Studies on parasitism in zooplankton and periphyton assemblages were carried out on samples of water collected from Lakes Płociczno and Płociowe in the Drawa National Park in 2008-2011. Occurrence of the fungal mycobiotal and protozoan parasites of invertebrates was recorded in both lakes. Parasitism of Chydorus sp. (Cladocera) by Saprolegnia sp. occurred on 0.8% of individuals of the host population, of Brachionus calyciflorus (Rotifera) by Microsporidium sp. on 1.2% of the host population, and of Nematoda members by Pythium sp. on 5% of the host population. Parasites were recorded only in springtime.
We present results of our preliminary research on species diversity, dominance structure, and phenology of bees (Apiformes) in the Drawa National Park (NW Poland). In total, 118 species of Apiformes were recorded there, which accounted for 25.5% of the Polish bee fauna. The park is dominated by woodland, so major species are Bombus lucorum (23.6%) and Andrena lapponica (8.8%). Those species, on some sites, accounted for over 20% or even over 40% of the total catch.