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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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No fry zones: How restaurant distribution and abundance influence avian communities in the Phoenix, AZ metropolitan area
Urbanization is one of the most widespread and extreme examples of habitat alteration. As humans dominate landscapes, they introduce novel elements into environments, including artificial light, noise pollution, and anthropogenic food sources. One understudied form of anthropogenic food is refuse from restaurants, which can alter wildlife populations and, in turn, entire wildlife communities by providing a novel and stable food source. Using data from the Maricopa Association of Governments and the Central Arizona-Phoenix Long Term Ecological Research (CAP LTER) project, we investigated whether and how the distribution of restaurants influences avian communities. The research aimed to identify restaurants, and thus the associated food they may provide, as the driver of potential patterns by controlling for other influences of urbanization, including land cover and the total number of businesses. Using generalized linear mixed models, we tested whether the number of restaurants within 1 km of bird monitoring locations predict avian community richness and abundance and individual species abundance and occurrence patterns. Results indicate that restaurants may decrease avian species diversity and increase overall abundance. Additionally, restaurants may be a significant predictor of the overall abundance of urban-exploiting species, including rock pigeon ( Columba livia ), mourning dove (Zenaida macroura) , and Inca dove ( Columbina Inca ). Understanding how birds utilize anthropogenic food sources can inform possible conservation or wildlife management practices. As this study highlights only correlations, we suggest further experimental work to address the physiological ramifications of consuming anthropogenic foods provided by restaurants and studies to quantify how frequently anthropogenic food sources are used compared to naturally occurring sources.
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- Award ID(s):
- 1832016
- PAR ID:
- 10378748
- Editor(s):
- De Marco Júnior, Paulo
- Date Published:
- Journal Name:
- PLOS ONE
- Volume:
- 17
- Issue:
- 10
- ISSN:
- 1932-6203
- Page Range / eLocation ID:
- e0269334
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1371/journal.pone.0269334
