Intra- and interspecific density dependence in the survival and recruitment of grey-sided (Clethrinomys rufocanus) and bank voles (C. glareolus)

Habitat use patterns by sympatric bank (Clethrionomys glareolus) and grey-sided (Clethrionomys rufocanus) voles indicate interspecific competition between the two species, with grey-sided voles being the superior competitor. Data from a four-year study of two populations of bank and grey-sided voles were analysed with capture-recapture models to investigate the effects of competition on winter and summer demographic parameters. In summer survival of bank voles was positively correlated with bank vole density, whereas recruitment was negatively correlated to bank vole density. No evidence was found for intraspecific density-dependence in the demographic parameters of grey-sided voles, although there was a tendency towards a negative intraspecific effect on winter survival. There were no detected effects of interspecific competition on the demography of either vole species.