I have had a pair of African Blacks for a year now that, when not eating or sleeping, mate. They mate constantly but I have yet to see any babies. Is it that the babies are dieing after hatching? What are the most common causes of this? I have them in coconut substrate, keep it somewhat moist, have two pieces of decaying wood buried, and feed, lettuce, cucumbers and oak leaves when I can get them. (Btw, I can't acquire oak leaves very easily. How are maple leaves?)