An Analysis of Spatial and Temporal Changes in Fish and Benthic Macroinvertebrate Communities Associated with Zebra Mussel (Dreissena polymorpha) Abundance in the Huron River, Southeastern Michigan

Abstract

This study examines the effects of the introduction of zebra mussels (Dreissena polymorpha) on fishes and benthic invertebrates in the middle stretch of the Huron River in southeastern Michigan. Fish community surveys were conducted during the summer of 2008 and compared with data taken in the same area in 1977 and 1993, before the introduction of Dreissena. No significant difference was detected in fish species richness and diversity between sites with mussels versus those without. However, several significant changes in fish community composition were detected, with fishes belonging to the families Centrarchidae, Percidae, and Ictaluridae increasing significantly and Cyprinidae and Catostomidae decreasing significantly as Dreissena density increased. Historical data showed a significant decline in the abundance of cyprinids and catostomids after the introduction of Dreissena. Benthos sampling conducted in 2008 and 2009 showed a dramatic increase in the overall abundance of macroinvertebrates associated with increased mussel density, as well as a significant increase in the numbers of chironomid larvae and amphipods and a decrease in the number of oligochaetes. Results of this study indicate that the introduction of Dreissena to the Huron River has not resulted in a loss of fish biodiversity, but communities of fishes and macroinvertebrates have experienced changes in species composition.