Using ROVs
Research teams use a tool called a remotely operated vehicle, or ROV, to help them identify underwater areas from which they will later gather data. The ROV is essentially a small, unoccupied submarine that is controlled from the surface. Cameras on the ROV collect underwater video footage - certainly an easier and safer way than diving to find out what's happening below the surface.

After the team gathers video images using the ROV, they head out into Lake Michigan or Lake Superior. From the ship, they take samples of physical, chemical and biological features of the sites they've chosen - for example, characteristics like temperature, light levels, pH, oxygen levels, and the presence of chlorophyll and bottom-dwelling animals. After sampling, the researchers return to the lab and carry out chemical and biological measurements of their data. Finally, researchers calculate, graph and interpret their data.