Regional and farm system drivers of avian biodiversity within agriculture ecosystems

Farm-wide bird surveys were carried out on 119 grass-based farms located in three separate regions in Ireland during the winter and breeding seasons. Data relating to livestock production system (dairy or non-dairy) and participation in the Irish agrienvironment scheme (AES) at the time, the Rural Environmental Protection Scheme, were collected. GLMMs were used to establish the factors influencing bird populations during the winter and breeding season. Region and farming system had significant effects on avian biodiversity and there were frequently greater numbers on more intensively managed dairy farms, compared with less intensive non-dairy farms. AES participation had no significant effect on bird populations. Our findings demonstrate a clear influence of region and farm system on avian biodiversity, and suggest that the greater resource availability in more intensive farm systems may actually be beneficial for certain components of farmland biodiversity.