Corn snake incubation

[Ryan]

I wanted to get some opinions from people who may have experience with incubating corn snake eggs, the general rule that I've always known is to incubate between 82-84F but recently I've been hearing and reading about people having some great success using a much lower temperature. The lowest I've heard has been 68F and apparently this produced a 100% hatch rate with larger than normal neonates, most other sources have mentioned basically room temp. between 70-80F with all cases reporting great hatch rates and 0 defects of any kind.

I'm going to do a couple tests on this theory myself as I will have 2 clutches this year with one already in the incubator, that one is going to be done at 82F which has always been the standard and the other will be done at approx. 75F. The second clutch I'm basically just going to leave in a container in the herp room which is heated to 75F with the odd fluctuation of +/- a couple of degrees. Just wondering if anyone else has heard or had experience in this area.

Thanks for any input,
Ryan.

[Tim Cranwill]

Those are some interesting theories, Ryan. I look forward to hearing about how this method works for you. I have always done mine at 83F and it has work fairly well for me. Maybe this year I'll try a couple different things with a few eggs too.

[Ryan]

I must admit I'm a little sceptical of the claims of successfull incubation at the lower ends of that range especially the 68F and I don't think I'd ever risk that but the 75-80F may be worth a shot. I've heard claims with other species of colubrid that these temps do have very high hatch rates as well as neonates that tend to be bigger and very healthy.........on the other hand the years of success with the 82-84F temp range is proven to produce good results as well.

[Ryan Wunsch]

Back in the late 80's when I had my first corns and wanted to try to breed them, most people suggested incubating the eggs at room temperature. I think part of it, was that overall, it probably got more hatchlings than the various "ghetto" methods that owners of a few pet corns would use to heat up their eggs. (Heat pad directly under the egg container (helva containers were suggested often I rememember)

A lot of people incubate colubrids in their reptile rooms (75 - 78), and I've always aimed low, rather than to aim high.

I think there is probably something to the larger hatchling size that comes with longer incubation times at lower temps, and I've heard a lot of people speculate that it also makes for baby snakes with better temperments.

Since using temps around 77 F for colubrids, (as apposed to 82 ish like i used to) - I've found that the babies seem to feed better, and are less flighty, and possibly are larger. This might be a coincidence as I've not incubated and hatched enough colubrids to base a theory on it, but I think it is better to err on the side of lower temps, than high temps.

Ryan

[vanderkm]

I will be very interested to see how this works out for you - especially with respect to hatchling size and temperament. We have always used 82 degrees, no substrate in a humid incubator (Thermos cooler with water heated by aqauarium heater) but might consider changing if the result was larger hatchlings due to slower incubation. It would certainly save on costs and hassle to be able to keep them at room temp. We haven't had problems with abnormalities in the past, other than one cal king clutch that was really bad from when it was laid. Definitely keep us posted,

mary v.

[snakewhisperer]

I use a large clear rubber maid with loose shredded paper on the bottom with a pail of water on one side with eggs in vermiculite on other. The water side gets a heating pad under it on low with the lid closed it keeps the temp at 80 and 85% humidity. I have 100% hatch with only one problem feeder last yr. I didn't pick the vermiculite ....I did an experiment this yr and let the snake do the picking as I put 3 different substrates in same containers and no additional heat under 1 had peat 2 had aspen 3 had vermiculite. She went into all of them in the days before laying.

[alex]

I think a cooler temperature will definately decrease deformity rate, but I too am skeptical of extremely low incubation temperatures... it's been well documented that cold has produced some spectacular fetal deformations (i.e. Pendlebury, can't remember the year offhand)

I'm kind of interested in the claim they were larger - either standard incubation is heat stressing the things until they hatch as soon as they can, or else it's wishful thinking - a longer incubation period gives you longer to reabsorb the yolk, but it won't necessarily make you bigger. It's something people claim all the time... long gestations means your horse will have a dystocia and the foal will die, 'cause he's grown too big to fit. It's a bunch of crap. There's certainly a genetic component to fetal size.

It would also be interesting to see if it influenced things like neonatal immunity and coordination. There's all sorts of musculoskeletal problems associated with abnormal gestation, but as snakes don't have limbs I doubt most notice.... ditto on disease. We don't expose them to much early in life.

[gonesnakee]

I just throw them on the tops of cages, shelves etc in the snake room in styrofoam boxes. The eggs themselves being in small rubbermaids with media (vermiculite or perelite or both) & sometimes right in it or on eggcrate. Temps probably around 80ish usually upto 85 maybe, dipping to high 70's. Don't keep track anymore LOL Only time I have to worry is for the second clutches when its really hot in the summer (not too often) & then its just a matter of moving them down to the floor, no biggee. Last year was the first year I used an incubator actually for Colubrid eggs since my first year. Big Dan had an empty one so he brought it by & I filled it up & still had boxes in the snake room LOL. I incubated them at 84 in the incubator. I've had pretty good luck "winging it" only usually losing eggs due to being in too wet a substrate or just because. I noticed that the incubator ones suffered similar "losses" to the stryofoam boxed ones anyhow. The helix controlled steady temp didn't make a big difference there, same, same. Anywhere from 70-90 will work, but high end temps mean risks. Low 80s works great. I think genetics still plays the biggest role in big healthy hatchlings. Mark

[alex]

That's just the thing with herps - good genetics leads to good hatchlings, but in these guys temperature is critical for allowing normal embryonic development, otherwise it's actually interfering with development at the level of individual genes and protein transcription/translation - hence the original discovery of the narrowly named heat shock proteins, which act as chaperones in times of protein structural stress.
Mammals who thermoregulate control this - and women who are pregnant get much more sensitive to temperature as a sort of self-preservation thing (especially now that fetuses are shown to metabolically affect us so much, like the recent discovery with ecclampsia being fetally mediated). A reptile egg is at the mercy of the environment, and embryos/foeti are incredably sensitive. Stressors like temperature can also induce an expression of a pathological trait - a human example is that thalidomide only caused phocomelia in babies who had the gene for it - it lowered the threshold for expression rather than causing a specific developmental defect in all foeti exposed to it.
It's also one of the reasons amphibians have such huge genomes (something like 17 pg on average) - undoubtably a good chunk of that is to deal with being functional through metamorphosis, but they have their developmental pathway for each temperature in their range - i.e. each degree difference or so triggers the same protein production but differently. It's amazingly complex, and I'm not sure how much our oviparous reptiles devote to a similar complex system. They only have 2.25 pg on average, which is slightly smaller than euplacental mammals.