Martinez-Lanfranco, J.A., F.J. Vilella, and D.A. Miller. 2022. Avian community response to a novel environment: commercial forestry in the Campos grasslands of South America. Forest Ecology and Management 503:119765
Abstract
Establishing commercial tree plantations in native grassland ecosystems introduces a fundamentally different structural and functional vegetation cover type, with expected implications for biodiversity. To better understand biodiversity responses to afforestation, we conducted a resource-use study, with birds as a focal group, during the 2013–2014 breeding season in the Northern Campos grasslands of Uruguay. We sampled birds in native environments and plantations of loblolly pine (Pinus taeda) and flooded gum (Eucalyptus grandis) at different rotation stages. We recorded 103 species during 1,573 10-min visits to 570 stratified sampling units. Grasslands and forests exhibited greater diversity and had greater variability in species composition than structurally homogeneous plantations. Avian communities in plantations had distinct species combinations and relative abundances not found in native conditions. Avian communities in older plantations were more similar to native forests while those of newly-planted stands were more like grasslands. However, communities in plantations were dominated by habitat generalists and some forest-dependent species, with negligible use by grassland specialist birds. Our results suggest the best conservation opportunities for grassland-dependent birds in afforested systems may depend on targeting larger and diverse landscape-level measures rather than stand-level management practices. Albeit our research constituted a comprehensive assessment of bird taxonomic alpha and beta diversity, research on complementary diversity facets and multi-scale resource selection and demographic studies are needed to better understand opportunities for conserving and managing grassland birds in afforested landscapes.