Long-term dynamics of common species of polychaetes in fouling communities of the White Sea

Based on the data from long-term observations on the development of fouling communities of mussel culture farms in the White Sea, an analysis of dynamics of population density of common polychaete species was carried out. The expansion of the polychaete Lepidonotus squamatus for the past 9 years was recorded. Cyclic variations of population density were revealed practically in all studied species. The duration of the period of these cycles varied from 7–8 years (L. squamatus and Amphitrite cirrata), 11–14 years (Nereis pelagica, Harmothoe imbricata, Eulalia viridis, Neoamphitrite figulus) and even about 20 years (Nereimyra punctata and Capitella capitata). Observable periodic variations in the abundance of polychaetes apparently were not related to long-term fluctuations of water temperature.