A quantitative comparison of zooplankton upstream and downstream from the Lake Kathleen impoundment on the Maple River, Emmet County, Michigan.

Abstract

Purpose = To quantitatively analyze and compare the zooplankton on the Maple River and its branches upstream and downstream from the Lake Kathleen impoundment. Summary 1. Samples, with a Clarke-Bumpass sampler, were taken upstream and downstream from the Lake Kathleen reservoir on the Maple River. 2. There is a diurnal variation in organism density below the dam. There is a two-fold increase in zooplankton crustacea after dark. 3. The stream eliminates the zooplankton from the reservoir within 6 km downstream of the dam. 4. According to zooplankton density, the fish productivity over the total length of the stream has probably not decreased. 5. The housing development should release as few nutrients as possible into the reservoir to prevent a significant prolonged alteration of the downstream environment.