Influence and value of different water regimes on avian species richness in arid inland Australia

Abstract

Riparian habitats in arid landscapes are recognised for their structurally diverse vegetation and diverse bird species assemblages. In the extensive semi-arid and arid centre of Australia, riparian woodland habitats are impacted by pastoral land-use which may negatively influence vegetation structure and avian species composition. However, pastoralism has promoted the establishment of artificial water bodies, so that additional riparian vegetation may occur in the landscape. In this study, we surveyed the importance of different water regimes (i.e. artificial lakes, natural waterholes, desert sites) together with their associated vegetation on avian species richness in north-western New South Wales, Australia. Our results show that bird species richness was highest at water locations, in particular at artificial lakes. Avian species richness was negatively associated with distance to water bodies, both in desert vegetation types and in the riparian vegetation type along dry creeks. Moreover, riparian habitats supported larger avian assemblages and especially those of sedentary bird species compared to the surrounding shrub-steppe landscape. This indicates that artificial water bodies may be of significance for arid zone bird species and might gain in importance with changing water availabilities due to climatic changes.