Bird communities across different levels of human settlement: A comparative analysis from two northern Amazonian ecoregions

William M Hayes; Brian J O'Shea; Meshach A Pierre; Asaph Wilson; Jake E Bicknell

doi:10.1016/j.scitotenv.2023.166535

Bird communities across different levels of human settlement: A comparative analysis from two northern Amazonian ecoregions

Sci Total Environ. 2023 Dec 10:903:166535. doi: 10.1016/j.scitotenv.2023.166535. Epub 2023 Aug 25.

Authors

William M Hayes¹, Brian J O'Shea², Meshach A Pierre³, Asaph Wilson⁴, Jake E Bicknell⁵

Affiliations

¹ Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, Kent, CT2 7NR, UK. Electronic address: wmh24@kent.ac.uk.
² North Carolina Museum of Natural Sciences, 11 W Jones St, Raleigh, NC 27601, United States.
³ Tropical Conservation and Development Program, Center for Latin American Studies, University of Florida, United States.
⁴ South Rupununi Conservation Society, Shulinab, Upper Takutu-Upper Essequibo, Guyana.
⁵ Durrell Institute of Conservation and Ecology (DICE), School of Anthropology and Conservation, University of Kent, Canterbury, Kent, CT2 7NR, UK.

PMID: 37634729
DOI: 10.1016/j.scitotenv.2023.166535

Abstract

Urban ecosystems are increasingly dominating landscapes globally, so it is critical to understand the effects of human settlements on biodiversity. Bird communities are effective indicators because they are impacted by the size and expansion of human settlements, exemplified by changes in their habitat use, breeding and foraging behaviours, as well as patterns of richness and abundance. Existing studies on bird community responses to human settlements have mainly focused on single ecoregions and large cities, leaving a gap in comparative research on how differently sized human settlements affect bird communities across various ecoregions. To address this gap, we examine species richness, bird abundances and community composition in human settlements, which exhibit variable sizes, populations, landscape configurations, and overall intensity of settlement in two tropical ecoregions in Guyana, Amazonia: forest and savannah. In each ecoregion we explored how different groupings of urban tolerance in birds responded to human settlements of differing population size and building densities. Overall, we found significant differences in bird communities across the varying levels of human settlement intensity in both ecoregions, with greater differences in bird community composition in the forest ecoregion than the savannah region. In both ecoregions, species richness and abundance were highest at the medium level of settlement of human settlement. Our findings suggest that bird tolerance to human settlements varies based on ecoregion and site-level factors. In the savannah, built features may be benefitting birds from all urban tolerance levels, but they have a negative impact on less urban-tolerant species in the forest ecoregion. Our comparative analysis reveals for the first time that the impact of human settlements on avian communities in northern Amazonia varies among ecoregions, indicating that species evolved to live in a savannah may be more tolerant to human settlements than those more evolved to a forest system.

Keywords: Bird tolerance; Built features; Forest; Guyana; Savannah; Urban ecology.