The more things change: species losses detected in Phoenix despite stability in bird–socioeconomic relationships

Abstract

The science of urban ecology has increasingly grappled with the long‐term ramifications of a globally urbanized planet and the impacts on biodiversity. Some researchers have suggested that places with high species diversity in cities simply reflect an extinction debt of populations that are doomed to extinction but have not yet disappeared. The longitudinal studies conducted to date have found species composition shifting with urbanization but have not always documented continued species extirpations post‐urbanization. We used long‐term monitoring data on birds from the greater metropolitan area of Phoenix, Arizona, to measure changes in residential bird communities, species–habitat relationships, and human perceptions of bird species diversity over a five‐year period. Bird richness, occupancy, and abundance decreased, as did the percentage of respondents satisfied with bird variety in their neighborhoods. As in previous analyses for this region, we found that desert specialist species were associated with neighborhoods with xeric landscaping consisting of gravel groundcover, and drought‐tolerant, desert‐adapted vegetation. These species were also found in neighborhoods with high per capita income rates and lower percentages of renters and Hispanic/Latinx residents. Non‐native species were positively associated with neighborhoods containing mesic yards with grass and other water‐intensive vegetation. The proportions of yards in our surveyed neighborhoods with these distinct landscaping types likewise remained relatively stable over five‐year period. Although habitat–species relationships remained unchanged, we detected significant loss of species across the sampling period. Declines were not confined to desert specialist species but included generalist and invader species as well. The parallel reduction in residents’ satisfaction suggests that people perceive some aspect of this environmental degradation. Further investigation into the mechanisms underlying these species losses may reveal options for retaining some desert specialist species, and the uniqueness they contribute to urban fauna.

Predicting the assembly of novel communities in urban ecosystems

“…The y-axis represents the dissimilarity in the species composition between patches (bdiversity). Modified from Leibold and Chase (2017c) a combination of social and environmental factors (Lerman and Warren 2011;Lerman et al 2012bLerman et al , 2018Cook et al 2012;Belaire et al 2014;Warren et al 2019), with the extent of available habitat often being the delimiting factor that determines urban biodiversity (Beninde et al 2015).…”

Long‐term effects of land‐use change on bird communities depend on spatial scale and land‐use type

“…Declines in bird communities in the southwestern United States have been reported in the desert in response to climate change (Iknayan and Beissinger 2018) and in riparian areas in response to recent large-scale biocontrol efforts to defoliate nonnative riparian vegetation (Darrah and van Riper 2018) and to urbanization (Banville et al 2017). And although previous work has investigated bird communities in urban areas in this region (Lerman and Warren 2011, Lerman et al 2012, Warren et al 2019, studies comparing long-term bird community dynamics in natural vs. anthropogenically modified habitats together are lacking.…”

“…Riparian areas in the desert southwest are a critical habitat for bird conservation due to their importance as a migratory pathway (Skagen et al 2005). And although previous work has investigated bird communities in urban areas in this region (Lerman and Warren 2011, Lerman et al 2012, Warren et al 2019, studies comparing long-term bird community dynamics in natural vs. anthropogenically modified habitats together are lacking. And although previous work has investigated bird communities in urban areas in this region (Lerman and Warren 2011, Lerman et al 2012, Warren et al 2019, studies comparing long-term bird community dynamics in natural vs. anthropogenically modified habitats together are lacking.…”

Thermal flexibility and a generalist life history promote urban affinity in butterflies

“…While the evidence is clear that urbanization can significantly alter biological communities (Fenoglio et al, 2020), in many cases leading to biotic homogenization (McKinney, 2006), there is a large range of responses among species (Gippet et al, 2017; Lintott et al, 2016; Threlfall et al, 2012). Some species have adapted to (Homola et al, 2019), and are even thriving in, urban environments (Evans & Gawlik, 2020), while others have been extirpated by urbanization processes (Warren et al, 2019). In general, species can be placed along a continuum according to their response to urban environments.…”