SS1.08 Sensory Ecology, Neurophysiology and Behavior of Zooplankton
Date: Monday, June 10, 2002
Time: 4:45:00 PM
Location: Carson B
 
LindénLE, University of Helsinki, Helsinki, Finland, eveliina.linden@helsinki.fi
Lehtiniemi, M, , Finnish Institute of Marine Research, Helsinki, Finland, maiju.lehtiniemi@fimr.fi
 
THE EURASIAN WATERMILFOIL (MYRIOPHYLLUM SPICATUM) CAUSES HIGH MORTALITY IN BALTIC LITTORAL MYSIDS (NEOMYSIS INTEGER AND PRAUNUS FLEXUOSUS)
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Myriophyllum spicatum is a common macrophyte species in shallow bays of the Baltic archipelagos. In summer 2001 we conducted aquarium experiments where we found that M. spicatum causes extremely high mortality (72 – 89 %) within minutes in the two most common littoral mysid species in the northern Baltic Sea, Neomysis integer and Praunus flexuosus. These mysids are important prey for a number of fish species, including gobies and perch, which is the main target of recreational fishery in Finnish coastal areas. M. spicatum has been known to be toxic to certain aquatic organisms, probably due to the polyphenols released by the macrophyte. This is, however, the first time a larger aquatic invertebrate has been shown to be affected. Our results suggest that mysids do not dwell on areas occupied by M. spicatum, and since it is a dominant species and strong competitor in the study area, this finding may influence the distribution of littoral mysids, and thus their predators, the fish. Further experiments will be conducted in summer 2002 to better understand this phenomenon.