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Two datasets with metadata are included. One for analysis of detection the other for analysis of occupancy.

Research on the evolutionary ecology of urban areas reveals how human-induced evolutionary changes affect biodiversity and essential ecosystem services. In a rapidly urbanizing world imposing many selective pressures, a time-sensitive goal is to identify the emergent issues and research priorities that affect the ecology and evolution of species within cities. Here, we report the results of a horizon scan of research questions in urban evolutionary ecology submitted by 100 interdisciplinary scholars. We identified 30 top questions organized into six themes that highlight priorities for future research. These research questions will require methodological advances and interdisciplinary collaborations, with continued revision as the field of urban evolutionary ecology expands with the rapid growth of cities.

Crows and other birds in the family Corvidae regularly share information to learn the identity and whereabouts of dangerous predators, but can they use social learning to solve a novel task for a food reward? Here, we examined the factors affecting the ability of 27 wild‐caught American crows to solve a common string pulling task in a laboratory setting. We split crows into two groups; one group was given the task after repeatedly observing a conspecific model the solution and the other solved in the absence of conspecific models. We recorded the crows’ estimated age, sex, size, body condition, level of nervousness, and brain volume using DICOM images from a CT scan. Although none of these variables were statistically significant, crows without a conspecific model and large brain volumes consistently mastered the task in the minimum number of days, whereas those with conspecific models and smaller brain volumes required varying and sometimes a substantial number of days to master the task. We found indirect evidence that body condition might also be important for motivating crows to solve the task. Crows with conspecific models were no more likely to initially solve the task than those working the puzzle without social information, but those that mastered the task usually copied the method most frequently demonstrated by their knowledgeable neighbors. These findings suggest that brain volume and possibly body condition may be factors in learning new tasks and that crows can use social learning to refine their ability to obtain a novel food source, although they must initially learn to access it themselves.

American crows, Corvus brachyrhynchos, often loudly vocalize when gathered around a food source. Because doing so would attract unwanted attention from predators and competitors, animals that have congregated around food are only expected to vocalize if the benefits (e.g. recruiting or announcing themselves to allies, deterring competitors, warning of danger, begging for a meal, appeasing a dominant) outweigh these costs. Here we demonstrate that wild crows change the quality of their calls depending on the amount of food present. The crows near a large food windfall gave shorter calls compared to their vocalizations in food's absence, and playback of these short calls only prompted a mild aggressive response from listening crows. In contrast, the calls given before the appearance of food were longer, and their playback elicited behaviours from the listening crows associated with aggression and territory defence. These findings suggest that crows avoid giving territorial calls near an exploitable food resource and vocalize for other reasons. Taken together, this study provides insights on how the caller's current context can shift the costs and benefits of vocalizing.

This study aims to provide a comprehensive understanding of the role of urban waterbodies in avian ecology, which is instructive for both biodiversity conservation and urban planning. Based on bird surveys conducted in 41 urban parks in Beijing during the breeding and wintering seasons of 2018–2019, and using standardized regression analyses, we identified the specific effects of waterbody attributes on the full avian community and forest bird guilds. We assessed this at multiple spatial scales, first within the focal parks, and then within buffer zones with radius of 200 m and 1000 m. We found that waterbodies can serve as avian diversity “hotspots” in the urban landscape. More specifically, they support avian diversity in the following ways: (1) Parks with waterbodies maintain a higher number of bird species than parks without waterbodies during the breeding season and attract resident forest birds during the wintering season. (2) When not frozen, waterbodies inside and outside parks contribute equally to resident forest bird species richness, while more individuals were attracted by waterbodies within neighborhoods. (3) In parks without waterbodies, the number of forest bird species significantly increases with the number of waterbody patches within neighborhoods, while the corresponding relationship for parks with waterbodies is insignificant. These findings suggest a preference for habitats nearby waterbodies among forest birds residing highly urbanized areas. This study provides new insights into avian ecology in urban landscapes and scientific support for the idea that creating and maintaining urban waterbodies can conserve biodiversity.

Controversial wildlife conservation and management, such as that involving gray wolves (Canis lupus), can be symbolic of broader social conflicts. We conducted an online survey (N = 420) to determine factors shaping public attitudes toward wolf management among residents of Washington state, United States. We used 12 Likert‐type statements to form a single latent construct that represented attitudes toward wolf management in a multi‐use landscape and fit a simple structural equation model to identify demographic predictor variables. The strongest predictors were that voters self‐identifying as Democrats were more likely to hold positive attitudes toward wolves and management to conserve them than those identifying with other political parties (standardized latent variable coefficient = 0.585) and women were more likely than men to hold negative attitudes (−0.459). Older respondents were also more likely to hold negative attitudes (−0.015) and respondents who tried to stay informed about wolf issues were more likely to hold positive attitudes (0.172). Perceived links between wildlife management issues and political ideology may exacerbate community disagreements, hindering coexistence between rural livelihoods and wolves. We recommend appropriate framing and messengers to account for this linkage and improve communication of policy and promote science‐based decision‐making.

Urban areas continue to expand, with cities now containing more than half of the world's population. As cities grow, natural habitat is transformed, changing the face of the local biota and the resources available for it. Wherever woodpeckers are present, the cavities that they excavate provide an important ecological service that facilitates many other species. We studied how the Pileated Woodpecker (Dryocopus pileatus) uses suburban areas. From 2009 to 2013, we used radio-telemetry to determine the annual home range size and habitat use of 13 individuals in 9 suburbs that varied in their level of urbanization (ranging from 5% to 90% forest remaining). We used concentration of use and resource utilization functions to examine vegetative characteristics used by woodpeckers at relatively large (i.e. 1 km2) and more local (i.e. ⅓ ha) scales. The average home range of suburban Pileated Woodpeckers was significantly smaller than expected based on previous studies. Pileated Woodpeckers concentrated th...

Top predators have cascading effects throughout the food web, but their impacts on scavenger abundance are largely unknown. Gray wolves (Canis lupus) provide carrion to a suite of scavenger species, including the common raven (Corvus corax). Ravens are wide‐ranging and intelligent omnivores that commonly take advantage of anthropogenic food resources. In areas where they overlap with wolves, however, ravens are numerous and ubiquitous scavengers of wolf‐acquired carrion. We aimed to determine whether subsidies provided through wolves are a limiting factor for raven populations in general and how the wolf reintroduction to Yellowstone National Park in 1995–1997 affected raven population abundance and distribution on the Yellowstone's Northern Range specifically. We counted ravens throughout Yellowstone's Northern Range in March from 2009 to 2017 in both human‐use areas and wolf habitat. We then used statistics related to the local wolf population and the winter weather conditions to model raven abundance during our study period and predict raven abundance on the Northern Range both before and after the wolf reintroduction. In relatively severe winters with greater snowpack, raven abundance increased in areas of human use and decreased in wolf habitat. When wolves were able to acquire more carrion, however, ravens increased in wolf habitat and decreased in areas with anthropogenic resources. Raven populations prior to the wolf reintroduction were likely more variable and heavily dependent on ungulate winter‐kill and hunter‐provided carcasses. The wolf recovery in Yellowstone helped stabilize raven populations by providing a regular food supply, regardless of winter severity. This stabilization has important implications for effective land management as wolves recolonize the west and global climate patterns change.

We monitored 25 Golden Eagles in Montana, USA, from 2011 to 2015 over 3,601 days using tail-mounted satellite transmitters. Using the best available direct observation and circumstantial evidence, we surmise that only a single eagle (adult female floater) died during monitoring, resulting in a daily survival estimate of 0.9997 (SE = 0.0003) and an annual survival estimate of 0.905 (SE = 0.0907) for a mixture of adult and younger, resident and migrant, breeder and nonbreeder eagles of both genders living in relatively undisturbed regions of the western United States. Under this scenario, adult daily survival averaged 0.9996 (SE = 0.0004) and adult annual survival averaged 0.858 (SE = 0.132).

Expanding human populations favors a few species while extinguishing and endangering many others (Maxwell et al., 2016; Pimm et al., 2014). Understanding how animals perceive and learn about dangers and rewards can aid conservationists seeking to limit abundant or restore rare species (Schakner and Blumstein, 2016; Greggor et al., 2014; Angeloni et al., 2008; Fernández-Juricic and Schulte, 2016). Cognition research is informing conservation science by suggesting how naïve prey learn novel predators (Griffin et al., 2000; Moseby et al., 2015; Schakner et al., 2016; Blumstein, 2016), the mechanisms underlying variation in tolerance of human disturbance (Bostwick et al., 2014), and when natural aversions and fear learning can be leveraged to humanely control predators (Nielsen et al., 2015; Colman et al., 2014; Norbury et al., 2014; Lance et al., 2010; Cross et al., 2013). Insights into the relationships between cognition and adaptability suggest that behavioral inflexibility often presages species rarity (Amiel et al., 2011; Reif et al., 2011; Sol et al., 2008; Zhang et al., 2014; but see Kellert, 1984). Human compassion and restraint are ultimately required to conserve species. Cognitive science can therefore further inform conservation by revealing the complex inner worlds of the animals we threaten and, in partnership with environmental psychologists, explore how such newfound knowledge affects our empathy for other species and ultimately the public’s actions on behalf of species in need of conservation (Collado et al., 2013; Zhang et al., 2014).

Although polygyny is common and regular among a small proportion of North American songbirds, some socially monogamous passerines may also exhibit occasional polygyny. We present evidence for only the second documented case of polygyny within the Vireonidae and the first documentation for polygyny in the endangered songbird the Black-capped Vireo (Vireo atricapilla). We located two simultaneous nests being tended by the same color-banded male vireo in a territory adjacent to an unpaired male. We suspect that differences in territory quality, rather than male quality, unbalanced sex ratios, or asynchronous settlement, were drivers of polygyny in this example.

Real and perceived economic losses are key factors driving negative attitudes and lack of tolerance toward carnivores. Alleviating economic losses through compensation and market-based strategies is one tool for addressing negative human-carnivore interactions. Despite general support among the public for market-based economic incentives to improve coexistence with predators, products marketed as ‘predator-friendly’ are rare in mainstream markets. We explored stakeholders’ perspectives on certification of predator-friendly beef as a market-based economic incentive to enable ranchers to better coexist with gray wolves (Canis lupus) in Washington state, USA. We conducted semi-structured interviews (N = 104) and explored narratives using grounded theory to understand the perspectives of stakeholders involved in the cattle-wolf relationship, including ranchers, wildlife agency personnel, environmental non-government organization employees, beef industry workers, and politicians. Both economic and social factors motivated and constrained ranchers to participate in a program creating a predator-friendly beef label. Ranchers largely perceived marketing their products as predator-friendly to be more of a public outreach opportunity than a new source of income. Most stakeholders perceived an economic opportunity for predator-friendly beef facilitated by existing pro-environmental markets and existence of a private beef processing plant. Based on these results, we propose a design for effectively implementing a predator-friendly beef market. We recommend focusing on the type and objective of the rancher, ensuring local access to beef processing facilities to process small volumes of custom beef, developing a product brand that is favored by ranchers and beef processors, considering viable product pricing , and developing a regulatory process for a potential predator-friendly beef label on the mainstream market.

Financial tools can present a solution to conservation conflicts. However, their effectiveness may be limited unless they address the underlying drivers of conflict. The restoration of controversial megafauna can be tied to a clash of urban and rural values and rejection by rural landowners of government control over their actions. Here, we consider a latent financial opportunity presented by general public support for large predator restoration to maintain a wolf-livestock coexistence program in Washington state, USA. We measured respondents' (N = 420) willingness-to-pay for gray wolf (Canis lupus) conservation and their preferences for program funding mechanisms, including voluntary contributions, mandatory taxes, and a ‘predator-friendly’ ranching certification scheme. Respondents were supportive of a publicly funded program, which represented around USD246 million in estimated economic value. This benefit is more than 150 times the cost of the current government-run program. There were mixed preferences for funding mechanisms, so we recommend adopting multiple approaches. A new funding source would allow the program to be rancher-led, shifting agency from government to rural communities, as well as providing outreach opportunities for ranchers to the urban public. As such, our proposal addresses two of the major socio-political conflicts underlying the wolf debate in North America while also generating funding to protect the ranching industry.

The study of urban birds has increased exponentially in the last century. A prior review of the scientific literature up to the year 2000 found 100 research articles on urban birds, but in the past decade alone over 1000 have been published. Here I review the studies from 2006-2015 to characterize their approach, location, general findings and recent obsessions, with an eye toward suggesting important future directions. Urban ornithology remains centered in the northern hemisphere, although there is a rapid increase in studies from southern, tropical and biodiverse settings. Studies in the north have changed from documentation of the composition of urban avifaunas to include many studies of the demographic response to aspects of urban environments. Studies of pattern remain most common in Latin America, Asia, Africa, New Zealand and the Middle East. Across the world, ornithologists are revealing the rapid evolution of behavioural and morphological adaptations by birds to the urban environment, much of which is due to phenotypic plasticity. The relationship of humans to nature generally and birds specifically has been increasingly studied as a driver of avifaunal change as well as a factor affecting human ethics. Urban ornithology remains rarely experimental, but it has matured to the point of supporting synthetic reviews and meta-analyses that quantify the loss of avian diversity from city centres, characterize successful urban birds, discuss the role of amount and arrangement of vegetation on bird life, and explore the complex relationships between the subsidies and hazards of urban life and the survival and reproduction of birds. Yet much remains to be learned, including how some species thrive in cities with abundant predators; how city form and location affect the peak in avian richness that occurs typically at intermediate levels of urbanisation; the significance of functional biotic homogenization; and the ways in which engaging citizens in urban bird life informs their broader environmental land ethic. This article is protected by copyright. All rights reserved.

A thorough understanding of the effects of spatially and temporally variable demographic drivers of population processes is necessary to accurately evaluate potential source-sink dynamics, estimate long-term population viability, and devise effective management practices. The black-capped vireo (Vireo atricapilla) is an endangered songbird that suffers from high rates of parasitism by the brown-headed cowbird (Molothrus ater). The largest breeding population of vireos is located on the Fort Hood Military Installation in central Texas. This large reserve is well studied but its role in vireo metapopulation dynamics is largely unknown. Furthermore, the evolving cowbird control regime across Fort Hood and nearby isolated populations could impact the local source-sink dynamics. From 2011 through 2014, we monitored breeding vireos at eleven sites across central Texas that varied in cowbird control level. From observations of fecundity and survival, we calculated stochastic and deterministic population growth rates and assessed populations as sources or sinks. We also calculated quasi-extinction probabilities and the sensitivity and elasticity of population growth to demographic parameters. Sites with at least some cowbird control had greater nest success than sites with no cowbird control. We identified four source populations, three of which were on the large Fort Hood reserve and had comprehensive cowbird control across all study years. Although not all sites with cowbird control were sources on average, population dynamics were variable between years and the implementation of cowbird management was generally associated with the growth of local populations. Importantly, source and sink populations were not static, revealing a complex and temporally dynamic system driven largely by variations in adult survival and evolving cowbird control regimes.

Urbanization brings dramatic and sudden changes to ecological conditions affecting natural communities. Cavity-nesting birds, both primary and secondary (hereafter PCN and SCN, respectively), may be limited in this novel environment because of reduced abundance of nesting sites (e.g. snags and cavities) and competition for cavities with non-native species. But humans can also directly and indirectly provide nest sites (e.g., nest boxes, crevices on houses), especially for SCN species, potentially partially compensating for negative effects. We investigated whether and how PCNs and humans facilitated the cavity-nesting bird community along a gradient of urbanization. To do so, we estimated the abundance of cavity-nesting species between 1998 and 2010 at 135, 1-km2 sites that differed in the degree of urbanization (0–100 % forest cover). Also, we found 367 nests on a subset of 31 sites. PCNs (n = 67 nests) nested mostly on snags (98.5 %), while native SCNs (n = 141) used both natural (71.63 %) and anthropogenic (28.37 %) cavities. Non-native SCNs (n = 159 nests) used mostly anthropogenic cavities (98.11 %). PCN abundance facilitated native SCN abundance on sites with more than 12 % forest cover at 1-km2 scale, but not at less forested sites. There, native SCNs nested primarily (59 %) in anthropogenic cavities. Human facilitation allowed native SCNs to successfully use and reproduce where snags were scarce, changing the composition and structure of the cavity-nesting bird community within the most urbanized sites. Flexible nest site selection and human facilitation provide new opportunities for native cavity-nesting birds in a rapidly changing world.

Vancomycin-resistant enterococci [VRE] have been isolated from municipal, hospital and agricultural wastewater, recreational beaches, wild animals, birds and food animals around the world. In this study, American crows (Corvus brachyrhynchos) from sewage treatment plants (WWTP), dairy farms, and a large roost in a restored wetland with corresponding environmental samples were cultured for VRE. A total of 245 samples [156 crows, 89 environmental] were collected and screened for acquired vanA, vanB and/or intrinsic vanC1 genes. Samples were enriched overnight in BHI supplemented with 20μg/mL aztreonam, 4μg/mL vancomycin and plated on m-Enterococcus agar media supplemented with 6μg/mL vancomycin. Selected colonies were grown on BHI media supplemented with 18μg/mL vancomycin. Of these, 24.5% of the crow and 55% the environmental/cow samples were VRE positive as defined by Enterococcus spp. able to grow on media supplemented with 18μg/mL vancomycin. A total of 122 VRE isolates, 43 crow and 79 environmental isolates were screened, identified to species level using 16S sequencing and further characterized. Four vanA E. faecium and multiple vanC1 E. gallinarum were identified from crows isolated from three sites. E. faecium vanA and E. gallinarum vanC1 along with other Enterococcus spp. carrying vanA, vanB, vanC1 were isolated from three environments. All enterococci were multidrug resistant. Crows were more likely to carry vanA E. faecium than either the cow feces or wetland waters/soils. Comparing E. gallinarum vanC1 from crows and their environment would be useful in determining whether crows share VRE strains with their environment.

Animals utilize a variety of auditory and visual cues to navigate the landscape of fear. For some species, including corvids, dead conspecifics appear to act as one such visual cue of danger, and prompt alarm calling by attending conspecifics. Which brain regions mediate responses to dead conspecifics, and how this compares to other threats, has so far only been speculative. Using 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) we contrast the metabolic response to visual and auditory cues associated with a dead conspecific among five a priori selected regions in the American crow (Corvus brachyrhynchos) brain: the hippocampus, nidopallium caudolaterale, striatum, amygdala, and the septum. Using a repeated-measures, fully balanced approach, we exposed crows to four stimuli: a dead conspecific, a dead song sparrow (Melospiza melodia), conspecific alarm calls given in response to a dead crow, and conspecific food begging calls. We find that in response to observations of a dead crow, crows show significant activity in areas associated with higher-order decision-making (NCL), but not in areas associated with social behaviors or fear learning. We do not find strong differences in activation between hearing alarm calls and food begging calls; both activate the NCL. Lastly, repeated exposures to negative stimuli had a marginal effect on later increasing the subjects’ brain activity in response to control stimuli, suggesting that crows might quickly learn from negative experiences.

Fitness can be profoundly influenced by the age at first reproduction (AFR), but to date the AFR–fitness relationship only has been investigated intraspecifically. Here, we investigated the relationship between AFR and average lifetime reproductive success (LRS) across 34 bird species. We assessed differences in the deviation of the Optimal AFR (i.e., the species-specific AFR associated with the highest LRS) from the age at sexual maturity, considering potential effects of life history as well as social and ecological factors. Most individuals adopted the species-specific Optimal AFR and both the mean and Optimal AFR of species correlated positively with life span. Interspecific deviations of the Optimal AFR were associated with indices reflecting a change in LRS or survival as a function of AFR: a delayed AFR was beneficial in species where early AFR was associated with a decrease in subsequent survival or reproductive output. Overall, our results suggest that a delayed onset of reproduction beyond maturity is an optimal strategy explained by a long life span and costs of early reproduction. By providing the first empirical confirmations of key predictions of life-history theory across species, this study contributes to a better understanding of life-history evolution.