Effects of sheep grazing on abundance and predators of field vole (Microtus agrestis) in upland Britain
نویسنده
چکیده
A technique using fresh feeding signs as an index of density was validated and used to survey the effects of sheep grazing on vole population densities in four upland habitats in the northern Peak District National Park, UK. In grazed areas Molinia caerulea grasslands supported most voles, Nardus stricta grasslands supported fewer and Eriophorum vaginatum and Calluna vulgaris-dominated areas supported least. There were highly significant negative relationships between vole sign density and sheep numbers in these habitats. Where sheep were excluded, these same habitats had between three and nine times higher sign densities, corresponding to between 1.5 and
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