Urban-adapted Species Research Articles

Scavengers in the human-dominated landscape: an experimental study.

Rapid urbanization is a major cause of habitat and biodiversity loss and human-animal conflict. While urbanization is inevitable, we need to develop a good understanding of the urban ecosystem and the urban-adapted species, in order to ensure sustainable cities for our future. Scavengers play a major role in urban ecosystems, and often, urban adaptation involves a shift towards scavenging behaviour in wild animals. We experimented at different sites in the state of West Bengal, India, to identify the scavenging guild within urban habitats, in response to human-provided food. Our study found a total of 17 different vertebrate species across 15 sites, over 498 sessions of observations. We carried out network analysis to understand the dynamics of the system and found that the free-ranging dog and common myna were key species within the scavenging networks. This study revealed the complexity of scavenging networks within human-dominated habitats. This article is part of the theme issue 'Connected interactions: enriching food web research by spatial and social interactions'.

Urbanisation-associated shifts in the avian metabolome within the annual cycle

While organisms have evolved to cope with predictable changes in the environment, the rapid rate of current global change presents numerous novel and unpredictable stressors to which organisms have had less time to adapt. To persist in the urban environment, organisms must modify their physiology, morphology and behaviour accordingly. Metabolomics offers great potential for characterising organismal responses to natural and anthropogenic stressors at the systems level and can be applied to any species, even without genomic knowledge. Using metabolomic profiling of blood, we investigated how two closely related species of passerine bird respond to the urban environment. Great tits Parus major and blue tits Cyanistes caeruleus residing in urban and forest habitats were sampled during the breeding (spring) and non-breeding (winter) seasons across replicated sites in southern Sweden. During breeding, differences in the plasma metabolome between urban and forest birds were characterised by higher levels of amino acids in urban-dwelling tits and higher levels of fatty acyls in forest-dwelling tits. The suggested higher rates of fatty acid oxidation in forest tits could be driven by habitat-associated differences in diet and could explain the higher reproductive investment and success of forest tits. High levels of amino acids in breeding urban tits could reflect the lack of lipid-rich caterpillars in the urban environment and a dietary switch to protein-rich spiders, which could be of benefit for tackling inflammation and oxidative stress associated with pollution. In winter, metabolomic profiles indicated lower overall levels of amino acids and fatty acyls in urban tits, which could reflect relaxed energetic demands in the urban environment. Our metabolomic profiling of two urban-adapted species suggests that their metabolism is modified by urban living, though whether these changes represent adaptative or non-adaptive mechanisms to cope with anthropogenic challenges remains to be determined.

Exploring the potential effects of forest urbanization on the interplay between small mammal communities and their gut microbiota

Urbanization significantly impacts wild populations, favoring urban dweller species over those that are unable to adapt to rapid changes. These differential adaptative abilities could be mediated by the microbiome, which may modulate the host phenotype rapidly through a high degree of flexibility. Conversely, under anthropic perturbations, the microbiota of some species could be disrupted, resulting in dysbiosis and negative impacts on host fitness. The links between the impact of urbanization on host communities and their gut microbiota (GM) have only been scarcely explored. In this study, we tested the hypothesis that the bacterial composition of the GM could play a role in host adaptation to urban environments. We described the GM of several species of small terrestrial mammals sampled in forested areas along a gradient of urbanization, using a 16S metabarcoding approach. We tested whether urbanization led to changes in small mammal communities and in their GM, considering the presence and abundance of bacterial taxa and their putative functions. This enabled to decipher the processes underlying these changes. We found potential impacts of urbanization on small mammal communities and their GM. The urban dweller species had a lower bacterial taxonomic diversity but a higher functional diversity and a different composition compared to urban adapter species. Their GM assembly was mostly governed by stochastic effects, potentially indicating dysbiosis. Selection processes and an overabundance of functions were detected that could be associated with adaptation to urban environments despite dysbiosis. In urban adapter species, the GM functional diversity and composition remained relatively stable along the urbanization gradient. This observation can be explained by functional redundancy, where certain taxa express the same function. This could favor the adaptation of urban adapter species in various environments, including urban settings. We can therefore assume that there are feedbacks between the gut microbiota and host species within communities, enabling rapid adaptation.

Seasonal Dynamics of Butterfly Communities in Different Habitats of Ranchi, Jharkhand

This research investigates the seasonal dynamics of butterfly communities across various habitats in the Ranchi district of Jharkhand. Butterflies, being sensitive indicators of environmental changes, offer valuable insights into the health and biodiversity of ecosystems. The study aimed to understand the habitat preferences, seasonal distribution patterns, and factors influencing butterfly diversity in different landscapes within the Ranchi region. Butterflies play a crucial role in ecosystems as pollinators and are considered bioindicators of environmental health. The diversity and distribution of butterflies are influenced by various factors, including habitat type, climate, and vegetation. Ranchi, located in the state of Jharkhand, offers a diverse range of habitats, from urban green spaces to forested areas and wetlands. This research seeks to contribute to the understanding of how these diverse habitats influence the seasonal dynamics of butterfly communities. The primary objective of this study was to assess the seasonal variations in butterfly communities across different habitats in Ranchi. Specific goals included identifying key habitat preferences of butterflies, documenting seasonal changes in species composition, and exploring potential factors influencing butterfly diversity. By achieving these objectives, the research aimed to provide valuable information for conservation and management efforts in the region. Field surveys were conducted over a period of 12 months, covering distinct seasons in Ranchi. Sampling sites were selected to represent various habitats, including urban parks, forested areas, wetlands, and rural landscapes. Standard butterfly survey techniques, such as transect walks and netting, were employed to collect data on species composition and abundance. Additionally, environmental variables, including temperature, humidity, and vegetation cover, were recorded to analyze their potential impact on butterfly communities. The study revealed significant seasonal variations in butterfly diversity across different habitats. Urban green spaces exhibited higher butterfly abundance during the warmer months, with a dominance of common urban-adapted species. In contrast, forested areas showcased a diverse community throughout the year, with distinct species assemblages in each season. Wetland habitats exhibited specific butterfly preferences during the monsoon season, highlighting the importance of these ecosystems for certain species. Environmental variables played a crucial role in shaping butterfly communities. Temperature and vegetation cover were identified as key factors influencing species richness, while humidity levels correlated with the presence of specific moisture-dependent species. The observed results suggest that habitat heterogeneity and microclimatic conditions contribute to the varied patterns of butterfly diversity in Ranchi. This research provides valuable insights into the seasonal dynamics of butterfly communities in Ranchi's diverse habitats. The findings contribute to the development of effective conservation strategies by identifying key areas for preservation and restoration. Moreover, understanding the factors influencing butterfly diversity enhances our ability to predict and mitigate the impacts of environmental changes on these important pollinators. The outcomes of this study emphasize the importance of maintaining diverse habitats for sustaining butterfly populations and, by extension, the overall health of ecosystems in the Ranchi region.

Diversity and Abundance of Breeding Birds, Habitat, and Nesting Substrate Selection in Urban Areas: A Relevant Case from the Southern Slope of the Mediterranean

Urban areas may affect the richness of avian species. The abundance and diversity of urban landscapes offer breeding habitats and nesting resources for urban-adapted species. In our study, we investigated the breeding birds in urban landscapes of Fez’s historical city (Morocco). We used line-transects to search for nests of breeding species, populations, and habitats counting breeding sites and predicting factors (foraging, nesting resources, and urbanization). Furthermore, four habitats counting green gardens, old city walls, urban farms, and urban forests were prospected to search for nests of breeding birds. Among 13 breeding species including 12 resident-breeders, and one breeding migrant, a total of 109 nests were documented. Five species counting Turdus merula, Sylvia atricapilla, Spilopelia senegalensis, Columba livia, and Coloeus monedula were encountered in green gardens; four species counting Athene noctua, Sturnus unicolor, Passer domesticus, and Tachymarptis melba were observed in old city walls. Falco tinnunculus, Fringilla coelebs, and Accipiter nisus occurred in urban forests; and Streptopelia decaocto in urban farms. The recorded nests were divided between cavities (50 nests) and trees (59 nests). In green spaces, nests were distributed among Olea europaea (17), Citrus aurantium (15), Bambusa vulgaris (11), and Eucalyptus globulus (7). In contrast, Olea oleaster and Cupressus sp. hosted only tree nests each, while Populus sp. and Washingtonia filifera hosted only one nest each. Most nests were recorded in habitats rich in nesting trees and close to water sources. On the contrary, the number of nests decreased as the surface and distance of the habitat to the urban center increased. Our data revealed the diversity, habitat use, and nesting substrates of urban breeding bird communities in Morocco and the Southern slope of the Western Palearctic. Future urban plans must integrate measures to provide suitable breeding resources such as cavities of old walls and a high diversity of urban green spaces for birds to enhance their breeding performances, thus promoting the well-being of the population via increasing biodiversity.

Urban habitats and noise impact avian communities and shape vocal mimicry in a songbird

Urban landscapes present problems for wildlife including highly modified habitat, anthropogenic noise pollution, and competition for suitable habitat. These novel selection pressures filter species present in urban habitats or result in changes to behavior. Recent studies show that some bird species sing differently in noisier, urban areas compared to rural areas, and that anthropogenic noise alone can exclude species. We investigated how the level of urbanization affects (1) bird species composition detected acoustically, and (2) the assemblage of species that a songbird mimics from the local bird community. We studied gray catbirds, Dumetella carolinensis, across an urban gradient (Washington, DC to Virginia) and predicted catbirds in urban habitats would mimic fewer species or mimic more urban-adapted species. The results showed avian community composition differed along the urban gradient and was best predicted by impervious surface and noise level. The species composition of catbird mimicry was predicted by site soundscape, indicating catbird mimicry reflects the local avian community. Since urbanization level was found to significantly predict avian community composition, these findings support the hypothesis that urbanization impacts catbird song by influencing the community of sounds available for catbirds to mimic. Catbirds living in habitats of varying levels of urbanization have significantly different songs from catbirds in other habitats, due to their surrounding bird communities and noise levels differing.

Sex ratios and the city: Secondary offspring sex ratios, parental corticosterone, and parental body condition in an urban-adapted bird

The Trivers–Willard hypothesis states that mothers should adjust their offspring sex ratio according to their own condition and the environment they face during breeding. Past tests of this hypothesis have focused on how natural variation in weather, food availability, or predation pressure shapes sex allocation trade-offs. However, anthropogenic activities, such as urbanization, can alter all of the above characteristics presenting animals with novel challenges in optimizing their brood sex ratio. Previous research has examined how urban living influences individual body condition in several bird taxa, but few have explored subsequent impacts on secondary offspring sex ratio. One likely mediator of the link between environmental conditions, parental condition, and sex ratios is corticosterone (CORT), the primary glucocorticoid in birds. Research on CORT’s influence on sex ratios has focused solely on maternal CORT. However, for species with biparental care, paternal CORT or the similarity of maternal and paternal phenotypes may also help ensure that offspring demand matches parental care quality. To test these hypotheses, we explore offspring secondary sex ratios in European starlings (Sturnus vulgaris). We did not find an effect of site or parental body condition on the production of the more costly sex (males). Instead, we found preliminary evidence suggesting that the similarity of maternal and paternal CORT levels within a breeding pair may increase the likelihood of successfully fledging sons. Maternal and paternal CORT were not significant predictors of secondary sex ratio, suggesting that parental similarity, rather than parental CORT alone, could play a role in shaping secondary offspring sex ratios, but additional work is needed to support this pattern. Starlings are considered an urban-adapted species, making them a compelling model for future studies of the relationship between urbanization, parental body condition, and sex ratios.

The development of behavioral and endocrine coping styles in nestlings from urban and rural sites

Urbanization is increasing globally and altering the stressors that animals face in their everyday lives. Organisms often differ in their coping styles—both behavioral and endocrine—across urban to rural habitats. For example, urban animals are often bolder, more exploratory, and mount stronger glucocorticoid stress responses compared to their rural counterparts. While these coping styles are important in shaping fitness across the urban-to-rural gradient, it remains unclear when these differences arise in the life of organisms. We explore the development of coping styles in European starling nestlings (Sturnus vulgaris), an urban-adapted species. We test whether breathing rate, handling struggle rate, and bag struggle rate differ across sites and find no difference in the behavioral coping styles of nestlings raised in urban versus rural sites. We also explore differences in baseline and stress-induced glucocorticoids, finding that urban nestlings develop a stronger stress response than rural birds before fledging the nest. We find no significant correlations between behavioral and endocrine traits for urban or rural birds, which supports the two-tiered model of coping styles. One possibility is that behavioral and endocrine differences develop at different times over the lives of organisms. Our findings support prior work suggesting that behavioral and endocrine coping mechanisms act independently of one another, and suggests that endocrine coping mechanisms develop in early life and before differences in behavioral coping styles might arise. Future work on the mechanisms leading to early-life differences in coping styles—from genetics to maternal effects to environmental effects—is needed to best predict how urban-adapted organisms cope with environmental change. Studies across a greater number of sites will help disentangle site from urbanization effects.

Urban-adapted mammal species have more known pathogens.

The world is rapidly urbanizing, inviting mounting concern that urban environments will experience increased zoonotic disease risk. Urban animals could have more frequent contact with humans, therefore transmitting more zoonotic parasites; however, this relationship is complicated by sampling bias and phenotypic confounders. Here we test whether urban mammal species host more zoonotic parasites, investigating the underlying drivers alongside a suite of phenotypic, taxonomic and geographic predictors. We found that urban-adapted mammals have more documented parasites and more zoonotic parasites: despite comprising only 6% of investigated species, urban mammals provided 39% of known host-parasite combinations. However, contrary to predictions, much of the observed effect was attributable to parasite discovery and research effort rather than to urban adaptation status, and urban-adapted species in fact hosted fewer zoonotic parasites than expected on the basis of their total parasite richness. We conclude that extended historical contact with humans has had a limited impact on zoonotic parasite richness in urban-adapted mammals; instead, their greater observed zoonotic richness probably reflects sampling bias arising from proximity to humans, supporting a near-universal conflation between zoonotic risk, research effort and synanthropy. These findings underscore the need to resolve the mechanisms linking anthropogenic change, sampling bias and observed wildlife disease dynamics.

Winter denning behaviour of striped skunks and interspecific den activity at their dens: implications for pathogen transmission

Context Striped skunks (Mephitis mephitis) occur across a wide range of habitats in North America and co-occur with many wildlife that use similar denning structures. Few studies have quantified interspecific activity at striped skunk dens despite the concomitant implications for pathogen transmission due to direct and indirect contact at shared dens. Further, no studies have examined differences in striped skunk denning behaviour across an urban–rural gradient with various forms and degrees of human modification. Aims Our study described striped skunk denning behaviour in the lower Midwestern United States and assessed interspecific activity at dens. Methods We used radiotelemetry and camera traps to observe winter denning behaviour of radiocollared striped skunks and other sympatric species across an urban–rural gradient in southern Illinois, USA, during November–February 2018–2021. We examined correlations between striped skunks and other species captured in photos at dens. We tested for an effect of human modification on the number of dens used by striped skunks, and the effects of weather and landscape variables on striped skunk denning duration. Key results Striped skunks used 3–21 unique dens during a single winter and denned consecutively in one location for 2–59 days. All individuals were observed denning for ≥8 consecutive days. Three striped skunks participated in communal denning, and ≤3 striped skunks were observed at a den concurrently. Eleven mammalian species were observed at striped skunk dens, and other species were present in 35.3% of photos. Striped skunk presence at a den was positively associated with Virginia opossum (Didelphis virginiana) presence. Human modification had no significant effect on the number of dens used by a striped skunk. Human modification, distance to stream/shoreline, and mean daily temperature had significant negative effects on striped skunk denning duration. Conclusions We demonstrated that winter denning behaviour of striped skunks in southern Illinois, USA, fits into a latitudinal gradient of behaviour across North America, and dens are a shared resource where direct and indirect intraspecific and interspecific interactions occur. Implications Weather and landscape features influenced winter denning behaviour of striped skunks and ultimately pathogen transmission potential at dens, trends that could potentially be seen in other urban-adapted species.

Wild boar in the city: Phenotypic responses to urbanisation

Urbanisation is a global human-induced environmental change and one of the most important threats to biodiversity. To survive in human-modified environments, wildlife must adjust to the challenging selection pressures of urban areas through behaviour, morphology, physiology and/or genetic changes. Here we explore the effect of urbanisation in a large, highly adaptable and generalist urban adapter species, the wild boar (Sus scrofa, Linnaeus 1758). From 2005 to 2018, we gathered wild boar data and samples from three areas in NE Spain: one urban (Barcelona municipality, n = 445), and two non-urban (Serra de Collserola Natural Park, n = 183, and Sant Llorenç del Munt i Serra de l'Obac Natural Park, n = 54). We investigated whether urbanisation influenced wild boar body size, body mass, body condition, and the concentration of serum metabolites, considering also the effect of age, sex and use of anthropogenic food resources. Wild boars from the urban area had larger body size, higher body mass, better body condition, and a higher triglyceride and lower creatinine serum concentrations than non-urban wild boars. In addition, urban wild boars consumed food from anthropogenic origin more frequently, which suggests that differences in their diet probably induced the biometric and the metabolic changes observed. These responses are probably adaptive and suggest that wild boars are thriving in the urban environment. Our results show that urbanisation can change the morphological and physiological traits of a large mammal urban adapter, which may have consequences in the ecology and response to urban selection pressures by the species. The phenotypic plasticity shown by wild boars provides both further and new evidence on the mechanisms that allow urban adapter species of greater size to respond to urbanisation, which is expected to continue growing globally over the coming decades.

Sociability of Indian free-ranging dogs (Canis lupus familiaris) varies with human movement in urban areas.

Cohabiting with humans in the same ecological space requires significant variation in the behavioral repertoire of animals. Behavioral variation can potentially improve the chances of survival of an individual. The influence of humans can be measured by quantifying specific behavioral parameters of the interacting individuals. Sociability or the tendency to be friendly toward others is one of many personality traits in animals that can provide us with insights regarding their relationship with humans. Free-ranging dogs are one of the successful urban-adapted species that interact with humans regularly, which, in turn, influences their behavioral properties. In this study, we tested 600 adult dogs from 60 sites across India, categorized as high, low, and intermediate human flux zones, to understand their degree of sociability toward an unfamiliar human. Initially, a "positive vocalization phase" was carried out. Unresponsive dogs were further tested in a "stimulus phase." The first phase was characterized by positive vocal sounds, while the second one included both food and positive vocalization. In addition, we surveyed a total of 1,200 people from the 60 sites to understand their perception of free-ranging dogs. Dogs in the IF zones were highly sociable compared to the other zones. High human flux zone dogs were reluctant to approach initially but showed an increased approach when food was provided. Low human flux zone dogs were the least sociable, and even the food reward had minimal impact on them. Our study provides the first evidence of behavioral variation in the degree of sociability of free-ranging dogs in urban environments. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

The role of invasion and urbanization gradients in shaping avian community composition

Abstract The extent to which native species utilize urban environments depends on species responses to multiple threatening processes. Here, we aimed to quantify changes in bird communities in response to changing habitat structure, invasive species and aggressive native species. We conducted surveys in two independently invaded regions with similar patterns of urban development. The study regions were New South Wales (NSW) and Queensland (QLD), Australia. We observed 127 species in NSW and 144 species in QLD. Most species (NSW 83 and QLD 84) are urban adapters making use of some or all urban sub-environments. Urban avoiders, species only found in remnant vegetation, were the second largest group (urban avoiders: NSW 23 and QLD 31). We found the lowest richness in the most urban sites (urban exploiters: NSW 10 and QLD 15). Using generalized linear mixed models, we found a non-significant relationship between species richness and the abundance of aggressive species like the common myna and noisy miners, Manorina melanocephala, but a significant positive correlation with the percentage of shrub cover at a site. As there is a gradual loss of species with increasing urbanization, retaining higher complexity in vegetation structure in urban areas will support large numbers of species and could help mitigate the potential impacts of aggressive urban-adapted species and habitat loss.

Urbanization has opposite effects on the territory size of two passerine birds

BackgroundUrban expansion has been identified as one of the leading drivers of biodiversity change or loss. For birds, urbanization is specifically related to survival, breeding success, and territory size. Understanding how different birds adjust territory size in response to urbanization is essential for their conservation in urban environments and to better understand why some species are lost and others persist under this condition. We evaluated the effect of urbanization on the territory size of an urban avoider species, White-eared Ground-Sparrow (Melozone leucotis), and an urban adapter species, House Wren (Troglodytes aedon), at five Costa Rican sites.MethodsWe measured the size of 30 ground-sparrow and 28 wren territories using a total of 296 h of observation. We followed each individual for at least 1 h per day for at least 2 days of two consecutive years, and geo-referenced their locations. Territory size was estimated using the minimum convex polygon method. We measured the urban surfaces (roads, buildings, any other paved area, soccer fields, lawns, and gardens with short grass) within territories.ResultsGround-sparrow territories were larger at the highly urbanized site than at the non-urbanized site. Wren territories were larger at the low urbanized site than at the highly urbanized site. We found a positive relationship between urban surface and territory size for the ground-sparrow, but not for the wren.ConclusionsOur results showed that not all birds adjust territory size in the same way in response to urbanization. We showed that urban avoiders probably need to defend larger territories in urban environments to find all the resources required to survive because urban environments may provide insufficient resources such as food or shelter. Urban adapters on the other hand defend smaller territories in urban environments because even small territories may provide sufficient resources. These results suggest specific behavioral adaptations developed by Neotropical birds inhabiting urban environments.

Species composition, abundance and diet of a squamate assemblage from the Carnaval stream headwaters (Buenos Aires, Argentina)

The present work summarizes 10 years of field observations of an exurban squamate assemblage occupying a 1200 ha patch in the suburbs of La Plata City (Los Portenos, Buenos Aires, Argentina). Crossed by two streams (Martin and Carnaval), the area is characterized by intensive horticulture and floriculture, poultry and pig farming, exhibits a low housing density (1 house/ha), and the roads are largely unpaved. This area is under stress due to continuous expansion of the neighboring city in detriment of rural areas, determining a stressing environmental scenario. Field data were complemented and contextualized with museum records of the squamates present in the area and in neighboring departments of La Plata. The field-based species list of squamates from Los Portenos comprises one amphisbaenian (Amphisbaena darwinii = 26 specimens), five snakes (Paraphimophis rustica = 24, Xenodon dorbignyi = 6, Erythrolamprus poecilogyrus = 3, Erythrolamprus semiaureus = 2, Lygophis anomalus = 1), and one lizard (Salvator merianae = 11). The number of species of squamates in Los Portenos was higher than the expected compared with the species from surrounding areas. Fossorial, nocturnal and generalist species were the most abundant in Los Portenos. These urban adapter species lack dietary constraints and their living habits minimize the encounters with humans, who commonly kill them.

Disturbance, but not the right kind: Exurban development does not create habitat for shrubland birds

Exurban development (i.e., low-density residential housing) comprises at least 25% of the contiguous United States and disturbs the natural landscape, typically impairing habitat for forest interior songbirds and creating habitat for urban-adapted species. However, it is poorly known how exurban development affects shrubland birds, which require disturbance to create habitat (i.e., early successional vegetation). Therefore, our objective was to explore landscape patterns associated with shrubland bird occupancy in a forested region undergoing extensive exurban development. To address this objective, we conducted point counts across a natural–exurban gradient in Macon County, North Carolina, USA, and measured 8 land-cover covariates within 200 m and 1,000 m of survey sites. The covariates were percent canopy cover (CANOPY), contagion (CONTAG), percent of the landscape (PLAND) that was developed (DEV), elevation (ELEV), PLAND forest (FOREST), forest edge density (ED_DF), Simpson's landscape diversity index (SIDI), and PLAND shrub (SHRUB). We modeled occupancy for 12 shrubland species using a hierarchical occupancy model that accounts for falsepositive detections. We fit a global model that incorporated all non-collinear covariates and used stochastic search variable selection to determine which covariates showed a relationship with occupancy. The most frequently selected covariate was CANOPY (8 species), followed by ELEV (5 species), DEV (4 species), SIDI (3 species), and CONTAG (2 species). CANOPY and DEV were negatively associated with occupancy. SIDI and CONTAG are both metrics of landscape heterogeneity; heterogeneity was positively associated with occupancy. Additionally, of the study species, generalists showed the highest occupancy rates, while specialists showed the lowest occupancy rates. We suggest that the associations between occupancy and canopy cover and landscape heterogeneity are logical because natural disturbance, in addition to creating early successional habitat, decreases canopy cover and increases landscape heterogeneity. Furthermore, we suggest that exurban development can drive these patterns, but, given the negative (or neutral) relationship between DEV and shrubland bird occupancy, we hypothesize that exurban development as a form of disturbance does not generate early successional habitat. We conclude that exurban development will benefit only a small subset of urban-adapted shrubland species without creating habitat for most shrubland birds, despite exerting considerable disturbance to forested landscapes.

Bird and mammal use of vernal pools along an urban development gradient

Vernal pools in the northeastern US are of conservation concern primarily because of their role as habitat for specialized pool-breeding amphibians, but their use by birds and mammals may also be of interest, especially from the perspective of the impact of urbanization. We describe camera-trapped wildlife (CTW) at 38 vernal pools along an urban development gradient in greater Bangor, Maine, USA. We detected 20 mammal and 39 bird taxa (29 contacted pool water; 39 detected at >1 site). Land cover type within 1000 m (%), within-pool vegetation (%), and amphibian egg mass numbers explained a substantial portion of the variance (40.8%) in CTW assemblage composition. Submerged vegetation within pools and cover by water and impervious surfaces within 1000 m of pools were key site characteristics defining assemblages. We scored the urban-affiliation of taxa and modeled the relationship between weighted assemblage scores for each site and impervious cover. Impervious cover within 1000 m of pools was positively (p < 0.01) related to site urban-affiliation scores. Use probability for red fox increased and snowshoe hare decreased with impervious cover at 1000 m. These results indicate that within-pool vegetation and land cover types at 1000 m influenced bird and mammal assemblages that used study pools and greater impervious cover at 100 and 1000 m was correlated with a shift in assemblages from being dominated by urban-avoider to urban-adapted species. We encourage land use planners and managers to consider the influence of land use practices within 1000 m of vernal pools on birds and mammals, especially near amphibian breeding pools.

Happy to breed in the city? Urban food resources limit reproductive output in Western Jackdaws.

Urban areas expand worldwide, transforming landscapes and creating new challenging habitats. Some bird species, mainly omnivorous feeding on human waste and cavity nesters, commonly breed in these habitats and are, therefore, regarded as urban‐adapted. Although urban areas may provide new nesting sites and abundant human waste, the low breeding success found in some of these species suggests that the poor protein content in human waste might limit breeding parameters. We investigated whether the breeding success of a cavity nester and omnivorous species commonly breeding in urban areas, the Western Jackdaw (Corvus monedula), depended on the availability of good‐quality non‐urban food. We approached the objective by combining a literature review and experiments in the field. With the literature review, we compared jackdaw populations in different habitats across Europe and found that clutch size and number of fledglings per pair decreased with distance to non‐urban foraging grounds, even after controlling for the effect of colony size, latitude, and climate. In two experiments, we tested whether the breeding success of urban pairs could be increased by supplementing high‐quality food, first only during egg formation and second also until chick fledging. Food supplementation during egg formation led to larger eggs and higher hatching success than in urban control nests, but this did not result in higher chick survival. However, when food supplementation was prolonged until fledging in the second experiment, we observed a significant increase of nestling survival. These findings highlight that research and management actions should not only focus on species displaced by urbanization, but also on “urban‐adapted” species, as they might be suffering from a mismatch between availability of nesting sites in buildings and adequate non‐urban food resources. In these cases, nest sites should be provided in or close to adequate food resources.

玉川上水緑道の鳥類種組成に影響する要因

Ecological network is regarded as a possible way to improve biodiversity in urban landscapes. Though linear vegetated spaces such as greenways and wooded streets are often considered to be important components of urban ecological network, the ecological functions of such linear vegetated spaces have not been clarified well. In the present study, the relationship between avian species composition and vegetation structure were studied in the green road along the Tamagawa Josui Aqueduct during a wintering season and a breeding season. Movements of the observed individuals were also recorded. The results indicated that the avian species composition varied with tree vegetation cover. Landscape scale factors such as woodland area within 500m range and NDVI within 500m range were also influential. Distance from the nearest large woodland was important only in the breeding season while water area within 500m range was important only in winter. Most urban avoider species and some urban adapter species tended to move within the vegetated area along the aqueduct, which indicates that the linear vegetated area could play a role as movement corridor for the species.

Urban Compost Attracts Coyotes, Contains Toxins, and may Promote Disease in Urban-Adapted Wildlife.

Anthropogenic food is often concentrated in cities where it can attract wildlife, promote conflict with people, and potentially spread disease. Although these associations are well-documented for conventional garbage, they are unexplored for many seemingly innocuous and even environmentally friendly attractants such as piles of compost. In this study, we tested the hypothesis that municipal piles of compost are underappreciated and potentially important contributors to a recent rise in encounters with urban-adapted wildlife by attracting wildlife and promoting the spread of wildlife disease. We used remote cameras to compare visitation rates to compost piles and urban natural areas by coyotes (Canis latrans). For each site type, we assessed photographs for evidence of ectoparasites, screened scats for endoparasites, and sampled compost for harmful mycotoxins. At compost piles, visitation rates were eight times more frequent, coyotes with visible parasitic infections were 4.5 times more common, scats were 10 times more likely to contain tapeworm eggs, and mycotoxins were detected in 86% of piles and often at concentrations higher than legal limits for animal feed. Greater securement of compost waste in cities may reduce encounters with animals, susceptibility to and spread of disease, and rates of human-wildlife conflict for coyotes and other urban-adapted species.