Although the study of bird acoustic communities has great potential in long-term monitoring and conservation, their assembly and dynamics remain poorly understood. Grassland habitats in South Asia comprise distinct biomes with unique avifauna, presenting an opportunity to address how community-level patterns in acoustic signal space arise. Similarity in signal space of different grassland bird assemblages may result from phylogenetic similarity, or because different bird groups partition the acoustic resource, resulting in convergent distributions in signal space. Here, we quantify the composition, signal space and phylogenetic diversity of bird acoustic communities from dry semiarid grasslands of northwest India and wet floodplain grasslands of northeast India, two major South Asian grassland biomes. We find that acoustic communities occupying these distinct biomes exhibit convergent, overdispersed distributions in signal space. However, dry grasslands exhibit higher phylogenetic diversity, and the two communities are not phylogenetically similar. The Sylvioidea encompasses half the species in the wet grassland acoustic community, with an expanded signal space compared to the dry grasslands. We therefore hypothesize that different clades colonizing grasslands partition the acoustic resource, resulting in convergent community structure across biomes. Many of these birds are threatened, and acoustic monitoring will support conservation measures in these imperiled, poorly-studied habitats. This article has an associated First Person interview with the first author of the paper.
Bibliographical noteFunding Information:
A.K. is funded by an INSPIRE Faculty Award from the Department of Science and Technology, Ministry of Science and Technology, India and an Early Career Research Award (ECR/2017/001527) from the Science and Engineering Research Board (SERB), Government of India. S.L. received funding for this project from an Oriental Bird Club Conservation Grant, equipment support from Idea Wild, and a Rufford Foundation Small Grant (awarded to Ram Mohan, in collaboration with S.L. who sampled birds).
© 2021. Published by The Company of Biologists Ltd.
- Acoustic community
- Community bioacoustics
- Signal space
PubMed: MeSH publication types
- Journal Article
- Research Support, Non-U.S. Gov't