Granivorous passerines across an agricultural gradient in winter : from habitat use to community structure

Abstract

In recent decades, agricultural intensification has had profound adverse effects on farmland biodiversity, especially within the more industrialised regions of Westem Europe. Among the most severely affected groups have been granivorous birds, where decreases in over winter survival as a result of the loss of winter foraging resources, are strongly implicated in dramatic population and range declines among many species. Little detailed information exists with which to assess the impacts of agricultural intensification on granivorous birds on Irish farmland, and an intensive sampling exercise of ten granivorous passerine species was conducted in an agricultural area characterised by relatively high levels of intensification, to gauge possible national impacts. Transect censuses were undertaken over the course of two winters and two springs (Winter 2001 - Spring 2003) in the Fingal region of north County Dublin.