Differentiate their gender (must be at the age of 4<):
- Have longer claws
- Cloaca is further away from plaston
- Longer & thicker tail
- Shorter claws than male
- Cloaca is closer to plaston
- Shorter tail
- Usually bigger in size
Before breeding them
Consider if you have enough space, whether you are capable of incubating the eggs and what you are going to do when the eggs hatched. Are you able to take care of the hatchlings? If you don't want them to mate and breed, then separate the male and female turtle when they reach maturity age.
If you have decided upon breeding them, feed the female with more calcium rich food so that she can produce better quality eggs. Guppies' bone, chicken egg shell may provide her with calcium.
They can start mating once they are about 5 years old and unlike some other turtles or tortoises, the males doen't need to fight with another males to win a female over. No delibearate interference is needed to get them to mate. But you just have to get two sliders of different sex together.
The mating dance:
The male will 'tremble' his front legs and claws in the face of the female. Sometimes he will bite her and swim around her. Excessive biting is no good and it would be better to separate the two turtles before there's injury. If the female accept him, he will ride on her back (facing the same direction as her) and they mate. The male needs long claws so that he can hold onto the female's carapace. If the female is relunctant, male may bite her or simply walk away.
It doen't take too long about 15 minutes. They mate in the water, so don't place them in water too deep or the female will have difficulty getting to the surface for breathing.
If the mating is successful. The turtle will probably lay eggs. I am not sure how long it stays pregnant. When it is pregnant, it might not eat much and gets rather choosy. It most likely will lay eggs in springtime.
It is likely to lay eggs in the morning (that may varies with turtles). There might be greenish discharge if it lays it's eggs in the water (that may not be the case for all). Females can hold their eggs if they can't find a comfortable environment to lay their eggs. So it's best to provide them with a good egg-laying area. It can be soil or sand and must be of big enough area for the turtle to fit itself in and of more than 5" depth. When it wants to lay eggs, it will probably be very restless and digs a lot.
Eggs are white and quite fragile when first laid (I think it hardens over time becoz my slider's do). It is usually laid in soil or sand about 3" to 10" deep. If possible, watch your turtle lay the eggs, it can be for interest but the main reason is to prevent predators like crows and cat/dog from getting to the eggs when they are laid outdoor. What you can do is 'cage' the area securely with wire etc. Otherwise you might want to take it indoor to incubate. If without proper egg-laying area, the turtles might just lay them in water. Take the eggs out immediately before they drown. Do not toss and turn the egg, carry it as gently as posible as the position it is in if you need to transfer it to incubate or else the baby might drown in the yolk. Might harden over time. I am not very sure how hatchable(fertilised) eggs are like because I have yet hatch turtles eggs. The condition need to be of 28-30 degree celcius, and humid. 60-100 days before it will hatch and not all eggs will hatch, only if you are very lucky. See incubation.
Hatchlings are very small and each has a yolk sag on it's tummy, do not do anything to it. The hatchlings will absorb nutrients from it for a day or so and then the sag will drop off. Hatchlings needs careful handling and usually has weaker immune system. Feed them small pieces of softer food. Check out baby sliders for more information.