Robinson, R.A., Hart, J.D., Holland, J.M. & Parrott, D. 2004. Habitat use by seed-eating birds: a scale-dependent approach. Ibis (Suppl.2) 87-98.

Abstract

The seedbank in arable farmland represents an important foraging resource for birds, particularly in grassland landscapes where alternative foraging opportunities may be scarce. We used a stepwise approach to examine the importance of seed food resources for farmland birds in winter. First, results from a large-scale experiment in which seed resources were manipulated to test the notion that birds aggregate at food resources, subject to a minimum threshold level. Secondly, a multiscale approach was used to characterize habitat use at a landscape scale and how this may inform agri-environment implementation. Overall seed resources declined sharply over the winter and were relatively low in most arable fields. Large-scale declines in the arable seedbank mean that much habitat may not be of sufficient quality to support foraging bird populations through a winter. At a landscape scale, extensive analyses of breeding season abundance show that bird abundance is most influenced by arable (i.e. seed-rich) habitat in grassland landscapes. The scale at which birds respond to habitat differs between species, and is related to the extent of between-season movements. Implementation of agri-environment schemes will need to consider both the quality of habitat and the context in which it is provided if recent declines in farmland bird populations are to be reversed.

 

Back to Publications 2004 Page