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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. 

Mosquitoes and the pathogens they carry are increasingly common in urban areas throughout the globe. With urban landscapes, the need to manage mosquitoes is driven by the health risks and nuisance complaints associated with mosquitoes. Controlling the number of mosquitoes may reduce the overall risk of disease transmission but may not reduce nuisance complaints. This study focuses on Maricopa County in Arizona, USA, to investigate the relationship between mosquito abundance and landscape-level and sociodemographic factors on resident perceptions of mosquitoes. We used boosted regression trees to compare how mosquito abundance, collected from Maricopa Vector Control, and landscape factors and social factors, assessed through the Phoenix Area Social Survey, influence survey respondents’ reporting of mosquitoes as a problem. Results show that the landscape and sociodemographic features play a prominent role in how individuals perceive mosquitoes as a problem; specifically, respondents’ perception of their local landscape as messy and the distance to landscape features such as wetlands have more substantial roles in shaping perceptions. This work can highlight how potential mosquito and non-mosquito-related communications and management efforts may improve residents’ satisfaction with mosquito control or other wildlife management efforts, which can help inform best practices for vector control agencies. 

Despite the social and ecological importance of residential spaces across the country, scant research examines urban yard management policies in the U.S. Governance scholarship points to the implementation challenges of navigating policy language. Our research provides an exploration of yard ordinance language, with implications for communities across the U.S. Specifically, we sought to determine whether—and in what instances—vegetation- and groundcover-related yard ordinances in the U.S. are ambiguous or clear. Our findings suggest that ordinances are often ambiguous when referring to the state or quality of the constituent parts that make up the residential yard (e.g., “neat” or “orderly”). Yet they are clear when providing guidance about what plant species are or are not allowed, or when articulating specific requirements regarding the size or dimensions of impervious surfaces and plants. We discuss the policy implications of these findings, especially in the context of how such policies may invite the subjective judgment by enforcers, leaving open the potential for discriminatory enforcement, especially with regard to marginalized communities where different cultural values and esthetics may be expressed in yards. 

The impacts of urbanization on bird biodiversity depend on human–environment interactions that drive land management. Although a commonly studied group, less attention has been given to public perceptions of birds close to home, which can capture people's direct, everyday experiences with urban biodiversity. Here, we used ecological and social survey data collected in the metropolitan region of Phoenix, Arizona, USA, to determine how species traits are related to people's perceptions of local bird communities. We used a trait‐based approach to classify birds by attributes that may influence human–bird interactions, including color, size, foraging strata, diet, song, and cultural niche space based on popularity and geographic specificity. Our classification scheme using hierarchical clustering identified four trait categories, labeled as Metropolitan (gray, loud, seedeaters foraging low to ground), Familiar (yellow/brown generalist species commonly present in suburban areas), Distinctive (species with distinguishing appearance and song), and Hummingbird (hummingbird species, small and colorful). Strongly held beliefs about positive or negative traits were also more consistent than ambivalent ones. The belief that birds were colorful and unique to the regional desert environment was particularly important in fortifying perceptions. People largely perceived hummingbird species and birds with distinctive traits positively. Similarly, urban‐dwelling birds from the metropolitan trait group were related to negative perceptions, probably due to human–wildlife conflict. Differences arose across sociodemographics (including income, age, education, and Hispanic/Latinx identity), but explained a relatively low amount of variation in perceptions compared with the bird traits present in the neighborhood. Our results highlight how distinctive aesthetics, especially color and song, as well as traits related to foraging and diet drive perceptions. Increasing people's direct experiences with iconic species tied to the region and species with distinguishing attributes has the potential to improve public perceptions and strengthen support for broader conservation initiatives in and beyond urban ecosystems.

 

Predator fear effects influence reproductive outcomes in many species. In non‐urban systems, passerines often respond to predator cues by reducing parental investment, resulting in smaller and lighter nestlings. Since trophic interactions in urban areas are highly altered, it is unclear how passerines respond to fear effects in human‐altered landscapes. Nestlings of passerines in urban areas also tend to be smaller and lighter than their rural counterparts and are often exposed to high densities of potential predators yet experience lower per capita predation—the predation paradox. We suggest fear effects in urban habitats could be a significant mechanism influencing nestling condition in birds, despite lowered predation rates. We manipulated exposure of nesting birds to adult‐consuming predator risk in residential yards across a gradient of urbanization to determine the relative influence of urbanization and fear on nestling condition. We found nestlings had reduced mass in nests exposed to predator playbacks as well as in more urban areas. Despite lower per capita predation rates in urban areas, fear effects from increased predator densities may influence passerine fitness through reduced nestling condition. As urban development expands, biodiversity conservation hinges on a deeper mechanistic understanding of how urbanization affects reproductive outcomes.