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Urbanization has a homogenizing effect on biodiversity and leads to communities with fewer native species and lower conservation value. However, few studies have explored whether or how land management by urban residents can ameliorate the deleterious effects of this homogenization on species composition. We tested the effects of local (land management) and neighborhood-scale (impervious surface and tree canopy cover) features on breeding bird diversity in six US metropolitan areas that differ in regional species pools and climate. We used a Bayesian multiregion community model to assess differences in species richness, functional guild richness, community turnover, population vulnerability, and public interest in each bird community in six land management types: two natural area park types (separate and adjacent to residential areas), two yard types with conservation features (wildlife-certified and water conservation) and two lawn-dominated yard types (high- and low-fertilizer application), and surrounding neighborhood-scale features. Species richness was higher in yards compared with parks; however, parks supported communities with high conservation scores while yards supported species of high public interest. Bird communities in all land management types were composed of primarily native species. Within yard types, species richness was strongly and positively associated with neighborhood-scale tree canopy cover and negatively associated with impervious surface. At a continental scale, community turnover between cities was lowest in yards and highest in parks. Within cities, however, turnover was lowest in high-fertilizer yards and highest in wildlife-certified yards and parks. Our results demonstrate that, across regions, preserving natural areas, minimizing impervious surfaces and increasing tree canopy are essential strategies to conserve regionally important species. However, yards, especially those managed for wildlife support diverse, heterogeneous bird communities with high public interest and potential to support species of conservation concern. Management approaches that include the preservation of protected parks, encourage wildlife-friendly yards and acknowledge how public interest in local birds can advance successful conservation in American residential landscapes.
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This content will become publicly available on June 1, 2026
Urbanization and climate drive long‐term bird community trends across a desert city ecosystem
Abstract Sustaining biodiversity requires measuring the interacting spatial and temporal processes by which environmental factors shape wildlife community assembly. Declines in bird communities due to urban development and changing climate conditions are widely documented. However, the combined impacts of multiple environmental stressors on biodiversity remain unclear, especially in urbanized desert ecosystems. This is largely due to a lack of data at the scales necessary for predicting the consequences of environmental change for diverse species and functional groups, particularly those that provide ecosystem services such as seed dispersal, pest control, and pollination. Trends in the prevalence and diversity of different functional groups contribute to understanding how changes in bird communities impact well‐being through the lens of ecosystem services. Across the rapidly developing drylands of the metropolitan Phoenix, Arizona, USA, we ask the following question: How have inter‐ and intra‐annual landscape changes associated with urbanization and climate shaped the dynamic characteristics of bird communities, specifically the abundance and richness of species and their functional groups? We analyzed long‐term drivers of bird communities by combining a two‐decade, multi‐season spatial dataset of environmental conditions (urbanization, vegetation, temperature, etc.) with biotic data (species richness and abundance) collected seasonally during the same time periods (winter and spring; 2001–2016). Results show that increased impervious surface area and land surface temperature were negatively associated with overall bird abundance and species richness across the study period, especially during winter. However, these relationships varied among functional groups, with potentially mixed outcomes for ecosystem services and disservices provided by urban biodiversity. By improving knowledge of long‐term trends in multiple environmental drivers that shape wildlife community dynamics, these results facilitate effective evaluation of how landscape management practices in drylands influence the outcomes of evolving human‐wildlife relationships.
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- Award ID(s):
- 2416164
- PAR ID:
- 10617957
- Publisher / Repository:
- Ecological Society of America
- Date Published:
- Journal Name:
- Ecological Applications
- Volume:
- 35
- Issue:
- 4
- ISSN:
- 1051-0761
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract Urbanization has a homogenizing effect on biodiversity and leads to communities with fewer native species and lower conservation value. However, few studies have explored whether or how land management by urban residents can ameliorate the deleterious effects of this homogenization on species composition. We tested the effects of local (land management) and neighborhood‐scale (impervious surface and tree canopy cover) features on breeding bird diversity in six US metropolitan areas that differ in regional species pools and climate. We used a Bayesian multiregion community model to assess differences in species richness, functional guild richness, community turnover, population vulnerability, and public interest in each bird community in six land management types: two natural area park types (separate and adjacent to residential areas), two yard types with conservation features (wildlife‐certified and water conservation) and two lawn‐dominated yard types (high‐ and low‐fertilizer application), and surrounding neighborhood‐scale features. Species richness was higher in yards compared with parks; however, parks supported communities with high conservation scores while yards supported species of high public interest. Bird communities in all land management types were composed of primarily native species. Within yard types, species richness was strongly and positively associated with neighborhood‐scale tree canopy cover and negatively associated with impervious surface. At a continental scale, community turnover between cities was lowest in yards and highest in parks. Within cities, however, turnover was lowest in high‐fertilizer yards and highest in wildlife‐certified yards and parks. Our results demonstrate that, across regions, preserving natural areas, minimizing impervious surfaces and increasing tree canopy are essential strategies to conserve regionally important species. However, yards, especially those managed for wildlife support diverse, heterogeneous bird communities with high public interest and potential to support species of conservation concern. Management approaches that include the preservation of protected parks, encourage wildlife‐friendly yards and acknowledge how public interest in local birds can advance successful conservation in American residential landscapes.more » « less
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