Territory distribution and foraging patterns of cirl buntings (Emberiza cirlus) breeding in the UK

摘要

A recent recovery in cirl bunting (Emberiza cirlus) numbers in the UK has been aided by deployment of prescriptions for environmentally friendly management of farmland under the Countryside Stewardship Scheme. However, the species' range has not expanded and the population is increasingly under threat from habitat loss due to built development. The UK Biodiversity Action Plan calls for re-establishment of populations outside the current range in order to ensure a wider geographical spread of this species. This study examined territory distribution and foraging patterns of cirl buntings in relation to habitat variables in order to inform the process of site protection and site selection for a possible translocation programme. Cirl bunting territories were positively associated with rough grassland, non-linear scrub and habitat richness, and intensive permanent pasture was avoided. Resampling methods showed that rough grassland was used significantly more than improved pasture as a foraging habitat and that both rough grass and cereals were used more than other arable crops. The results emphasise the importance of protection of unimproved pastures in 'green field' sites and will help quantify the potential carrying capacity of candidate `receptor' sites.