The life cycle for avian schistosomes is similar to that of human schistosomiasis. Adult flukes mate and produce eggs which are usually excreted with the bird's feces. Once in the water, the eggs hatch, liberating many miracidia. The miracidia, using their cilia, swim around eventually finding a molluscan intermediate host, usually a snail. In the snail, the miracidium develops into a sporocyst, which in turn develops into a daughter sporocyst or redia. Eventually, the sporocysts and rediae develop into cercariae. The cercariae exit the snail through feces and penetrate the skin of new avian hosts, migrating to blood vessels of the bird and mature into adults. Their final location is the veins which feed the gastrointestinal tract. There they complete the life cycle by laying eggs which pass into the gut and are released into the water. Humans become infected with cercarial dermatitis when they are exposed to the dermatitis-producing cercariae.