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The habitat quality of urban forest patches is determined by the composition and structure of vegetation which in turn affects the quality of trophic resources and shelter provided for wildlife species. In addition, urban development in the landscape surrounding forest patches can affect species' movement between patches, further influencing habitat quality. Understanding how species respond to variation in habitat quality among urban forest patches is especially important for species that contribute to ecosystem services and disservices for urban residents. Here, we assessed habitat quality provided by urban forest patches for white‐footed mice (Peromyscus leucopus) because they are one of the key reservoir species for Lyme disease and they influence disease dilution ecosystem services provided by mammal communities. We examined variation in vegetation composition and structure in forest patches across a gradient of landscape‐scale urban development in and around Philadelphia, PA, USA. In particular, we focused on shifts in vegetation composition and structure associated with invasive understory shrubs given their prevalence in our study system. We then quantified the numerical (index of relative abundance) and morphological responses of white‐footed mice to variation in habitat quality. While we observed no significant effects of environmental variables on our index of mouse relative abundance in forest patches, environmental variables associated with vegetation structure and composition were associated with shifts in mouse morphology. Most notably, mice were larger at sites with more invasive shrub species. This indicates that invasive understory shrubs may be creating higher‐quality habitat for white‐footed mice. Because larger‐bodied mice are likely to feed more ticks, this result has significant implications for Lyme disease dynamics in urban areas, such as amplified transmission. [ABSTRACT FROM AUTHOR]

In the Anthropocene, the ranges of introduced species are expanding, while extinction‐prone species are contracting. Introductions and extinctions are caused by how species respond to human impacts, but it is unknown why the ranges of some species expand and some contract. Here, we test whether this opposite response of human impact is due to introduced and extinction‐prone species falling at opposite ends of geographic, evolutionary, or ecological trait continua. We constructed a database of native range maps, traits, phylogenetic relationships, and the introduction and extinction‐prone status of squamate reptiles with ranges native to the Western Hemisphere. Across > 3000 snake and lizard species (88% of known native squamates), 142 had been introduced elsewhere and 483 were extinction‐prone (i.e. vulnerable, endangered, critically endangered, extinct in the wild, extinct). To explain variation in status, we first tested if the same human‐impacted regions in the Americas contained the native ranges of species of either status. Second, we tested for phylogenetic signal in species status. Finally, we tested the explanatory power of multiple trait continua. The native ranges of introduced and extinction‐prone reptiles were clustered in island regions with high human impact versus mainland regions with lower human impact. Phylogenetic signal was weak for status, but introduced and extinction‐prone species were clustered in different clades. All geographic and ecological traits that explained each status supported the opposite ends hypothesis. Introduced species had larger, edgier ranges, while extinction‐prone species had smaller, simpler ranges. Introduced species were mostly herbivorous/omnivorous, while extinction‐prone species were mostly carnivorous. Introduced species produced larger clutches, while extinction‐prone species had smaller body sizes. In the Anthropocene, the native ranges of introduced and extinction‐prone species are in the same human‐impacted regions where trait continua, having opposite effects, determine whether species ranges expand or contract in the continuing face of global change. [ABSTRACT FROM AUTHOR]

Bolstering the supply of animal‐mediated ecosystem services is an emerging priority in human‐altered landscapes. Such services are driven not only by environmental factors that shape communities of species that provide the service but also by the ecological context that affects the behavior of these species. In this study, we used a field experiment to investigate an ecosystem service that depends on resource use behavior—the removal of littered food waste by birds and squirrels in urban green spaces. We first explore how landscape‐scale urbanization affects the composition of the litter‐removing species community. We then examine two facets of waste removal provisioning—the amount of food removed and the speed of removal—and how they vary across ecological contexts represented by green space type (picnic areas, urban parks, and forest preserves), bird and squirrel abundance, number of people, amount of existing litter, and weather conditions. We found that although landscape‐scale urbanization affected the composition of species within green spaces, service provisioning was context‐dependent. Littered food removal services were provided at higher rates in park and picnic sites than in forest preserves and the abundance of eastern gray squirrels (Sciurus carolinensis) was a main driver of littered food removal services. Where squirrels were abundant, more food was removed, and food removal began and was completed more quickly. When squirrel abundance is accounted for, removal from picnic areas is higher than park sites, indicating context dependence in this service is likely driven by squirrel behavioral responses to ambient food waste levels in these habitats. This study highlights the role of common urban species in providing a valuable ecosystem service and the importance of ecological context in its supply. Efforts to account for animal‐mediated ecosystem services in human‐altered landscapes should address the potential for services to be driven by a single species and context‐dependent factors that influence behavior. [ABSTRACT FROM AUTHOR]

The Caribbean islands are becoming a hotspot for the spread of non-native reptiles. Consistent with this trend, we provide the first documentation of three new lizard species discovered on Aruba, Anolis gingivinus (Cope, 1864), Anolis cristatellus (Duméril and Bibron, 1837), and Hemidactylus frenatus (Duméril and Bibron, 1836). In addition, we provide an updated distribution on Aruba for a previously introduced lizard species, Anolis porcatus (Gray, 1840). All four species were identified phenotypically in the field and identifications were confirmed with genetics. Like most non-native lizards in the Caribbean, they tend to use anthropogenic habitats, and their impacts on Aruba's resident species are not known. [ABSTRACT FROM AUTHOR]

While it is clear that nitrogen (N) deposition impacts the plant diversity of major terrestrial ecosystems, how ground‐dwelling fauna respond to N deposition is less understood.Here, we use a novel experimental methodology of canopy addition of N (CAN) to simulate realistic N deposition and contrast this method to standard understory addition of N (UAN) in a temperate forest and a subtropical forest. We investigated the shifts in community composition and trophic position for ground‐dwelling spiders under different N deposition treatments.We found that the CAN deposition treatment increased the diversity of sit‐and‐wait spiders and the abundance of actively hunting spiders at the subtropical forest, but N treatments had no effect on spider abundance or diversity at the temperate forest. In contrast, UAN treatments had no significant impact on spider communities compared to control treatment. Furthermore, N treatments had significant effects on spider assemblage at subtropical forest. Overall, spiders in the CAN treatment had a higher trophic position as indicated by δ15N isotopic signatures at both forest types.In conclusion, our study suggests that the effects of N deposition on ground‐dwelling spider assemblages depend on N addition approaches. Furthermore, our results suggest that CAN is a more realistic method for understanding the effects of atmospheric N deposition on soil arthropods in forest ecosystems. [ABSTRACT FROM AUTHOR]

The Caribbean islands are becoming a hotspot for the spread of non-native reptiles. Consistent with this trend, we provide the first documentation of three new lizard species discovered on Aruba, Anolis gingivinus (Cope, 1864), Anolis cristatellus (Duméril and Bibron, 1837), and Hemidactylus frenatus (Duméril and Bibron, 1836). In addition, we provide an updated distribution on Aruba for a previously introduced lizard species, Anolis porcatus (Gray, 1840). All four species were identified phenotypically in the field and identifications were confirmed with genetics. Like most non-native lizards in the Caribbean, they tend to use anthropogenic habitats, and their impacts on Aruba's resident species are not known. [ABSTRACT FROM AUTHOR]