Avian communities in suspended development: disentangling mechanistic effects of changing habitat structure versus human habitation

Residential development impacts avian communities, but mechanisms behind impacts are not well understood. To elucidate mechanisms, I used suspended developments (subdivisions abandoned before completion) to represent structural habitat change from development, and compared these with forests (control) and established subdivisions (structural changes and human inhabitants) in a quasi-experimental approach. Using point counts and artificial nests, I assessed avian community composition, nest predation rates, and the predator community in 33 sites representing the three landscapes. I modeled species occupancy and abundance and nest success with landscape and local variables. Species richness increased in suspended developments and residential sites. Twenty-one species had occupancy patterns attributable to mechanisms related to habitat structure or human inhabitants. Nest predation rates and predators varied between sites but with no pattern between landscapes. Temporal effects, pets, and vegetation cover influenced nest predation. I encourage the use of suspended developments for more mechanistic studies of urban ecology.