Zebra and Quagga Mussel Dry Weight Information; Lake Erie 2014

Impacts of dreissenid mussels (Dreissena spp.) on Great Lakes ecosystems are well documented, and a better understanding of mechanisms that cause variation in mussel abundance is needed. An outstanding question is how much mussel biomass is consumed by fish predation. A significant difficulty for investigating mussel consumption by fish is that mussels in stomachs are often a mix of crushed shell and flesh. Here, we provide information on the relationship between shell-and-flesh dry weight measurements and flesh-only dry weight of two species of dreissenid mussel, quagga (Dreissena rostiformis bugensis) and zebra (Dreissena polymorpha), to be used in formulating conservative estimates of flesh-only dry weight in fish diets. Dry weight analyses were conducted to simulate stomach contents ranging from small (individual mussels) to large (aggregate of mussels). All measurements were taken at the USGS Lake Erie Biological Station in Sandusky, Ohio using quagga and zebra mussels collected from Lake Erie in May, 2014.