Urbanization and Bird Nesting Behavior: A Bibliometric Review of Research Trends and Themes (1989–2024)

Abstract

Urbanization alters habitat structure, resource availability, and exposure to anthropogenic stressors, with direct implications for bird nesting behavior and breeding success. To characterize how this topic has been studied and to identify major research themes and gaps, we conducted a bibliometric review of Scopus-indexed publications on urbanization and bird nesting behavior. Using a structured search strategy and eligibility screening, 170 documents published between 1989 and 2024 were retrieved (records from 2025 were excluded to avoid partial-year bias) and analyzed using Bibliometrix (R) and VOSviewer. Publication output increased markedly after the mid-2010s, with the United States, China, Spain, Australia, and Brazil emerging as the most productive countries. Keyword co-occurrence and content mapping revealed six dominant themes: (i) urbanization and urban ecology, (ii) nesting behavior and predation, (iii) climate and environmental change, (iv) anthropogenic impacts and adaptation, (v) reproductive ecology and parasitism, and (vi) research methods and conservation approaches. The literature is taxonomically skewed toward Passeriformes, with frequent attention to magpies, great tits, and house sparrows, while other synanthropic taxa (e.g., Hirundo rustica, Delichon urbicum, Corvus monedula, and Corvus frugilegus) are also represented but less frequently. Recent studies increasingly address artificial light at night, noise, anthropogenic nest materials, and green infrastructure, indicating a shift toward more applied and mechanistic questions. Author productivity exhibited a Lotka-type pattern, suggesting a dispersed contributor base. Overall, the field is expanding but remains geographically and taxonomically uneven; future work should extend to underrepresented regions and non-passerine taxa and emphasize standardized metrics of nesting success and urbanization intensity.