Document Type
Poster Session
Department
Environmental Science and Policy
Faculty Mentor
Karen Wilson, PhD
Abstract
Highland Lake in Windham, Maine has suffered from algae blooms since 2017. These algae blooms may have been caused by top down effects (i.e., predation on zooplankton) or bottom up effects (i.e., nutrients). We evaluated the hypothesis that young of year alewives ( Alosa pseudoharengus ) can consume large zooplankton thereby releasing algae cells from grazing. We compared young of year alewife mouth gape width to the width and length of zooplankton common in the lake before the algae bloom. Daphnia (Daphnia magna) were the largest zooplankton measured, while nauplii (juvenile copepods) were the smallest. Overall, copepods were the most abundant zooplankton. In our final analyses, we will compare these zooplankton sizes to larval and juvenile alewife mouth gape to determine at what size alewife can consume important zooplankton. To measure alewife mouth gape we will use a specially constructed precision micrometer. These findings will provide a better understanding of the trophic dynamics of Highland Lake and one of several potential triggers of algal blooms in the lake.
Open Access?
1
Determining the Ability of Larval and Juvenile Alewife to Consume Zooplankton in Highland Lake
Highland Lake in Windham, Maine has suffered from algae blooms since 2017. These algae blooms may have been caused by top down effects (i.e., predation on zooplankton) or bottom up effects (i.e., nutrients). We evaluated the hypothesis that young of year alewives ( Alosa pseudoharengus ) can consume large zooplankton thereby releasing algae cells from grazing. We compared young of year alewife mouth gape width to the width and length of zooplankton common in the lake before the algae bloom. Daphnia (Daphnia magna) were the largest zooplankton measured, while nauplii (juvenile copepods) were the smallest. Overall, copepods were the most abundant zooplankton. In our final analyses, we will compare these zooplankton sizes to larval and juvenile alewife mouth gape to determine at what size alewife can consume important zooplankton. To measure alewife mouth gape we will use a specially constructed precision micrometer. These findings will provide a better understanding of the trophic dynamics of Highland Lake and one of several potential triggers of algal blooms in the lake.
