Surrounding land-use and in-lake data were collected to determine environmental variables influential in structuring centrarchid assemblages in oxbow lakes of the Mississippi Alluvial Valley (MAV) and to suggest environmental manipulation strategies that may improve the fisheries of these systems. I sampled 53 oxbow lakes using boat electrofishing and land-use data were summarized using ArcView GIS. Non-metric Multidimensional Scaling separated centrarchids according to water quality tolerance. Centrarchid composition was related to land-use, water clarity, maximum depth, connectivity, primary productivity, and physicochemistry as determined by Canonical Analysis of Principal Coordinates. Canonical Correspondence Analysis rejected the null hypothesis of no relationship between land-use and centrarchid proportional composition. Environmental variables were related significantly to centrarchid composition. Based on these data, a general fisheries management plan for oxbow lakes of the MAV was proposed.

Fish assemblages from 54 oxbow lakes in the Mississippi Alluvial Valley were sampled to identify relationships among environmental variables and fish biodiversity in floodplain lake ecosystems. Environmental variables deterministic over fish biodiversity showed a hierarchical organization and were classified as primary or secondary depending on if one variable was considered to govern another. Primary variables included depth, surface area, surrounding land use, and degree of lake-river interconnectedness. Secondary variables included suites of water quality and primary productivity variables. Maximum depth and percentage of agricultural land surrounding lakes showed strongest relationships with other ecosystem components, significantly influencing water quality, primary productivity, and fish biodiversity. I found contrasting results regarding effect of lake-river interconnectedness on fish biodiversity, but maintain that connectivity is nonetheless an important floodplain lake ecosystem component and suggest that floodplain lake management efforts focus on depth, percentage of agricultural land, and restoration of connectivity.