EVALUATION OF METHODS TO ESTIMATE FIELD VOLE MICROTUS-AGRESTIS ABUNDANCE IN UPLAND HABITATS

Field vole abundance was assessed on a range of upland habitats in spr ing and autumn, using live-trapping, snap-trapping and vole sign index methods. Three estimates of vole numbers were derived from live-trapp ing, five from snap-trapping and one from vole signs. Estimates were c ompared using a correlation matrix in order to establish the most accu rate and consistent method. Snap-trapping for five nights provided eno ugh information to calculate vole density, though the method was time consuming. Vole abundance indices derived from two nights' snap-trappi ng were significantly correlated with indices from five nights' trappi ng. Live-trapping and vole sign index were discounted as methods for t his study area, as both proved unreliable.