dryness and heat.

Try an experiment if you like...soak that flower pot in water, now put one temperature probe under the flower pot and one on top, then set it in the sun. You could also use a humidity probe if you can rig one up.

John DeMelas
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I am so not lesdysxic!

0.1 Creamsicle Cornsake "Yolanda"
1.0 Bairds Ratsnake "Steely Dan"
0.1 Desert Kingsnake "FATTY"
0.1 Black Rat "Roberta" RELEASED!!!

These eggs have been outside now for about one year. Notice that the flowerpot in no way trapped moisture and the substrate made almost no contact with eggs yet all hatched. 100F plus temps and all. The quality of the egg shell to resist deteriation after being left outside for a year speeks for itself.

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"Life without risk is to merely exist."