Zebra Mussels and Plankton

Introduction Data Collection and Analysis Results The Bottom Line

Methods

Water for the experiment was collected using the pump on board the R/V Melosira from a deep water site outside the Burlington breakwater in August 2002, and filtered through a 150 micrometer sieve to remove large zooplankton.  On return to the lab, lake water was divided evenly between sixteen 55 gallon barrels (200L per barrel). Each barrel had a raised platform of Vexar mesh constructed roughly 3 inches from the bottom to avoid resuspension of zebra mussel waste by currents induced by aeration.

A preliminary experiment was conducted in early August using just a zebra mussel addition and a control treatment (Run 1).  A second experiment in late August included a zooplankton addition, a zebra mussel addition, and a combined zebra mussel/zooplankton treatment and a control.  Over the course of a 96-hour experimental period, we collected samples for analysis of total nitrogen, total and soluble reactive phosphorus, chlorophyll a, microcystin (a toxin produced by some cyanobacteria), and phytoplankton, rotifer and zooplankton species composition a total of six times (at the beginning of the experiment – 0hrs, 12hrs, 24hrs, 48hrs, 72hrs, 96hrs).  Immediately following collection, samples were filtered and/or preserved as required for analysis.

Analyses of nitrogen and phosphorus samples were by persulfate digestion.  Plankton samples were concentrated and all individuals identified to the lowest feasible taxonomic group and counted.

Project Overview Plankton and Water Quality Blue-Green Algae Storm Water Chemical Mixture Tests Zebra Mussels and Plankton Contact Info

Home