Reptile & Amphibian Forums

at what temps does every one incubate at and what is the average on days to hatch? Last year i incubated at around 83-85 and one clutch took 68 days to hatch. Any input would be apprecitated.
thank you,
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

80-82 on the temp, hatching after anywhere between 60 and 70 days. More often between 60 and 65 days to hatch.
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Mike

Thanks for the input, I am wanting to know what is the average male to female ratio? I have incubated gecko eggs at lower temps for more females and I know with alligators temps determine the sex and don't forget it also does with chickens. What do you think about snakes?
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

I know this doesn’t have much meaning, however at one point I did incubate two clutches at 84-85 degrees and the hatches were 2.6 and 2.9 which were thayeri and alterna respectively.

The subject of temperature dependent sex determination you’re curious about is an interesting one. As you already know, it’s understood that with some reptiles (crocodilians, most turtles, certain lizards…) hatchling sex determination is primarily environmental, meaning higher incubation temps produce a higher female to male ratio. A while back I dug in to a little research to see what I could come up with relating to sex development in kingsnakes. What I found was nothing conclusive, nothing that I found was specific to kingsnakes, however there does seem to be evidence that suggests higher temps can affect secondary sex determination in at least some egg laying snakes and produce more females. Secondary meaning during egg incubation and the latter stages of development. From what I understand, primary sex determination in most egg laying snakes is believed to be purely genetic… meaning that the sex of the embryo is determined genetically during the initial development while still being carried by the female.

Fairly recently I read a brief article (on livescience dot com) about a study done by the Australian National University concerning global warming and it’s potential effects on life, which was conducted using Bearded Dragons. What they determined was that in ideal incubation conditions for Beardies, an equal mix of male and females developed. When they raised the incubation temps to the higher end of the scale that would still allow the eggs to hatch, significantly more females resulted, indicating that the higher incubation temperature had over-ridden gene-controlled sex determination. They suggest that a gene on the Z chromosome triggers male development and a protein expressed by this gene is temperature sensitive. At high temps this protein becomes less effective and unable to trigger male testis development, and the Beardies develop instead as females with ovaries. The interesting thing about it was that when they analyzed DNA for both normal temp incubated lizards and high temp incubated ones, the phenotype of those incubated at normal temps matched their genetic makeup… males looked like males and females looked like females with regard to their sex organs. However, about half of the lizards from high-temperature incubators had a mismatched make-up, in which genetic males "looked like" females. Male on the inside (genetically), but phenotypically female.

Studies have also shown that egg-bearing snakes that are incubated at slightly lower temps (that take longer to emerge) hatch out longer from snout to vent, have better overall development and motor skills, improved brain development, can raise higher and hold back stronger to strike, and seem overall better suited for survival and being successful.

How much of this do you think could relate to our kingsnakes? Personally from all this I think taking a good middle-of-the-road approach to incubation temps is a good way to go, your decision to go with 80 degrees sounds great to me!

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Mike

Thank you for sharing that information on the beardies and the study. Made for a very interesting read. I am going to try the cooler temps, i like the fact of strong healthy babies, the longer wait will drive me nuts but I am patient.
I wonder with global warming what is going to be in store for reptiles such as turtles and crocdillians, since their eggs are determined by temps, will we see them go extinct? The big picture we are facing is bad, the polar bears are really starting to worry me, i would hate to only be able to see them in zoo's.
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

…that the possibility exists, particularly with certain species.

A good example would be the Nile crocodile populations in the Okavango Delta in Botswana. Durable animals and survivors for millions of years, however due to habitat loss and hunting pressure the crocodile populations there have dwindled severely and any additional setback could spell disaster. They need nest temperatures of 89.6 to 91.4 degrees to produce males… that‘s only a 1.8 degree window. Anything warmer or cooler produces females so you can see how little change in the environmental conditions could be critical. With less and less places to go to find a way, find the environmental conditions they need to remain successful, that population could eventually disappear.
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Mike

I incubate at exactly the same temps 83-85. I think mine might have gone to 86 or 87 once or twice too but mostly right around 84. My average last year was 59 days. I had one clutch that went 63.
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Vichris
"The object of life is not to be on the side of the majority but to escape finding oneself in the ranks of the insane"- Marcus Aurelius

Vichris Variables

first thanks for the input, now i want to ask a question did you notice a higher male to female ratio at these temps? the reason i am asking is i did have a higher ratio in the 1st clutch 7.5, but the second clutch the females were higher 2.5.
The mexican blacks were the same out of 8.2.
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

Hi Michelle

I use temps ~80, give or take a degree, and it takes about 65-70 days to hatch. What I've noticed in the past is that if I incubate at a higher temp range they do hatch faster but babies come out slightly smaller compared to animals that's incubated on lower temp range. Waiting a couple of days isn't so bad although it gets tough sometimes, hehe. Hope it helped.
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Jonel M. Lopez

www.spsnakes.com

same question what is the average on male to female ratio? Also thanks for the input.
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

Hi Michelle

As far as ratios go, the avarage is close to an even ratio with just a slight variation in different clutches on one side or the other. I have not seen any extreme male to female ratios with my thayeri clutches the past couple of years unless it is a really small clutch(i.e. 2-3 fertile eggs) which could go either way. Hope it helps a bit.
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Jonel M. Lopez

www.spsnakes.com

When incubating at 83-85 degrees do you any difference in male to female ratio?

I know in turtles/tortoises a higher incubation temp can result in a greater number of males, and inturn a lower temp results in a greater number of females.

I haven't really studied it much but I have a friend that for many years would incubate his eggs very low temps just on his shelves in Michagan.He had Honduran eggs that would go 90-100 days but they were monster size babies and almost all females.I remember he had a huge clutch of northern pines that hatched out 1.18 and a clutch of amel san diegos that hatched out 100% females.He claimed that the lowers temps determined the sex but it had to be allot lower or allot higher to really matter?

I use a average of 82-83 and most my eggs go 60-65 days and I usually get a pretty even split across the board on ratios.

Shannon

what temps was your friend using? When you say a lot lower or higher what range are we talking about? I am very interested to see if there is an influence with the snakes. I am going to incubate at around 80 this year to see what it does here.
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

he said most the times his eggs were low to mid 70s.I know he had several honduran clutches go over 100 days to hatch.
Shannon
p.s. I don't think that 80 is enough of a change to make a big difference.

He said it was in the low to mid 70s.I don't think that you using 80 will make any difference at all but a few more days of waiting.
I know he had several clutches go over 100 days.
Shannon

Do you think the a cooler temp (mid 70's) would effect fungus growing? I would think the cooler temp would slow it down.

Also I would think babies they staayed in the egg longer would absorb more of the yolk sack, and might not hatch out looking for a meal right away.

I would have thought all the eggs would have died at those temps, so this brings up the subject of I wonder how cold you can keep them and just prolong them hatching by cooler temps? I am not going to try but I wonder just how low there temps can acutually go before the egg dies? How cold do you reckon they get in the wild possibly down into the lower 60's?
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

I found this here on Kingsnake by Steven T. Osborne

http://www.kingsnake.com/colubrid/3.html

"The final and a most important aspect of incubation is temperature. For these three genera, a constant temperature of 74-82°F seems ideal. Temperatures over 87°F should be carefully avoided. Eggs incubated as low as 65-70°F will hatch successfully but take more time. Average hatching times for a few species at 80 degrees F are..."

So I would think low 70's should be safe. I have a few females due to lay this week. If I can catch the eggs before they stick to each other I am planning to separate a few and incubate them on the lower shelves of my rack. The ambient temp there hovers around 74, this way even if I lose them its not a whole clutch.

Thank you for the article and keep me informed of how things go for you at those temps.
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

All,

Once again the "Mexicana Forum" on KS.com comes through with assistance to a question...

Although it is going to be a while before I'll need that information for my Mexicana's...it's nice to have the "tips" in advance...

Later,
Jim.

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CSRAJim

well my experience is incubation temps in my snake room on the top shelf of one of my racks varies anywhere from 77-84 degrees. My results vary but I never have an unusally high number of males and generally have more females than males...which is a good thing. Everyone seems to want females
Good luck
Russ

Thanks for the info Russ, i have incubated gecko eggs in my snake room before but still have not gotten brave enough to do my thayeri yet. i may try one clutch that way this year. To see how much longer they take to hatch. Do you find they feed better and are generally bigger babies?
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Michelle
All things bright and beautiful,
All creatures great and small,
All things wise and wonderful:
The Lord God made them all.

yeah that is typically the case. I usually have less than 5% that are stubborn feeders. The clutches usually take 65-70 days to hatch.