Crustacean plankton of restored Lake Starodworskie

Lake Starodworskie is a reservoir restored since the 1960s, first through artificial aeration and in the 1990s by the method of phosphorus inactivation. Studies of zooplankton were conducted in 2007–2008. The aim of the present research was to analyze and evaluate the taxonomic structure and overall abundance of the crustacean plankton of the lake. The eudominant species found were: Bosmina longirostris and Daphnia cucullata, while the dominant species included: Eudiaptomus graciloides, Diaphanosoma brachyurum and Mesocyclops leuckarti. The average annual density of Crustacea in the reservoir amounted to 329 indiv. dm−3, while the average biomass reached 5.1 mg dm−3. The abundance of indicatory species typical for eutrophic waters was smaller than recorded during previous zooplankton studies of Lake Starodworskie (average densities were: M. leuckarti – 12 indiv dm−3, T. oithonoides – 4 indiv dm−3, D. brachyurum – 14 indiv dm−3, B. longirostris – 92 indiv dm−3). The overall abundance of the zooplank ton and its structure suggest moderate eutrophy of the reservoir.