Does land irrigation actually reduce foraging habitat for breeding lesser kestrels? The role of crop types

The lesser kestrel is a Globally Threatened Species which large decline has been related to recent agricultural changes in European pseudo-steppes. Irrigation is considered as one of the major threats for this and other steppe birds, but the actual effects of irrigation on foraging habitat selection have been scarcely examined. We studied the selection of traditional dry cereal farming and irrigated habitats by foraging lesser kestrels during the breeding cycle, paying especial attention to possible differences among crop types. Field margins were the scarcest but the most positively selected habitat, and different stages of cereals cultivated following traditional practices were selected depending on the breeding and agriculture cycles. Effects of irrigation were dual. While irrigated maize and other crop types were avoided, alfalfa was used in proportion to its availability and later highly selected after harvesting. Moreover, field margins in irrigated land were selected in a similar way than in traditional dry farmland. Therefore, although maintaining low-intensity farming is still the main recommendation for this species, new management options arise when social pressure makes irrigation unavoidable. Further agri-environmental schemes in these circumstances should thus promote cultivation of alfalfa with a low input of biocides while avoiding maize, together with increasing field margins, to make compatible irrigation with lesser kestrel conservation.