Effects of agri-environment management for stone curlews on other biodiversity

Two-hectare unsown, tilled fallow plots put in place under agri-environment schemes for stone curlews Burhinus oedicnemus in England were surveyed for other bird species, brown hares Lepus europaeus, carabid beetles, vascular plants, butterflies and bumblebees. The results were compared with those from surveys within the crop in the same field and in neighbouring fields. This was done to test whether agri-environment management targeted at a single species also provided benefits to wider biodiversity. All groups except carabid beetles were more abundant, more likely to be recorded, or more species rich on plots than within the crop. Carabid beetle activity–density and species richness did not differ between the plot and the crop; activity–density of one functional group (predators) was lower on plots than in the crop. Six rare arable plant species were recorded, predominantly from plots, and the plots are considered to perform comparably to other agri-environment options available in England designed specifically for arable plants. One red-listed bird species of conservation concern (skylark Alauda arvensis) was more abundant on plots than in the crop, and three other red-listed species (linnet Carduelis cannabina, yellowhammer Emberiza citrinella, corn bunting E. calandra) were more likely to be recorded on plots than in the crop. A fifth (lapwing Vanellus vanellus) was almost exclusively recorded from plots, and was more likely to be recorded on plots categorised as in good condition for stone curlews. These results demonstrate that fallow plots that have been put in place for the recovery of stone curlews have considerable value for a range of other farmland biodiversity, although management for stone curlews may be detrimental to some taxa, such as carabid beetles, that are sensitive to the relatively frequent spring tillage that these plots receive.