Grassland and patch scale diversity in supporting avian diversity and potential ecosystem services

Abstract

The composition and structure of vineyard landscapes significantly affect bird communities and the ecosystem services they provide in agriculture. In vineyards, insectivorous birds can help control insect pests, offering a valuable service. However, fruit- and seed-eating birds may cause crop losses by damaging or consuming grapes, with the impact varying by season. We conducted avian point counts and landscape analysis on 40 vineyard plots in the German wine regions of Rhinehesse and Rheingau in 2020 and 2021. We test the hypothesis that a heterogeneous viticultural landscape supports a diverse bird community rich in ecosystem services during both the breeding and non-breeding seasons, thus supporting viticultural efforts. For all response variables, our models showed better explanatory power and model fit at the patch and local scale (100 and 250 m) than at the landscape scale (500 m). Grassland and Shannon Diversity Index emerged as consistent positive predictors of species richness and diversity, while arable land had negative effects, particularly at patch scale. The Shannon Diversity Index consistently emerged as a critical positive driver of insectivore communities, highlighting the importance of landscape heterogeneity. Conversely, farmland had negative effects on species richness and diversity for insectivorous birds across seasons. Our results suggest that maintaining grasslands and promoting landscape heterogeneity are essential for supporting diverse avian communities in vineyard ecosystems, which have the potential to provide critical ecosystem services to winegrowers.