Impact of land-use changes on red-legged partridge conservation in the Iberian Peninsula

Abstract

SUMMARYRed-legged partridge (Alectoris rufa) populations have significantly declined in the Iberian Peninsula (by > 50% between 1973 and 2002). This decline has been attributed to the drastic changes that have occurred in traditional agricultural landscapes, among other factors. This paper assesses the relationship between landscape change and the changes in areas favourable to partridges. The areas favourable to partridges in Andalusia (southern Spain), and the environmental and land-use factors that determined these areas, were identified for both the 1960s and the 1990s. Land-use changes were analysed both throughout the study area and for areas where favourability for partridges has either improved or worsened during recent decades. Both the location and the factors determining areas favourable to red-legged partridges have changed substantially over recent decades. In the 1960s, areas favourable to partridges were associated mainly with natural vegetation in mountainous areas, whereas, by the 1990s, favourable areas were associated with large low-lying croplands; such change may be attributable to regional land-use changes. The percentage area of the main natural vegetation variables positively correlated to partridge favourability in the 1960s model (mainly pastures and open scrubland) had decreased in areas that had become unfavourable to the species (such as mountain areas), and risen where partridge favourability increased. By the 1990s, the land area favourable to partridges had decreased byc. 10% (c. 6000 km2) in southern Spain, whereas land use unfavourable to partridges markedly increased (> 100%; an increase ofc. 3000 km2). Landscape suitable for partridges has thus become severely impoverished over recent decades in the Iberian Peninsula. Management measures aimed at improving the landscape for farmland birds should be encouraged to conserve red-legged partridge populations in southern Spain.