Habitat selection of an endangered European farmland bird, the Ortolan Bunting Emberiza hortulana, in two contrasting landscapes: implications for management
Abstrakt
Effective conservation measures for any bird species across their distribution ranges require detailed knowledge of landscape-specific differences in habitat associations. The Ortolan Bunting Emberiza hortulana is a farmland bird species, which experienced massive population declines during the recent decades and has become a conservation priority in many European countries.
Thus, identification of the key habitat features is an important prerequisite for the conservation of the species. Here we investigate habitat associations of the Ortolan Bunting for the remaining breeding population of the species in the Czech Republic.
This population is remarkable by its distribution in two markedly different environments - farmland and post-mining landscapes. The main objectives of this study were to identify habitat features associated with Ortolan Bunting occurrence within the two contrasting landscapes and at two spatial scales.
Our results reveal a high degree of habitat plasticity by Ortolan Buntings in the Czech Republic which was revealed by the landscape- and scale- specific habitat associations. Habitat heterogeneity, in terms of compositional and configurational diversity, and the cover of bare ground were the most important predictors of Ortolan Bunting occurrence in both landscape types.
In farmland, the species occurrence was positively associated with shrub and woody vegetation, poppy fields and set-asides, and negatively associated with grasslands, gardens/orchards, seedlings and urban habitats. In the post-mining landscape, the cover of herb vegetation and greater slope steepness and terrain ruggedness were most important habitat features.
Ortolan Buntings in the post-mining landscape appear to avoid patches with a higher cover of shrub and woody vegetation, forests, seedlings and urban areas. We propose that conservation measures for Ortolan Buntings should focus on enhancing farmland habitat heterogeneity, but also on regulating the rate of succession in disturbed environments, such as post-mining landscapes.