Trends of autumn counts at Iberian migration bottlenecks as a tool for monitoring continental populations of soaring birds in Europe

摘要: Migration monitoring may allow us to detect population trends over large geographic areas because the pattern of change in migrant counts be expected follow size. We analysed recent regional European migratory soaring birds from rates migration Strait Gibraltar (Spain) during years (1999–2013). An additional bottleneck (Organbidexka, France) within same route and period was also considered. estimated count by fitting a log-generalized linear model time series each species counts. The Organbidexka were used test consistency observed Gibraltar. White Black Storks, Kites, Short-toed Booted Eagles as well Egyptian Vultures showed increase throughout 15-year period. In contrast, Honey Buzzard numbers remained stable. Trends highly consistent with those recorded Organbidexka. suggest that larger slopes for when compared reflect an increasing tendency these overwinter southern Europe. A combination complementary data sets collected at different sites European–African flyway system become fundamental tool investigation patterns changes all