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Updated: Jun 13, 2026
07:39
A Video Surveillance System to Monitor Breeding Colonies of Common Terns (Sterna Hirundo)
Published on: July 22, 2018
Quantifying avian nest survival along an urbanization gradient using citizen- and scientist-generated data
Thomas B Ryder1, Robert Reitsma, Brian Evans
1Smithsonian Migratory Bird Center, National Zoological Park, 3001 Connecticut Avenue, Washington, D.C. 20008, USA. rydert@si.edu
Summary
Urbanization may improve bird nest survival by reducing predation, but species-specific factors and larger neighborhood scales influence outcomes. Citizen science data proved reliable for monitoring bird populations.
Area of Science:
- Urban ecology
- Avian population dynamics
- Conservation biology
Background:
- Urbanization is rapidly increasing, yet factors limiting bird populations in urban/suburban areas remain poorly understood.
- Nest survival is a critical population-level process for birds, especially in human-modified landscapes.
Purpose of the Study:
- To investigate nest survival rates of common songbirds across an urban land-use gradient in the Washington, D.C. area.
- To model the influence of urbanization (canopy cover, impervious surface), species, and observer type on nest survival.
- To assess the impact of predators and the reliability of citizen science data.
Main Methods:
- Utilized data from the Neighborhood Nestwatch citizen science project.
- Employed program MARK to model nest survival for five songbird species.
- Incorporated urbanization metrics at various spatial scales (e.g., 1000 m).
- Used artificial nests to evaluate predator impacts along the land-use gradient.
Main Results:
- Nest predation generally decreased with increasing urbanization, with species-specific variations.
- Nest survival was best explained by urbanization metrics at larger neighborhood scales.
- Citizen scientists provided nest survival estimates comparable to professional biologists.
- Artificial nest data supported findings on predator community shifts (avian vs. mammalian).
Conclusions:
- Urbanization may enhance nest survival for some songbirds, but other factors like contaminants and invasive species pose additional challenges.
- Larger spatial scales of urbanization are crucial for understanding bird population dynamics.
- Citizen science is a valuable tool for ecological research and monitoring in urban environments.
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