Increased landscape heterogeneity supports the conservation of European rollers (Coracias garrulus) in southern Hungary

摘要

European rollers (Coracias garrulus) were almost extinct from large parts of Hungary in the 1970–1980s.However up till now their population size increased considerably, mainly due to a nature conserva-tion campaign, supplying artificial nest-boxes for breeding. We studied which factors affected rollers’occurrences at the landscape scale in southern Hungary, under natural circumstances and when artificialnest-boxes were supplied. We analyzed the composition and the configuration of the landscape at twospatial scales. We found that beside the presence of natural grasslands, heterogeneous landscape pro-vided high quality breeding and hunting sites favorable for rollers. Even though habitat characteristicsof roller territories with natural holes or nest-boxes were similar, breeding sites without artificial nest-boxes harbored higher coverage of forests and heterogeneous agricultural areas. Sites with occupied andunoccupied nest-boxes considerably overlapped, suggesting that the available habitats were not satu-rated. Nest-box supplementation proved to be an effective tool for rollers’ conservation in areas wherenatural nesting sites were limited, but prey resources were available. Consequently, the preservation oflandscape heterogeneity is a key factor which should be taken into consideration in the conservationmanagement of roller populations.