Managing set-aside for field voles (Microtus agrestis)

Set-aside is a potentially important habitat for field voles, (Microtus agrestis), populations of which may have declined in lowland Britain. We hypothesized that field vole abundance would increase with the length of time set-aside was left in situ. To test this we monitored development of field vole populations in the first 2 years after set-aside establishment, and on older set-aside we related abundance to set-aside age and vegetative characteristics. Voles were not recorded on set-aside until 9 months after establishment, and populations only began to increase after nearly 2 years. In set-aside fields 2-9 years old, vole abundances were not related to age, but increased with the proportion of grasses and litter in the sward. Management practices such as sowing with a grass seed mix, mowing at least once annually and leaving set-aside in place for > 2 years are likely to benefit field voles. (C) 2000 Elsevier Science Ltd.