Water bugs live and grow in interesting ways, with most starting life as an egg. When water bugs hatch, some look like their parents and have skins that grow, such as snails and leeches. Some have hard skins, such as yabbies, that need to be shed so they can get bigger. Others look like their parents but are wing-less, like the dragonfly nymph. Still others hatch looking nothing like their parents and have soft bodies, eventually transforming themselves into winged adults.

Some water bugs like to munch on dead plants and animals found at the bottom of the stream. The water bugs that suck up the yuk and turn it into food for plants and algae are known as detritivores (pronounced det-try-te-vorz).

Other water bugs prefer to eat plants and algae and are known as herbivores (pronounced herb-ee-vorz). These types of water bugs are either scrapers or shedders depending on the way they eat.

Many detritivores are also herbivores because the type of mouthparts and digestive system needed to eat plants that are either dead or fresh are similar.

At the top of the water bug food chain (what animals eat, which animals eat other animals) are the predators like the dragonfly nymph or hydra, which eat smaller animals. They are carnivores (pronounced car-nee-vorz). Life as a predator water bug is not all hunting. They, too, are prey for larger animals such as fish and birds.