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In this study, we compared the ostracod species diversity in selected inland-water habitats of Lapland and Poland, and assessed the relationships between ostracod occurrence and abiotic environmental variables. In total, 41 species were collected, of which only 15 species were found in Lapland, as compared with 35 in Poland. Almost all species collected from the Lapland sites were eurybiontic and no clear differences were found between ostracod assemblages inhabiting different habitat types. We hypothesize that this homogeneity might be a consequence of the raised water level during the springtime snow melt, temporarily connecting various waterbodies. The main factors limiting distribution of ostracod species in Lapland appeared to be low pH and low ionic content of water. In Poland,predominantly stenobiontic species were observed. In temporary waters and peat-bogs of this area useful indicator species were identified.
In Oscine species, changes in songs are age-dependent: some species do not change their singing repertoires after a short sensitive period, whereas others may include new songs throughout their lives. In many cases, changes in singing repertoires are more pronounced between the first and second years of life. I describe changes in song composition from one year to the next in 23 pied-flycatcher males, which differed in breeding plumage coloration. Eight yearling birds showed profound between-season syllable repertoire turnover whereas seven yearlings and eight older males retained their previous song composition. Males with profound changes in their repertoire were significantly paler, arrived later and had smaller first-year repertoires than other males. Although additional studies are needed to clarify the relationship between these factors, it seems plausible that dark- and pale-coloured pied-flycatcher males have different patterns of between-season repertoire turnover: pale males change their syllable repertoire sufficiently between the first and second years of life but not thereafter, whereas dark males develop a rather stabilised repertoire by the first year of life. This agrees with the finding that pale and dark birds exhibit different breeding strategies.
In amphibians, most species are female-biased sexually dimorphic and such dimorphism is often accompanied by intersexual differences in prey composition. While many aspects of foraging ecology have been studied in this group, intersexual differences have rarely been described. We examined dietary composition of male and female Alpine newts (Mesotriton alpestris) from two localities in the Czech Republic during the entire breeding period by stomach flushing, lsopoda, Cladocera, Rana eggs were the most, important prey. About 16% of newts did not. contain prey items. At studied localities, females were about 15% larger than males. Snout—vent length (SVL) of newts was related to the mass of consumed prey, but not its number and diversity. Analyzing the residuals from the relationships between SVL and prey characteristics, we found the effect of sex on all observed prey variables — the females consumed more prey items, more diverse prey and also in greater mass than did the males.
Spatial variation in wintering bird communities in different types of urban residential areas is poorly understood. The objective of tills study was to find out which bird species from the regional species pool are able to inhabit residential areas, whether bird communities in different types of residential area differ from one another, and what are the factors affecting birds. We conducted our study in five apartment-building areas, five family-house areas, and five villages in northern Finland by using the single-visit study plot method during five winters, i.e. 1998/1999–2003/2004. Oldgrowth-forest-specialist species, in particular, avoided residential areas, whereas the other species appeared to benefit from residential development. The species richness, the total number of individuals, and the abundance of most of the species were higher in the family-house areas and in villages than in apartment-building areas. The proportion of individuals belonging to resident species was higher in the apartment-building areas than in the other habitats, whereas the proportion of individuals belonging to feeding-table species was higher in the villages than in the other habitats. The species richness and the total number of individuals increased with the increasing number of feeding tables and decreased with increasingly larger proportions of apartment buildings within the study plot. Parus montanus, P. major, P. caeruleus, Passer domesticus, and Carduelis flammea benefitted from feeding tables. Our study demonstrated that carefully planned winter feeding programmes can enhance the wintering possibilities for birds, and thus promote the biodiversity in urban ecosystems at northern latitudes.