Holding its egg sac, a creepy-looking spider sits on a bridge on Dorset Road in West Penn. Female spiders lay up to 3,000 eggs in one or more silk egg sacs. In some species, the females die afterwards, while females of other species stay alive and protect the sacs by attaching them to their webs, hiding them in nests or carrying them in their mouth. Some even attach them to spinnerets and drag them along while they hunt.