Habitat Use By Shovelnose Sturgeon at All Life Stages

River modifications may have detrimental effects on biota that depend on river systems, so research is needed to understand these effects and direct management efforts.  We evaluated the relative occurrence of age-0, juvenile and adult shovelnose sturgeon among multiple macrohabitats and mesohabitats in the Middle Mississippi River.  Shovelnose sturgeon (Scaphirynchus platorynchus), were sampled across four seasons from June 2002 through June 2013. At each sampling site macrohabitat type was documented and categorized as channel border open (i.e., dikes absent), channel border dike (i.e., between wing dikes), main channel, island main channel border, island side channel border, and tributary mouth. Furthermore, more fine scale mesohabitat data (depth, velocity, and substrate) were recorded as well. We completed 8,432 sampling efforts using trawls, gill nets, and trotlines which were deployed consistently at random sites throughout the study years.  A total of 23,673 shovelnose sturgeon, were collected during this evaluation.  Overall at all life stages, island areas and channel border locations exhibited the highest catch rates while main channel and tributary locations were used much less frequently. However, marked differences in mesohabitat use by life stage existed.  Age-0 sturgeon exhibited specific mesohabitat use while juvenile and adults were mesohabitat generalists.