Recolonization rate and preference of Zebra Mussels (Dreissena polymorpha) on living and non-living material.

Abstract

Zebra mussels (Dreissena polymorpha) are an invasive species in Douglas Lake that have disrupted the aquatic community, such as decreasing the abundance of food for native bivalves. They have major consequences on the population of native mussels and fish species, such as decreased abundance and possibly extinction. To understand how to control the increasing population of zebra mussels, the preference of substrate for colonization and the recolonization rate of the species must be determined. To determine this rate we measured, marked, and removed zebra mussels off of live and dead native mussels. In addition, we introduced clean rocks to observe the colonization rate of zebra mussels on them. We then recollected the substrates and determined recolonization. Our results showed that zebra mussels have no preference for the substrate that they recolonize. The average recolonization rate of each substrate was 0.08 mussels per day. From our observations, we suggest a protocol for controling the population of zebra mussels and the impacts that they cause on the aquatic community. The protocol may help us create a refuge for native mussels to sustain the population in Douglas Lake.