Can pill bugs survive in water?
Pill bugs have gills because they are related to lobsters, crabs, and shrimp. They need water to survive, but it would probably kill them if they were just completely submerged in water.
"Organisms have basic needs. For example, animals need air, water, and food; plants require air, water, nutrients, and light. Organisms can survive only in environments in which their needs can be met." /l\ / This pretty much describes it. (Basically, pill bugs can survive without light. Indirectly, though, the plants they eat need light to grow, and they would die if they couldn't eat, obviously.)