The reproductive cycle and physiological ecology of the mussel Mytilus edulis in a subarctic, non-estuarine environment

Abstract

Mytilus edulis L. occupies a habitat in eastern Newfoundland, Canada, which is characterised by low temperatures and a lower concentration of particles in suspension than is found in estuarine locations. Gametogenesis occurs in the spring, and energy reserves from the previous year are not utilised in the synthesis of gametes. Oxygen uptake is not elevated during the winter, in contrast to most European populations, which undergo gamete development at that time. There is little seasonal variation in clearance rate. This may be attributable in part to the absence of the high particulate load which has been shown to depress feeding activity in some estuarine populations. Energy balance is positive at all times of the year, and conversion efficiency is high, suggesting that conditions are favourable. A number of physiological comparisons are made between Newfoundland mussels and those from European waters.