Presenter(s)

Benjamin Strei

Abstract or Description

Zebra mussels Dreissena polymorpha are an aquatic invasive species that has been spreading quickly throughout Minnesota water bodies since 1989. Zebra mussels are known to change certain morphological conditions in lakes such as turbidity, phytoplankton abundance, and aquatic invertebrate populations. However, no study in Minnesota has shown a correlation between the infestation of zebra mussels and the health of a lake’s fish community. Therefore, the objective of this study is to determine whether zebra mussels have an impact on fish communities in Minnesota lakes. The Minnesota Department of Natural Resources has been collecting Lake Indices of Biological Integrity (Lake IBI) scores since the early 2000’s to measure the health of the lakes fish community. Lakes in Minnesota that had an IBI survey taken both before and after the introduction of Zebra mussels were included in this study.  The scores from these lakes were then graphed and analyzed by a paired t-test to determine changes in fish community health. Additionally, years since infestation and the change in the IBI score was graphed and analyzed using regression statistics. This determined the predicted change in score for every year that the lake has been infested. A significant difference in IBI score change was found in scores before versus after infestation, however, no significant difference was found between the years since infestation and change in IBI score.

Mentor

Andrew Hafs