SMALL-SCALE DISTRIBUTION OF JUVENILE PLAICE AND FLOUNDER IN RELATION TO PREDATORY SHRIMP IN A SHALLOW SWEDISH BAY

Metamorphosed plaice and flounder were sampled in a small non-tidal nu rsery bay with a non-selective drop trap from April to August in 1991 and 1992. Post-settlement patterns were mapped in time and space and r elated to wind stress and the distribution of a potential predator Cra ngon crangon L. Both plaice and flounder had a patchy distribution at a sample scale of 1 m(2). Plaice settlement coincided with timing of o nshore winds in 1991 and 1992, while flounder settlement seemed to be unrelated. Plaice settled earlier than flounder and during the early p hase of 1-group C. crangon immigration. The first appearance of flound er occurred simultaneously with the peak biomass of predatory C. crang on. Plaice occurred in the deeper part of the bay together with C. cra ngon, while flounder preferred shallow shore waters. We propose that d ifferent temporal (plaice) and spatial (flounder) strategies have evol ved in order to minimize the risk of shrimp predation after settlement . (C) 1996 The Fisheries Society of the British Isles