I have a rooster, he's about 3 months old. My family and I are planning on having some chickies. I read online that hens will only hatch fertilized eggs in the spring, is this true? If so, what part of spring do the hens start laying fertilized eggs? Is it all season? Also, I need to know some warning signs that the rooster will start mating. And the pullets haven't started laying yet, which means they're not fertile yet, right?