Wintering Cirl Buntings Emberiza cirlus in southwest England select cereal stubbles that follow a low-input herbicide regime

摘要

Capsule Birds selected stubbles preceded by crops with reduced pesticide inputs over those grown conventionally.Aims To compare use by wintering birds of stubbles created from cereals grown under a low-input pesticide regime with use of stubbles created from cereals grown under conventional high-input pesticide regime, in order to inform agri-environment scheme development.Methods 'Complete area search' methods were used to compare densities of birds occupying 186 stubble fields during winter 2003/04. Plant surveys were conducted on all fields at the some time as the bird surveys, while seed samples were taken from a subset of 20 special project stubbles and 20 conventional stubbles using pairwise random selection throughout the course of the fieldwork. The data were analysed using multivariate log-linear and logistic regression methods to assess the differences in bird numbers between fields, according to stubble type and other variables.Results Cirl Buntings and several other species, including Yellowhammer and Reed Bunting, used special project stubbles significantly more than conventional stubbles. Seed densities, especially those of broadleaved weeds, were higher on special project stubbles.Conclusions This work highlights the importance of continued agri-environment payments for low-input stubbles for some declining bird species, such as Cirl Buntings.