GEOGRAPHICAL VARIATION IN THE DENSITY OF THE WHITE STORK CICONIA-CICONIA IN SPAIN - INFLUENCE OF HABITAT STRUCTURE AND CLIMATE

The spatial variation in the density of white storks Ciconia ciconia i n Spain is analysed with respect to landscape and meteorological varia bles. The density of breeding pairs in 1985 was negatively correlated with surface cover of woodlands and shrublands, and positively correla ted with the area of dry or wet grasslands, reflecting food availabili ty and foraging preferences of the storks. Average minimum temperature in April-May (the first few days after hatching) was also negatively correlated with stork density, and the reproductive success in a colon y at El Tietar (Avila) was inversely correlated with the number of day s with precipitation in May. The negative influence of minimum tempera ture and precipitation on breeding density appears to be linked with t he mortality of recently born nestlings. Practical recommendations are made for the conservation of the Spanish population of white storks t hrough incentive use of pastures, meadows and 'dehesas' for cattle gra zing. Reintroduction efforts must be direct towards zones having large areas of these habitats, and mild weather.