A survey on the occurrence of Dreissena polymorpha and their impact on two unionid bivalve species, Anodonta grandis and Lampsilis radiata in Douglas Lake, Michigan.

Abstract

Zebra mussels invaded Douglas Lake in 2001. Since their invasion their numbers have risen. A survey was done in order to map total population and preferred substrate attachment at various sites in the lake. Over 3,000 Dreissena polymorpha were found in the greatest numbers on rocks (23%), pebbles (18%), and shells (18%). A second study was then carried out to examine if zebra mussel attachment had an impact on two native mussel species biomass. Though no relationship was found, there is a possibility that large effects will be notable after another year of zebra mussel growth. Continued study of the impact of zebra mussels in smaller lake systems is critical for understanding the impact of native bivalves small inland lakes elsewhere in Michigan.