Population Structure of Mytilus Edulis L. From Lindaspollene, Western Norway

The Mytilus edulis population at Bjornoy was found to have a bimodal frequency distribution. A study of growth rings, however, showed that modes are comprised of more than one year classes which overlap each other. Distribution of size frequencies was found to exhibit an almost similar pattern throughout the year. Juvenile mussels attached to the byssus occurred throughout the year with the exception of October 1977. Late plantigrades (or juvenile mussels) varying in length from 400 to 1000 were found attached to polythene bags at the end of July 1978. Seasonal changes in the population structure were not found useful in determining the time of recruitment.