Larval immigration and subsequent settlement, abundance fluctuations, growth, and mortality of a 0-group flounder population were studied in a tidal flat area, the Balgzand, in the western Wadden Sea. Larvae entered the area from early April to early May. The first settled flounder were found about 1 mo after larval immigration started. Settled flounder were restricted to the siltier areas of the tidal flats. Growth did not seem to be food-limited within the density range observed over the

more »

... and depended only on prevailing water temperatures. The life history pattern of flounder was similar to that of plaice in the same area: year-class strength was generated in the open sea and after settlement a period of density-dependent mortality followed, most probably due to predation by crustaceans. The instantaneous mortality rate Z during summer seemed to be higher (0 08 d-l) than in plaice (0.03 dC1), probably due to a combination of higher water temperature and higher abundance of predators in summer than during the settlement of plaice in spring. No relationship between the year-class strengths of plaice and flounder was found I I I M J J A M J J A