Biomass and annual production of the freshwater mussel Elliptio complanata in an oligotrophic softwater lake

Abstract

SUMMARY. An extensive survey of Mirror Lake, New Hampshire, was carried out by divers with SCUBA to assess the importance of the freshwater mussel Elliptio complanata in this softwater lake ecosystem. Density (0.032 adults m−2), biomass (52 mg m−2 as dry organic matter) and annual production (6.4 mg m−2 as dry organic matter) of the mussel population are low when compared with results from other studies, corresponding with the general observation that mussels are scarce in soft, oligotrophic waters. We reject the traditional view that the low mussel density is a result of low calcium concentrations in Mirror Lake, and propose that mussel populations may be regulated by a scarcity of appropriate fish hosts in unproductive lakes. Elliptio complanata is probably not important in the metabolism or biochemistry of the Mirror Lake ecosystem. Copyright © 1981, Wiley Blackwell. All rights reserved