乌鸦学会打开巢箱进行捕食

本文首次报道了大嘴乌鸦（Corvus macrorhynchos）学会打开人工巢箱捕食在里面繁殖的绿背山雀（Parus monticolus）,包括成鸟、雏鸟和卵。这种行为极有可能是通过观察人类行为而习得,但需要进一步研究来验证。     

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

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 conservation 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 artificial nest-boxes were supplied. We analyzed the composition and the configuration of the landscape at two spatial scales. We found that beside the presence of natural grasslands, heterogeneous landscape provided high quality breeding and hunting sites favorable for rollers. Even though habitat characteristics of 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 and unoccupied nest-boxes considerably overlapped, suggesting that the available habitats were not saturated. Nest-box supplementation proved to be an effective tool for rollers’ conservation in areas where natural nesting sites were limited, but prey resources were available. Consequently, the preservation of landscape heterogeneity is a key factor which should be taken into consideration in the conservation management of roller populations.