Changes in invertebrates and their functional feeding groups downstream and upstream of an impoundment.

Abstract

Changes in invertebrates communities of Maple River, Michigan, downstream and upstream of an impoundment were investigated during the summer of 1998. Alterations in substrate, depth, temperature, FPOM, and current velocity due to an impoundment were examined as possible factors influencing the diversities and abundance of invertebrate functional feeding groups. A Surber Sampler collected invertebrates and a plankton net sampled suspended organic matter in the water column. Standard methods were used to collect remaining data. No correlation between FPOM and functional feeding groups was identified. Faster current velocities downstream may provide resources to the reduced diversity, but increased abundance of invertebrates downstream of an impoundment.