High-elevation habitats are important for birds during the post-breeding migration period in the Alps

Mountain habitats harbour significant breeding populations of alpine bird species, yet they can also be important from a biodiversity conservation point of view outside the breeding season. High-elevations are likely important fuelling habitats for birds during the post-breeding period due to seasonal peaks in arthropod abundance being later relative to lowlands. There is no detailed study of bird communities using high-elevations in the post-breeding migration period in Europe. In this study, we recorded birds on line transects from August to October in 2021 and 2022 across an elevational gradient in the Western Italian Alps to assess how the abundance and diversity of birds varied in time and space during the autumn migration period. We detected 104 species in total, representing 22