The Clemmys breeding

Last April-March the male chased the female. She usually escaped, but one day I saw them mating.

Sometime later, in late May, the female's behavior changed: I often found her walking in the land area of the pen. When she realized that I was watching her, she went back to water. In the wild, when they need to nest, they migrate to look for the right place, sometimes far away from the water. Could it be that she wanted to nest?
One day I picked her up and I palpated her through the inguinal space. I managed to pass my hand smaller fingers. I gently turned her one side and the other and I thought I felt eggs, but I wasn't sure at all.

This species uses to nest in the evening and through the night. Therefore, each night, when I came back from work about 21:00 I had a look at the pond. Also in the midnight, with a torch, trying not to alarm the neighborhood.
On May the 20th, at 21:00, I found the female digging a hole. I filmed her throughout the process, until  1:30. During all this time I noticed the nocturnal life around the pond: mosquitoes, slugs, snails, ants, spiders, tarentolas...When the nest was covered, she wasn't satisfied (although it looked perfect to me). She stepped on it, paused, I thought she had finished... but she started again. More than half an hour like that.

Female nesting at night

Covering the nest with the rear legs

She made the nest among the weeds

While she covered the nest, I had time to think about the eggs. I could leave them in place, to incubate naturally, or dig them out and put them in the incubator.

Geographic variation in reproduction in a freshwater turtle (Clemmys guttata). Jacqueline D. Litzgus and Timothy A. Mousseau. http://www.laurentian.ca/NR/rdonlyres/F98DC713-A788-4A95-8CBA-C23BE8EC11DF/0/LitzgusMousseau2006Herpetol62_132140.pdf

According to this article, it is thought that they do not nest in a particular substrate or habitat but in the place where the incubation conditions are better. In some part of their range it is in under tree canopy, in other places in open areas. Sometimes they nest in woody debris or leaf litter,even under moss. In other places they nest in the soil in open areas. 
 In the pond the land area is not so variable and they have no choice. Would they have developed there? It was a very exposed place, and in the summer the soil dries and hardens. I decided to try the incubator.

There were 4 eggs. I used a Jaeger incubator with vermiculite as a substrate. I put two eggs at 30ºC and two at 25,5ºC. The humidity was high. In the beginning it all seemed to go well. A white patch appeared in the eggs and it usually means fertility. Sadly I lost the pictures of this moment.

Some weeks later my mother in law told me that one of the turtles had been digging a hole in the afternoon. I looked for the nest and I found it, although it was very well camouflaged. If she had not told me, I would have never noticed that nest. Curiously the turtles nested in the afternoon. There were three eggs. I put two at 25,5ºC and one at 30ºC.

In this species, as in many other chelonians, the sex of the hatchlings is temperature dependent.  At higher temperatures you obtain females, at lower temperatures males. In mid August I candled the eggs with a torch. I had a deception because only one of the eggs looked fully developed.

 

Infertile egg

Unlike in the previous picture, in this egg there had been some embryonic development. By now it should occupy all the egg, like the one in the next picture. All the other eggs looked like that. I incubated them for some time until they rotted (they cracked and smelled bad)

Egg ready to hatch

From this last egg, incubated for male, a very beatifull turtle hatched

Detail of the "egg tooth" that they use to open the egg from inside

I didn't put the hatchling with the adults, I wanted to have  him in a smaller space. I put him in a tank, 1 x 0,5 mt, with a water depth of 20cm and plants, logs, rocks....
The last picture is not of a real situation, I had to put the hatchling there. I have never seen him out of the water, and I have hardly seen him in the water. He hides and he does it very well.  After some days not seeing him, I looked for it. I had to take out all the plants, rocks, etc until I palpated him hidden between the plant roots. He is very shy. I offered him worms, small fish... but he didn't touch them. I don't know if he fed since he was born. In the tank there were mosquito larvae and small water snails. He also had the yolk sac reserves.
I imagine this behavior is important when you are very small and so many animals can prey on you. 
He is now hibernating in a  bucket with a plant (roots included) and little water. He hides in the roots (they could also be useful to avoid accidental drowning). It is in a shed outdoors, in a cold place but without danger of freezing.
I don't know what failed during the incubation. I think it could be the humidity since the vermiculite tended to dry, especially at  30ºC. I also wonder now what would have happened if I had let the eggs in place to incubate naturally.