| Variations in demographic parameters between intertidal populations of Nereis virens and Nephtys caeca were studied. These polychaetes are major component of the Macoma balthica community in the Lower St. Lawrence estuary (Quebec, Canada). We compared spatial distribution between differently oriented shores in a small geographic area. Our results revealed an interpopulation variability that appears to be dependent on hydrodynamical processes, edaphic parameters and biological interactions. In north and northeast oriented flats, the higher densities of young individuals of Nereis virens are found in the higher tidal levels where we observed larval recruitment and the highest organic matter contents. On the other hand, the lower densities of adult worms are... |
