RESOURCE PARTITIONING BETWEEN THE BANK VOLE CLETHRIONOMYS-GLAREOLUS AND THE WOOD MOUSE APODEMUS-SYLVATICUS IN WOODLAND HABITATS

Spatial and food resource use, and activity time were studied in synto pical populations of bank vole Clethrionomys glareolus and wood mouse Apodemus sylvaticus in woodland habitats. In every habitat, the two sp ecies selected different microhabitats; the abundance of thin vegetati on 2nd size and dispersion of overstorey trees were generally the vari ables that segregated the microhabitat, but no constant preferences we re shown by the two species in every habitat. Time activity rhythms we re significantly different, with the bank vole showing a multi-phase d iel activity, while the wood mouse was strictly nocturnal. However, th e diets of the two species overlapped almost completely; the wood mous e showed a higher preference for 2 seed-formed diet, while the bank vo le showed both folivore and granivore feeding habits. The differences in microhabitat selection and activity time rhythms suggested a shifti ng in resource use due to competition between the two species; the abs ence of significant differences in diet was thought to be related with the role of primary consumers played by these rodents in the woodland habitats.