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With 4 figures in the text)The habitat occurrence and invertebrate prey distribution of nine species of shrew in the midtaiga of central Siberia were investigated. Species richness ranged from 4-9 shrews per habitat. Sorrx araneus and S. cueculiens were numerically dominant in all seven habitats (44 and 36% of the total catch, respectively) while Sorex minutus, S. tundrensis, S. isodon, and S. roboratus each constituted 4-6% and Sores minutissimus, S. dapharnodon, and Neomys,fodiens were rare ( < 1 YO each). There was no overall correlation between abundance of shrews and invertebrate prey, but flood-plain habitats supported the greatest abundance and species richness of shrews, and high density and biomass of prey. Oligochaete-eating shrews were twice as numerous here as in other habitats, coincident with high abundance of oligochaetes. The large, earthwonn-feeding Sorex rohoraru.r occurred only here. The more acid, typical taiga habitats had lower adundance and species richness of shrews. They had the lowest density and biomass of prey, particularly oligochaetes, and far fewer ohgochaete-eating shrews. The relative paucity of shrews in bushmeadow habitats, despite abundant prey, implied that habitat structure influences shrew distribution. Differential numbers of certain species in the presence or absence of larger congeners also suggested that interspecific competitive effects influence habitat selection by shrews. The high species richness of shrews here in the mid-taiga may be accounted for by the heterogeneous nature of the constituent habitats which provide niches for small and large species of shrew with a range of feeding habits.

The feeding habits and foraging modes of six species of shrew (Insectivora, Soricidae) coexisting in the forests of the Russian Far East were investigated in order to quantify levels of niche overlap and elucidate the role of body size in ecological separation. Overlap in numbers of shared prey taxa was high and Lithobiomorpha, one of the most abundant macro-invertebrates in ®eld samples, was a major prey item of all species. The composition of different prey taxa in the diet of Sorex unguiculatus and the abundance of these taxa in ®eld samples were positively correlated. Major differences in dietary composition and foraging mode re¯ected body size of shrews. While the niches of individual species were not exclusive, small species fed only on arthropods, were epigeal, and had relatively narrow niche breadths. Large species fed extensively on lumbricids and other soil-dwelling invertebrates, and were hypogeal. There were signi®cant negative correlations between niche overlap in terms of prey composition, prey size and prey location, and increasing body-length ratios in pair-wise comparisons. Combined niche overlap was reduced with increasing divergence of body size. Adjacent species-pairs in the size series had a mean combined niche overlap of 88% compared with non-adjacent pairs of 67%. The most signi®cant areas of ecological separation between species as a function of body size were in the dietary occurrence of small versus large prey and in the foraging mode (epigeal versus hypogeal). These ®ndings con®rm that body size has an important role in effecting ecological separation in multi-species communities where a high degree of morphological and ecological similarity occurs between members.

The article discusses the evolution and current state of transparency of environmental performance data in the Russian Oil and Gas sector. We build upon our first‐hand experience in a transparent, publicly available information and third‐party‐verified rating system. Based on 2014–16 successive annual ratings, we conclude that implementing “soft” responsibility mechanisms can improve environmental responsibility standards and transparency in the oil and gas industry. At the same time, in terms of improving environmental performance of oil and gas companies it is reasonable to assume an emerging trend. Its full realization will require (1) longer rating time, including that for public exposure to misleading environmental performance information and the use of poorly verified nonfinancial reporting; (2) application of independent analysis of satellite monitoring information to the professional audit and public verification of nonfinancial reporting; and (3) sophistication of guidelines for professional audit and public verification of nonfinancial reports.