Cities for birds, birds for cities: The urban ecology of birds across scales from global sampling to individual responses

Urbanization is transforming ecosystems worldwide, yet our ability to understand how birds persist in cities is limited by biased data and a focus on coarse occurrence patterns. This thesis examines the urban ecology of birds across scales, from a global standardized monitoring framework to city-level drivers of species prevalence and individual behavioural responses to human activity in an urban songbird. In Chapter 2, I describe and validate the Global Urban Bird Survey, a standardized acoustic monitoring protocol applied across multiple cities to generate spatially representative inventories of urban bird communities. Comparisons with eBird show that opportunistic community-science data are skewed towards greenspaces in wealthy cities, which can inflate species richness estimates, whereas stratified, randomized surveys used in the Global Urban Bird Survey provide more representative coverage and more accurately describe species richness and occurrence within cities. In Chapter 3, I use community-based surveys of bird occurrence in Ontario’s cities to relate within-species variation in prevalence to a suite of urban features, including city area, greenness, socio-economic status, and urban intensity. I show that associations with urban features differ systematically along a continuum of urban tolerance, indicating that the same city characteristics can favour urban-adapted species while disadvantaging more sensitive taxa. In Chapter 4, I focus on song sparrows (Melospiza melodia) nesting in an urban landscape to test how fine-scale variation in human activity and infrastructure around nests predicts incubation behaviour and reproductive success. Females breeding in areas with higher human activity adjust incubation rhythms, altering the frequency and duration of nest attendance bouts in ways that can coincide with elevated nest success, revealing behavioural flexibility and high tolerance of human activity as potential mechanisms of urban tolerance. Taken together, these studies demonstrate that robust assessment of avian responses to urbanization requires both improved, standardized monitoring tools and analytical approaches that accommodate species-specific, trait-mediated responses to urban environments. By integrating global sampling, cross-city analyses of urban drivers, and mechanistic field studies at the nest scale, this thesis presents a multi-scale view of urban avian ecology to help understand why some species to thrive in urban environments while so many do not.

Department dc:contributor.department

Biology

Year dc:date.issued

2026

Author dc:creator

• Preston, Paul

Advisor dc:contributor.supervisor

• Bonier, Frances

• Urban ecology
• Ornithology
• Behavioural ecology

Language dc:language.iso

eng

Handle dc:identifier.uri

https://hdl.handle.net/1974/36618

OAI identifier oai:identifier

oai:queensu.scholaris.ca:1974/36618