How common is it for kings to retain sperm and lay viable eggs years later? I personally have not had this happen,or even a slug clutch, but my collection is small. Currently one of my kings is looking very gravid. She has not been bred this year or last. I am curious if it is likely a bunch of slugs or if I should prepare for possible fertile eggs, as she did have clutches the years prior. As it is, she has a few nest box choices regardless. Any advice/experiences?