A GIS for a large river: Fishes, bathymetry, water velocity, sediment, and woody debris

Stream fishes have specific habitat preferences. The use of a Geographic Information System (GIS) to analyze and view fish distributions and habitat parameters provides numerous advantages over previous analyses. We collected channel bathymetry, water velocity, and streambed composition using an Acoustic Doppler Current Profiler (ADCP) deployed from a USGS boat and interfaced with a Differential Global Positioning System (DGPS) receiver, for a 10-km study reach of the Wabash River in Lafayette, Indiana. Within one week of collecting habitat data we used three boat electrofishers to simultaneously collect fishes through the same reach. Individual fish were assigned latitude-longitude coordinates when they were captured using GPS units. These data allow us to test multiple hypotheses ranging from asking if some species tend to co-occur less than expected (competition or predation), to testing for species habitat preferences, to models of hydrology, substrate variation, and fish assemblages. We collected 2,773 fishes in 40 taxa that will be presented at three spatial scales with habitat variables.