Meeting Abstract
Most zooplankton species in inland lakes exploit a life cycle with active life stages occupying the water column and dormant life stages resting in the bottom sediment. Because of this pelagic-benthic coupling, monitoring zooplankton communities in both locations can provide a powerful view of the health of lake ecosystems. The primary objective of the present study was to assess the state of the active zooplankton community in a cooling-water source (Lake Sutton, North Carolina) for a former coal-fired power plant by monitoring zooplankton diversity and abundance in the water column. The secondary objective was to assess the presence of zooplankton embryos in the benthos by identifying dormant life stages of crustacean zooplankton in sediment basins. The present study demonstrated that (1) the diversity of the active zooplankton community decreased over the last 30 years, (2) few zooplankton species have predictable succession patterns over the course of a year, (3) early life stages of copepods are the most common crustacean zooplankton in the water column, and (4) the diversity of embryos in the sediment is extremely low. Together, the decrease in diversity and low recruitment of some species to adulthood indicate that zooplankton in Lake Sutton face serious spatially heterogeneous challenges to recruitment from dormant egg banks that jeopardize community stability, and, in turn, the long-term viability of recreational fish stocks. Managers of freshwater resources should take note; maintaining a stable zooplankton community may decrease the cost of maintaining important recreational fish stocks.
