We investigated the effect of two types of ditch management on the species richness and abundance of mammals at two sites in an agricultural landscape in Flevoland, The Netherlands. The first management type involved mowing both ditch slopes twice per year with a flailmower and leaving the biomass on the spot (control sections; n=3 at Tureluurweg site, n=6 at Waiboerhoeve site). Here the vegetation was short throughout winter. The second management type involved mowing the two ditch slopes in alternate years and removing the biomass (reed sections; n=3 at Tureluurweg, n=6 at Waiboerhoeve). This resulted in reed cover (Phragmites australis) at one ditch side in winter. Species richness and abundance of mammals were investigated through sightings and trapping along the ditches and in the adjacent production grasslands. Species richness and overall abundance were highest in the reed sections. Common voles (Microtus arvalis), harvest mice (Micromys minutus) and common shrews (Sorex araneus) occurred mostly in the ditches, especially in the reed sections. Only common voles were also frequently found in the grasslands but here their density was lower than along the ditches. A male-biased sex ratio in the production grasslands also indicated that these were a poor habitat for this species. Although reduced clearing frequency of the ditches benefited the common vole, outbreaks seem unlikely as long as the grasslands continue to be used intensively. Low management costs and possible application of reed biomass on arable land could also ensure a rapid integration of nature-oriented ditch management into existing farming systems.
|Publication status||Published - 2001|
- ditch banks
- species diversity
- nature conservation
- population ecology