Several interesting groups of insects-the mayflies, stoneflies and caddisflies-spend their lives in two phases. During the longer early phase they live in freshwater and then emerge into the air for their adult phase to mate and disperse. Because they spend their young life in freshwater environments they are indicators of the health of rivers and streams and have been used as 'bio-indicators' as some species have been found to be more sensitive to environmental changes such as pollution and sedimentation than others. However it is often difficult to identify species. So an integral part of this survey was capturing high quality images for identification and doing the necessary work to connect the larval and adult phases of each species.