Systematic Raptor Monitoring as conservation tool: 12 year results in the light of landscape changes in Dadia-Lefkimi-Soufli National Park

Abstract

Dadia-Lefkimi-Soufli National Park forms part of the Natura 2000 network in a region of Greece and represents one of the most diverse landscapes for raptors (birds of prey) breeding in Europe. It is adjacent to Bulgaria and Turkey and is a renowned biodiversity hotspot. WWF Greece established a Systematic Raptor Monitoring scheme in this area in 2001.This study summarises the results of the first 12 years of monitoring in the National Park. Overall, 25 to 27 raptor species were recorded by pooling data, of which20 species reproduced in the National Park. Raptors with continuous presence in the National Park exhibited stable, species-specific inter-annual variation. An average of 348±15.4 raptor territories were distributed throughout the National Park for all species. The Common buzzard (Buteo buteo) and the Short-toed eagle (Circaetus gallicus) were the most common species year-round, followed by the Lesser-spotted eagle (Clanga pomarina) and Booted eagle (Aquila pennata). The Long-legged buzzard (Buteo rufinus), Honey buzzard (Pernis apivorus) and Egyptian vulture (Neophron percnopterus) exhibited a noticeable drop in population numbers over the study period. A significant new entry was the re-appearance of the White-tailed eagle (Haliaeetus albicilla), which was recorded breeding again in the region after a 21-year absence. Species trends, along with their ecological traits, are discussed with respect to landscape changes in Dadia NP and minimum viable population and territory thresholds are proposed to outline essential conservation issues. Although a multi-year balance of the total number of occupied territories for all species was recorded, the number of common species increased compared to specialist species which had smaller, declining populations. The abandoning of traditional livestock farming, which induces an increase in closed-canopy forest coverage, might have led to the decline of the Lesser-spotted eagle, Long-legged buzzard and Honey buzzard numbers. Additional pressure is added from specialist forest dwelling raptors which are favoured by this change in habitat. The results of this study are expected to provide useful insights to facilitate conservation and management decisions about raptors and their habitat in this region.