Further Developments of Macrozoobenthos in Lübeck Bay, Following Recolonisation in 1980/81

The macrozoobenthos in Lübeck Bay (West Baltic) was investigated from 1982 to 1985. The bottom water layer is characterised by oxygen deficiency or even presence of H2S at depths greater than 20 m in late summer and autumn, when the benthic fauna lacks diversity and consists only of Halicryptus spinulosus, Polydora ciliata and Diastylis rathkei. The influx of oxygen‐rich water into the region is followed by rapid colonisation by opportunistic species (Capitella capitata, Polydora ciliata) which are joined by predacious species, such as Harmothoë sarsi, Halicryptus spinulosus, and Anaitides maculata. Bivalve larvae are carried in by the current. It is assumed that, if the hydrographic conditions remain uniformly favourable, damaged regions will be recolonised after a year by drifting larvae and, for a few species, by adult immigration.