Crustacean communities as food resources for fish in shallow Polesie lakes with contrasting development of submerged macrophytes

The aim of the research was to evaluate crustacean forage resources for fish in five shallow lakes varied in respect to species richness and coverage of submerged macrophytes, and thus representing different alternative stable states. The results revealed that lakes with a high or moderate abundance of macrophytes and moderate visibility (macrophyte-dominated Lake Rotcze, phytoplankton-macrophyte dominated lakes Sumin and Głębokie) displayed reach crustacean forage base for fish. Poor feeding conditions were found in two extremely different lakes: turbid phytoplankton-dominated Lake Syczyńskie devoid of macrophytes, and heavily vegetated, clear-water macrophyte-dominated Lake Kleszczów. Possible reasons for these differences are discussed.