Alterations in the breeding habitats for two endangered raptor species along the Sava River basin, Croatia

Abstract

Changes in habitat suitable for breeding of two sympatric raptor species (Haliaeetus albicilla and Aquila pomarina) were analysed along one of the most important breeding sites in Croatia for both species. The habitat suitability modelling was used to assess the influence of forestry practice during 2000-2006 using the known data on nesting places along research area. The four most important variables for lesser spotted eagle were elevation, distance from the nearest pasture, vertical distance to the nearest channel network and broadleaved forest placement (second axis from the principal component analysis of the enhanced vegetation index (EVI) index of MODIS images; November-March). The variables where white-tailed eagles showed greatest shift from overall habitat characteristics in the research area were broadleaved forest (second axis from the principal component analysis of the EVI index), height above the sea level, distance from the small settlements, vertical distance to channel network - all with negative loadings. The results clearly reveal the disproportion of suitable forests for raptors that were cut down in comparison to maturation of suitable forests.

Sweet tooth is in the genes

“…With a few notable exceptions, little detailed information currently exists on habitat selection of white‐tailed eagles in coastal areas in Norway (Willgohs 1961, Nygård et al 2010). Generally, white‐tailed eagle habitat is usually connected to coastal areas, lakes, rivers, and wetlands (Radovic and Mikuska 2009, Nygård et al 2010, van Rijn et al 2010, Radovic and Jelaska 2012). Studies elsewhere have shown that white‐tailed eagles may avoid human activity (Lõhmus 2001, Radovic and Mikuska 2009).…”