SS1.03 Zooplankton Response to Climate Variability
Date: Monday, June 10, 2002
Time: 2:45:00 PM
Location: Lecture Theatre
 
KimmelDG, University of Maryland, Cambridge, USA, dkimmel@hpl.umces.edu
Roman, M, R, University of Maryland, Cambridge, USA, roman@hpl.umces.edu
 
INFLUENCE OF WATER QUALITY PARAMETERS ON ZOOPLANKTON ABUNDANCE AND SPECIES COMPOSITION IN THE NORTHERN CHESAPEAKE BAY: IMPLICATIONS FOR CLIMATE CHANGE
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A 16-year (1985-2000) time series for 14 fixed stations in the northern Chesapeake Bay and its tributaries was analyzed for trends in mesozooplankton abundance. Regression tree modeling revealed that interannual variation in freshwater input is a major factor influencing mesozooplankton abundance in mesohaline areas of the bay. Years of high freshwater input resulted in an overall increase in zooplankton abundance and a change in community composition. High flow years were typified by a bloom of the copepod Eurytemora affinis. This bloom may persist for multiple years regardless of subsequent variation in freshwater input. The other dominant copepod, Acartia tonsa, was not well correlated with freshwater flow. Several recent climate change models predict an increase in Susquehanna River discharge and thus freshwater input into the Chesapeake Bay. Our models suggest that this scenario would likely lead to an expansion in the range of E. affinis and an overall increase in mesozooplankton abundance in the northern Chesapeake Bay. Such an increase would have an impact on fisheries recruitment as E. affinis is an important food resource for anadramous fish.