Damping in the Hinge of the Scallop Placopecten Magellanicus

Abstract
The family Pectinaceae are the only bivalves that have been well documented as swimmers (DeMont, 1992), although Ensis minor has been observed to swim (McMahon and McMahon, 1983). The behaviour was once regarded only as an escape response (Gade, 1981; McMahon and McMahon, 1983), but some studies suggest seasonal migrations are involved (Gruffydd, 1976; DeMont, 1990). DeMont (1990) suggests that they swim at the natural frequency of the shell-hinge system for more efficient use of energy.