Pilot Study of Spatial Patterns of Ichthyoplankton among River Reaches andHabitats of the Upper Mississippi River System

摘要

A pilot study was conducted to evaluate ichthyoplankton communities amongselected habitats in the upper Mississippi River. Catch data were used to compare differences in catch among habitat types and to relate these differences to water quality. Sampling design characteristics to describe spatial and temporal differences in the ichthyoplankton community were recommended. Samples were collected by LTRM field station personnel in Pools 8, 13, and 26 of the upper Mississippi River and in the lower section of the Illinois River. About 30% of the samples processed had some sort of collection or recording error. Suggestions were presented to reduce collection and recording erros. Catches in main channel habitats were dominated by freshwater drum Aplodinotus grunniens, whereas cyprinids were dominant in the vegetated backwater habitats. Greater effort should be invested in sampling more stations within a habitat type rather than multiple replicates at fewer stations.