Sensitivity to Aerial Exposure: Potential of System-Wide Drawdowns to ManageZebra Mussels in the Mississippi River. Long Term Resource Monitoring Program

摘要

We report the results of five experiments performed during periods of loweredriver water level; in Pool 26 of the Mississippi River. Four experiments compared survivorship of zebra mussels (Dreissena polymorpha) and unionid mussels (Unionidae). Under mild spring conditions (March), survivorship zebra mussels was similar to that of unionid mussels, but during summer (July) survivorship of zebra mussels was lower than that of unionid mussels. A fifth experiment compared survivorship of 10 species of unionid mussels after 24 hours of aerial exposure. In general, survivorship of thick-shelled species, such as Amblema plicata, was greater than survivorship of thin-shelled species, such as Potamilus ohiensis. The experiment conducted suggest that drawdowns during warm summer conditions could have a profound, negative influence on zebra mussel demography and distribution.