Breeding

In the red-eared slider turtle—like many turtles, alligators and crocodiles, and some lizards—the sex of a growing embryo is by the temperature at which it is incubated. Cooler temperatures cause an embryo to grow up as a male. For example, if eggs are incubated at 26.6°C, all eggs will be male. In contrast, if a clutch is incubated at 31°C, all eggs will be female. A 1:1 ratio is found at about 29.2°C.

This effect is seen, it is thought, because higher temperatures speed the conversion of testosterone to estradiol. Embryos incubated at a warmer temperature are thus exposed to more estradiol during the critical period for sex determination, and they become female.

It has also been found that certain synthetic estrogens can override the temperature effect. For example, administering certain PCBs to eggs incubated at all-male or male-biased temperatures produces more females than expected on the basis of temperature alone.

Maturity age

The Red-Eared Sliders will be mature enough to breed at about 5 years of age, then the female shell size is about 15 cm (6 inches).

Mating tank

Use a 100L (30 gallon) tank. Keep the water warm but shallow, about 10cm (about 5 inches), since during mating the male get so concentrated that he might forget that the female has to breath.

Mating dance

The mating dance of this species is very elaborated and interesting to observe. The male swims towards the female, and starts caressing her face with his long front claws. He might also swim around her in circles. He might also strike her front shell lightly with his claws. This looks as if his front legs are trembling. If she is receptive, she will accept him, otherwise a fight might start. If after 45 minutes, the female is not receptive to the male's dance, you should remove her from the tank and try again in about two days later. The mating itself takes about 15 minutes.

After mating

It is advisable during pregnancy to keep the female separate from the male, so that she will not get disturbed so much. You should handle her ONLY when absolutely necessary. Keep the water very clean and give her enough space. Heating is also very important as they will spend a lot of time basking to warm themselves and the eggs inside. You might notice a change in the appetite of the female, she might refuse to eat. This is normal, so don't stop continuing offering her food and consider a dietary change, she might feel inclined to eat certain things only. Like many pregnant mama's she may have specific preferences at this time.

Nesting quarters

Prepare a 65L (20 gallon) tank with about 10 cm (4 inches) of potting soil or soil/vermiculite mixture.

Laying eggs

The average gestation period is two months, but if she doesn't find a suitable place for laying her eggs, she might retain them inside. During the last two weeks you will notice that she will spend more time on land, sniffing and digging around in order to find a proper place for laying her eggs. At this point, you need to place the female in the nesting quarters. At this point, you need to place the female in a tank with about 4" of potting soil or a soil/vermiculite mixture. Try to watch her as much as you can to see where she lays the eggs. She might lay from 2 to 20 eggs. There are pro's and con's to both leaving and removing the eggs.

Removing the eggs or not

There are pro's and con's to both leaving and removing the eggs.If the eggs are left, you eliminate the risk of damaging the eggs.

Keepers who have a good basking area prefer to leave the eggs where they were laid, a good point of doing so is that they do not need to handle the eggs, digging them out could damage the eggs or some of them. However, if left buried, they are difficult to monitor. Also, if an egg is infected with a fungus, it may spread to the whole nest or the hatchlings may have a difficult time digging their way out.

Incubation box

If you decide to remove the eggs to incubate them, you will need to prepare an incubation box. You can use a large plastic sweater box or a plastic shoe-box. Plastic boxes are good since they can be thoroughly cleaned and keeps well the moisture. Drill a series of small holes into the lid for ventilation (no more than 1/4" in diameter). Make no more then dozen holes of about a quarter of en inch in diameter. Then, set up a bedding in the container of about 2 inches of vermiculite. Use the heavy grain rather then the fine one. Moisten the vermiculite evenly. Make sure it is kept damp (but not wet).

Removing the eggs

This process has to be done very carefully. Scoop back small sections of the substrate around the nest, very slowly and carefully, trying to feel the eggs with your finger at the same time. Once you find an egg, before you remove it, get a water based felt-tipped marker and make a small mark on the top of the shell. This is important since you need to place the eggs in the same position the turtle layed them. Once you have transferred all the eggs to the incubation box, set it somewhere where it will not be disturbed. check the eggs a few days after by just removing the lid, but don't handle them! Check for rotten eggs, which you should throw away immediately. If you see that as egg is developing fungi, you can remove the fungi with a 50/50 solution of antiseptic mouthwash and water, which you should apply carefully with a paintbrush.

Hatching

You should start to observe the eggs more carefully about 55 to 65 days after they had been laid. Hatching time is coming! The eggs should hatch in about 80-85 days. Once the time comes, the hatching will cut the eggs shell with something called "egg tooth", which falls out about an hour later and never grows back. If they don't feel secure, they will remain inside their shell. They may remain in the shell for an additional day. Do not take them out, they might not come out until the following day. Once they come out, you notice a small sack hanging out of their bellies. This is the yolk sac that fed them while they were incubating. DO NOT remove this sac, removing it can kill the newborn. It is better to wait until it drops on its own. Once it drops, you will notice a split in the plastron. This will heal by itself too, you don't need to treat it.

Caring of the newborn

Set the newborns in a 65L (20 gallon) tank per dozen. Give them a basking area and a water area(shallow water), not to deep. Baby sliders may take a while to become confident swimmers and can even drown if not provided with an easily accessible land area. Newborns need to master the art of floating and staying underwater for long periods of time. Newborn Red-Eared Sliders can actually drown if you neglect them dry land. Once they are in their tank, start feeding them. It is important to get them to eat. Start offering them items on the proper Red-Eared Slider diet, you might have to chop the food you offer, since they are small babies. This includes chopping earthworms, mealworms, crickets. This might sound disgusting, but you will get used to it after a while. As with adult Red-Eared Sliders, newborn need to have their full spectrum light. So don't forget to include a good lighting in the tank. The full spectrum light will help the newborn shells to harden. Keep the water clean. if you don't have a filter, change the water at least 3 times a week. This is very important since baby Red-Eared Sliders are more prone to getting eye infections that can leave them blind for life or even kill them than adult Red-Eared Sliders.

Breeding Conditions

The most consistent breeding results are obtained with Red Eared Sliders that are cooled down during the winter. It is recommended that beginning in January Red Eared Sliders be kept at 50-60 degrees F, for a period of 6-8 weeks. This can usually be done by placing the Turtle enclosure in a cool room of the house. Any heating units should be turned off, and hours of lighting over the basking area should be cut down to 10 hours. Sliders will usually not feed at these colder temperatures and spend most of their time in the water section. During that time, the day length should be reduced and the lights placed on a timer so that they are on only ten hours a day. Males will often attempt breeding with females at these colder temperatures and some experts feel that successful breeding frequently happens during the cooling period. One view is that the sluggish behavior of females allows for more ready breeding by males. After 6-8 weeks, the Turtles should be returned to normal maintenance temperatures, they should be placed on an optimal feeding schedule. Egg-laying will occur from spring through summer. Some experts keep their Turtles outside during that time in an enclosure that includes a water area, a land area, and an egg-laying section consisting of a large container with 12-16 inches of moistened garden soil or of a moistened peat moss and soil mix. This provides an egg-laying area that is always available when a female turtle is ready to lay. Other experts closely monitor their turtle's behaviors. Female Turtles that are nearing egg-laying typically go off and feed and become unusually active. Once this is noticed, experts will remove the female turtles from the enclosure and place her in a large container with 12-16 inches of soil. Female turtles that are ready to lay will usually do so within 24-48 hours. Red Eared Sliders will lay several clutches of 4-25 eggs per breeding season. Depending on several factors, including the age and size of the Turtle and the feeding and maintenance schedules, egg clutches will be laid at intervals of 2-4 weeks. Specialist breeders will consistently obtain 5-8 clutches per year from large adult Red Eared Sliders. These frequent clutches are only possible when special attention is given to the feeding of females between clutches. High protein diets during the breeding season will increase multiple clutching success.

Incubation

Following laying, the eggs should be removed and placed in a container with moistened vermiculture (equal parts of land and water, by weight). The eggs are placed on the surface of the vermiculture in small finger-made depressions to prevent rolling. The top of each egg should be marked using a magic marker to assure that they remain in the same position. The up side should remain on top throughout the entire incubation. The container is kept sealed except for a few holes for aeration and the eggs are then incubated at 80-82 degrees F. The eggs should be regularly inspected, and the vermiculture lightly sprayed with water to retain moisture. Hatching should occur in 55-65 days. As with many Turtles, the sex of Red Eared Sliders appears to be temperature-determined during the first weeks of incubation. Eggs incubated at 75 degrees F, will yield primarily males and eggs incubated at 85 degrees F, will yield mostly females. The suggested incubation temperature should result in hatchlings of both sexes.