Saltwater crocodiles reproduce during the wet season, in Australia from November to March. There is a complex mating ritual which includes them rubbing their heads and bodies together, before they mate in the water. The female builds a nest with plants that she breaks off with her teeth, and then pushes together with her back legs. A female crocodile can lay up to 60 eggs at a time. These eggs are large, with a hard shell. They take about three months to hatch. If the temperature in the nest is less than 32 degrees Celsius, the baby crocodiles will be female. If the temperature is between 32 and 33 degrees the babies will be male. When the crocodiles hatch out of the eggs, the mother will carry them in her mouth to the water. Few of them survive in the wild and grow to be adult crocodiles.