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1. Residential yard management and landscape cover affect urban bird community diversity across the continental USA

   https://doi.org/10.1002/eap.2455  

   Lerman, Susannah_B; Narango, Desirée_L; Avolio, Meghan_L; Bratt, Anika_R; Engebretson, Jesse_M; Groffman, Peter_M; Hall, Sharon_J; Heffernan, James_B; Hobbie, Sarah_E; Larson, Kelli_L; et al (October 2021, Ecological Applications)

   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. 

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2. Residential yard management and landscape cover affect urban bird community diversity across the continental USA

   Lerman, Susannah B.; Narango, Desiree. L.; Avolio, Meghan L.; Bratt, Anika R.; Engebretson, Jesse M.; Groffman, Peter M.; Hall, Sharon J.; Hefferenan, James B.; Hobbie, Sarah E.; Larson, Kelli L.; et al (January 2021, Ecological applications)

   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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3. Network dynamics revealed from eDNA highlight seasonal variation in urban mammal communities

   https://doi.org/10.1111/1365-2656.70082  

   Hallam, Jane; Harris, Nyeema_C (June 2025, Journal of Animal Ecology)

   Abstract Urban ecosystems are expanding rapidly, significantly altering natural landscapes and impacting biodiversity.Here we explore seasonal variation in mammal diversity using environmental DNA (eDNA) from soil samples collected during winter and summer across 21 urban parks in Detroit, Michigan. We estimated gamma (regional), alpha (local) and beta (compositional change) diversity to determine if seasonal shifts, reflecting winter scarcity and summer abundance in mammal community composition and human activity, could be detected using eDNA. We expected that larger parks would exhibit greater diversity and higher seasonal turnover, consistent with the species‐area relationship (SAR) and hypothesised that increased summer resource availability would lead to decreased network density as species disperse more broadly.We found that urban parks show subtle, park‐specific changes in community composition influenced by both ecological and anthropogenic factors, with species including striped skunk, brown rat and groundhog responsible for the observed seasonal variation. Consistent with the SAR, larger parks supported higher species richness and diversity. Ecological network analysis, focusing on metrics such as clustering coefficient and network density, revealed a decrease in the overall connectivity and cohesiveness of species interactions from winter to summer, supporting our hypothesis of broader species dispersal during resource‐rich periods. Notably, human DNA was prevalent in all parks, alongside detections of pig and cow eDNA, potentially reflecting human disturbance and anthropogenic food inputs.Our findings underscore the efficacy of eDNA analysis in capturing urban mammal community dynamics, the impact of human activities on biodiversity and its potential as a valuable tool for urban ecological research. Ultimately, enhancing monitoring capacity aids in conservation and urban planning efforts that will promote human‐wildlife coexistence and preserve the socio‐ecological benefits stemming from biodiversity across cityscapes. 

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4. Soil microbiomes in lawns reveal land-use legacy impacts on urban landscapes

   https://doi.org/10.1007/s00442-023-05389-8  

   Thompson, Grant L.; Bray, Natalie; Groffman, Peter M.; Kao-Kniffin, Jenny (June 2023, Oecologia)

   Abstract Land-use change is highly dynamic globally and there is great uncertainty about the effects of land-use legacies on contemporary environmental performance. We used a chronosequence of urban grasslands (lawns) that were converted from agricultural and forested lands from 10 to over 130 years prior to determine if land-use legacy influences components of soil biodiversity and composition over time. We used historical aerial imagery to identify sites in Baltimore County, MD (USA) with agricultural versus forest land-use history. Soil samples were taken from these sites as well as from existing well-studied agricultural and forest sites used as historical references by the National Science Foundation Long-Term Ecological Research Baltimore Ecosystem Study program. We found that the microbiomes in lawns of agricultural origin were similar to those in agricultural reference sites, which suggests that the ecological parameters on lawns and reference agricultural systems are similar in how they influence soil microbial community dynamics. In contrast, lawns that were previously forest showed distinct shifts in soil bacterial composition upon recent conversion but reverted back in composition similar to forest soils as the lawns aged over decades. Soil fungal communities shifted after forested land was converted to lawns, but unlike bacterial communities, did not revert in composition over time. Our results show that components of bacterial biodiversity and composition are resistant to change in previously forested lawns despite urbanization processes. Therefore land-use legacy, depending on the prior use, is an important factor to consider when examining urban ecological homogenization. 

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5. Habitat complexity, connectivity, and introduced fish drive pond community structure along an urban to rural gradient

   https://doi.org/10.1002/eap.2828  

   Trovillion, Daniel C.; Sauer, Erin L.; Shay, Gabrielle; Crone, Erin R.; Preston, Daniel L. (March 2023, Ecological Applications)

   Abstract Urbanization can influence local richness (alpha diversity) and community composition (beta diversity) in numerous ways. For instance, reduced connectivity and land cover change may lead to the loss of native specialist taxa, decreasing alpha diversity. Alternatively, if urbanization facilitates nonnative species introductions and generalist taxa, alpha diversity may remain unchanged or increase, while beta diversity could decline due to the homogenization of community structure. Wetlands and ponds provide critical ecosystem services and support diverse communities, making them important systems in which to understand the consequences of urbanization. To determine how urban development shapes pond community structure, we surveyed 68 ponds around Madison, Wisconsin, USA, which were classified as urban, greenspace, or rural based on surrounding land use. We evaluated how landscape and local pond factors were correlated with the alpha diversity of aquatic plants, macroinvertebrates, and aquatic vertebrates. We also analyzed whether surrounding land use was associated with changes in community composition and the presence of specific taxa. We found a 23% decrease in mean richness (alpha diversity) from rural to urban pond sites and a 15% decrease from rural to greenspace pond sites. Among landscape factors, adjacent developed land, mowed lawn cover, and greater distances to other waterbodies were negatively correlated with observed pond richness. Among pond level factors, habitat complexity was associated with increased richness, while nonnative fishes were associated with decreased richness. Beta diversity was relatively high for all ponds due to turnover in composition between sites. Urban ponds supported more nonnative species, lacked a subset of native species found in rural ponds, and had slightly higher beta diversity than greenspace and rural ponds. Our results suggest that integrating ponds into connected greenspaces, maintaining riparian vegetation, preventing nonnative fish introductions, and promoting habitat complexity may mitigate the negative effects of urbanization on aquatic richness. While ponds are small in size and rarely incorporated into urban conservation planning, the high beta diversity of distinct pond communities emphasizes their importance for supporting urban biodiversity. 

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