The species and functional diversity of birds in almond orchards, apple orchards, vineyards and eucalypt woodlots

Abstract

Agriculture is the predominant land use in Australia. Yet, there is limited knowledge of which bird species use particular agricultural crops and the implications this has for crop damage or the provision of ecosystem services. We measured species and functional diversity of bird communities in almond and apple orchards, vineyards and eucalypt woodlots. Mean bird species richness was highest in almond orchards and eucalypt woodlots and lowest in vineyards. Species diversity was highest in almond orchards, but similar among the other land uses. Bird community composition clearly differed among land uses, indicating the need to treat particular crop types as different ‘habitats’. The functional diversity of bird communities differed across land uses dependent on the functional traits and metric used to calculate diversity. Eucalypt woodlots had the highest functional richness of bird reproductive traits, whereas the highest richness of bird foraging traits was recorded in almond orchards. Importantly, increasing land-use intensification did not reduce functional diversity in a consistent way. Bird species that may damage crops or help control crop pests were common across land uses. Moreover, we recorded large numbers of the threatened eastern subspecies of the Regent Parrot (Polytelis anthopeplus monarchoides) in almond orchards. Future management of Australian agro-ecosystems should find an appropriate balance between bird conservation, limiting costs from bird damage, and promoting the provision of ecosystem services by birds.