Main content area

Selection of Breeding Cliffs by Griffon Vultures Gyps fulvus in Crete (Greece)

Xirouchakis, Stavros M., Mylonas, Moysis
Acta ornithologica 2005 v.40 no.2 pp. 155-161
altitude, breeding stock, cliffs, discriminant analysis, habitats, humans, limestone, livestock, models, multivariate analysis, nesting, principal component analysis, variance, wind direction, wintering grounds, Crete, Greece
A multivariate analysis was carried out in order to investigate the most influential habitat variables and related features in the selection of breeding cliffs by the Griffon Vulture in Crete. The species was found nesting in mid-altitude areas, close to stock-raising units, on high limestone cliffs, which were also well protected against the prevailing winds of the island. A principal components analysis, which explained 53% of the total variance of the variables examined, differentiated Griffon Vulture colonies in relation to their isolation from other colonies, accessibility to humans and proximity to food resources. In addition, a stepwise discriminant function analysis between breeding and random cliffs included the height of the cliff, its substratum, the altitude, and the distance to the stock breeding unit in a model that successfully classified 97.1% of the nesting and 88.2% of the random cliffs. In comparison to continental regions the Griffon Vulture colonies in Crete were located on higher cliffs but at a lower altitude. This fact should be attributed to the species nesting on steep coastal cliffs close to the livestock's wintering areas.