Density, sizes and ages of Mytilus edulis, and number of symbionts at three sites in the White sea

Mussels Mytilus edulis were collected from three tidal levels (three samples of 20-23 mussels from 1*1 m quadrates at each level) at three sites at the White sea in summer 2013. Their shell lengths and ages were measured. All the symbionts found in the mussel's tissues and mantle cavities were counted. The first dataset contains the number total of mussels >5mm per 1 square meter at each level at each site. The second dataset includes mussel lengths, ages and numbers of organisms found in association with the mussels