Conservation status and farmland requirements of pin-tailed sandgrouse Pterocles alchata and black-bellied sandgrouse Pterocles orientalis in Spain

Abstract

The landscape requirements are analysed and population sizes are estimated for the pin-tailed and black-bellied sandgrouse during the breeding season in peninsular Spain. The estimated populations in the 26 study zones, which comprise the main breeding areas of Spain, are c. 13,000 individual pin-tailed sandgrouse and 3500 black-bellied sandgrouse. The overall population estimate for peninsular Spain is < 14,000 pin-tailed sandgrouse and 9000–11,000 black-bellied sandgrouse. The latter figure places the species within the ‘endangered’ category in Europe. Pin-tailed sandgrouse abundance is positively correlated with the area of fallow and stubble, while black-bellied sandgrouse abundance is positively correlated with the amount of medium/long-term fallow land and the proportion of land used for dry pasture. All of these landscape variables have undergone profound changes in Spain since the 1960s due to agricultural intensification. The effects of European Union agricultural regulations on this problem are discussed. The voluntary set-aside Regulation, R. 797/85/EEC and 1094/88/CEE, has received very little acceptance. Regulation R. 1765/92/EEC, compulsory withdrawal of cropland, involves the ploughing-up of fallows and thus the loss of an important habitat for both species, especially for pin-tailed sandgrouse. Agri-environmental schemes linked to R. 2078/92/EEC potentially have the most positive effects, although it is still too early to evaluate their impact on bird populations.