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An investigation of the feeding habits and prey availability in a community of seven species of shrew (Insectivora: Soricidae) inhabiting the taiga of Central Siberia was carried out with the aim of quantifying levels of niche overlap and elucidating modes of ecological separation amongst these coexisting species. All species took a wide range of invertebrate prey, and overlap in the numbers of shared prey taxa was high, but differences in dietary composition of certain taxa reduced overlap between most species. Small species fed almost exclusively on small arthropods, mostly Araneae, Chilopoda and Coleoptera, while medium and large‐sized species took high proportions of oligochaetes. Prey were mostly taken in proportions approximately equal to their availability, although certain prey appeared to be selected. All shrews took prey in a range of sizes, and the high dietary occurrence of small invertebrates reflected their availability and high encounter rate in field samples. Dietary occurrence of small prey was negatively correlated, and large prey positively correlated, with body size of shrew. Smaller shrews were predominantly ground‐surface foragers while larger species were more subterranean, with body size and dietary occurrence of soil prey being positively correlated. Differences in prey size and foraging mode reduced niche overlap between shrew species of widely differing sizes. Each shrew species did not occupy a separate, well‐defined food niche. Instead, the community was sub‐divided into three functional groups: large and small species which tended towards specialization with relatively low levels of overlap, and intermediate, generalist species with higher levels of overlap.

Prey selection, food niche overlap and resource partitioning were investigated in semi‐aquatic Neomys fodiens and Neomys anomalus and terrestrial Sorex araneus and Sorex minutus coexisting in marshland in Białowieża Forest, eastern Poland. Evidence of prey selectivity was found but high levels of overlap, particularly in prey size, reflected the abundance of invertebrates in field samples. Despite similarities in diets between all four species, evidence of niche differentiation was found in terms of foraging mode and prey composition. Neomys ate predominantly terrestrial prey but 20% of prey of N. fodiens was aquatic (compared with 11% in N. anomalus), with Asellus being the dominant aquatic prey. Sorex shrews were exclusively terrestrial in foraging mode. All species ate predominantly small prey (≤5 mm) and these were most abundant in field samples, but small prey were most important for S. minutus. Pairwise comparisons suggested that the most important promoter of resource partitioning was body size, indicating different foraging modes. Food niche overlap was least between species most dissimilar in size. The tiny S. minutus was predominantly an epigeal forager on small Araneae, Opiliones and Coleoptera; the medium‐sized S. araneus fed extensively on Lumbricidae and Coleoptera; and the large, semi‐aquatic Neomys fed on different amounts of freshwater prey in addition to terrestrial prey. Our results support the prediction that microhabitat selection among these species indicates differentiation in foraging mode.

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