Intra and interspecific competition in the water shrew in the Netherlands

Abstract

In the Gagelpolder (province of Utrecht) where Neomys fodiens and Sorex araneus/coronatus live sympatrically a study was carried out into the intraspecific competition in Neomys fodiens and the interspecific competition between these two shrew species. 'The juveniles of the water shrew showed a spatial differentiation which might indicate intraspecific competition. The occurrence of this age class in sub-optimal habitat types confirmed this indication. An indication of interspecific competition between the water shrew and the common shrew was found in a temporal differentiation. The common shrew had a unimodal activity pattern with a peak in the night. Neomys fodiens, on the contrary, was captured frequently both by day and by night.