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The paper presents results of a study conducted in Ińsko Landscape Park in the years 2002 and 2003. The study has confirmed the occurrence of 11 amphibian species, which coincides with results obtained previously by other researchers. The presence of two amphibian species from the “Red List of Threatened Species in Poland”, namely Triturus cristatus and Bombina bombina has been confirmed. Another important result of the study is the confirmation of the occurrence of Bufo calamita in the studied area. Finally, the paper presents the dynamics of occurrence of selected species.
The presence of Dytiscus latissimus L. was discovered in the course of the studies on invertebrates from the Ińsko Lake. This beetle species had not been reported from that region of the country before. Not only is it a rare and protected species in Poland, but it is also featured in the Red List of Threatened species.
The authors investigated of the mycoflora developing on the eggs of Miedwie whitefish (Coregonus lavaretus maraena). 32 aquatic zoosporic fungus species developed on the eggs, including 24 of the order Saprolegniales and 8 of the Peronosporales.
A new locality of Temnothorax affinis (Mayr), a Euro-Caucasian xerothermophilous dendrobiotic ant species rare in Central Europe, is reported from Poland; until recently it was regarded as probably extinct in Poland. Single workers were collected from an oak trunk of an old oak in the Cedynia Landscape Park (Pomeranian Lake District, north-western Poland). This locality is one of northernmost known sites of T. affinis.
Background. Vendace, Coregonus albula (L.), is one of the most valuable components of Polish lake ichthyofauna. The vendace from different lakes differ in their principal vital characteristics (such as growth rate etc.) and it is therefore crucial to determine those characteristics from different throphic types of lakes in order to implement proper measures of fisheries management for those coregonids. The aim of the present paper was therefore to learn principal biological features of vendace populations representing three different Pomeranian lakes. Materials and Methods. Comparative biological studies were carried out on 136 vendace from Pełcz Wielki Lake, 304 from Bytyń Wielki Lake, and 62 from Wełtyń Lake (Pomerania Lakeland) collected within 2002-2003. The age and growth rate of the fish were determined from scales. Fulton′s condition factor and the total length-weight relation were used to determine fish condition. Results. Gillnet selectivity influenced fish age structure and size. For example, among 502 vendace obtained, in total, from the three lakes, 75.7% (380 specimens) were 2+. The results of back-calculations and the parameters of von Bertalanffy′s growth equation revealed distinct disproportions in the total length in individual age groups (Pełcz Wielki Lake: Lt = 213.22[1 - e-0.49576(1 + 1.055013)]; Bytyń Wielki Lake: Lt = 219.17[1 - e-0.733553(1 + 0.040147)]; Wełtyń Lake: Lt = 255.08[1 - e-0.571108(1 + 0.023036)]) Slower length- and weight growth rates were observed in the fish from Pełcz Wielki Lake. Conclusion. The growth rates, determined using back-calculations, were different for the vendace populations representing lakes Pełcz Wielki, Bytyń Wielki, and Wełtyń in the sequential years of fish lives. The fish from Wełtyń Lake were characterized by average growth, whilst the fish from the remaining reservoirs were characterized by slow or very slow growth. The lower condition values and growth rates from Pełcz Wielki Lake were probably the result of poor environmental conditions in this body of water.
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