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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.

Social interaction among animals can occur under many contexts, such as during foraging. Our knowledge of the regions within an avian brain associated with social interaction is limited to the regions activated by a single context or sensory modality. We used 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) to examine American crow (Corvus brachyrhynchos) brain activity in response to conditions associated with communal feeding. Using a paired approach, we exposed crows to either a visual stimulus (the sight of food), an audio stimulus (the sound of conspecifics vocalizing while foraging) or both audio/visual stimuli presented simultaneously and compared to their brain activity in response to a control stimulus (an empty stage). We found two regions, the nucleus taenia of the amygdala (TnA) and a medial portion of the caudal nidopallium, that showed increased activity in response to the multimodal combination of stimuli but not in response to either stimulus when presented unimodally. We also found significantly increased activity in the lateral septum and medially within the nidopallium in response to both the audio-only and the combined audio/visual stimuli. We did not find any differences in activation in response to the visual stimulus by itself. We discuss how these regions may be involved in the processing of multimodal stimuli in the context of social interaction.

Potential impacts to rural livelihoods by large carnivores, such as gray wolves (Canis lupus), increase economic liability and fear among residents, resulting in social conflicts over wildlife issues. Strategies have been developed to promote non-lethal predator management in rural communities, but there is limited understanding of why ranchers choose to participate in such programs. We conducted semi-structured interviews (n = 45) of ranchers in Washington state, United States, asking open-ended questions to explore their perspectives on conflict mitigation. Interviews were analyzed using Grounded Theory. Ranchers mentioned five broad types of mitigation strategies: state agency intervention (i.e., calling the state agency in charge of wolf management to request either compensation or lethal wolf removal), biological measures (e.g., use of guard animals), physical measures (e.g., fences), human interference (cowboys and cowgirls), and indirect measures (e.g., husbandry practices). Motivations for participating in non-lethal mitigation strategies included previous positive interactions with wildlife agency officials, an understanding of the importance of wolves to the ecosystem, and clearly outlined guidelines on how to deal with wolf interactions. Barriers that hindered rancher participation included disdain for regulation both regarding the Endangered Species Act and the state's requirements for accessing damage compensation, which were perceived to be extensive and over-reaching. Negative attitudes toward wolf recovery included fear of wolves and perceived damage that wolves inflict on rural lives and livelihoods. Ranchers' motivations and perceived barriers for participating in mitigation strategies included sociopolitical and economic factors. Thus, we suggest that in addition to mitigating economic loss, wildlife managers address the intangible social costs that deter ranchers' participation in mitigation strategies through continued dialogue.

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).

Many species, including humans, have emerged via complex reticulate processes involving hybridisation. Under certain circumstances, hybridisation can cause distinct lineages to collapse into a single lineage with an admixed mosaic genome. Most known cases of such ‘speciation reversal’ or ‘lineage fusion’ involve recently diverged lineages and anthropogenic perturbation. Here, we show that in western North America, Common Ravens (Corvus corax) have admixed mosaic genomes formed by the fusion of non-sister lineages (‘California’ and ‘Holarctic’) that diverged ~1.5 million years ago. Phylogenomic analyses and concordant patterns of geographic structuring in mtDNA, genome-wide SNPs and nuclear introns demonstrate long-term admixture and random interbreeding between the non-sister lineages. In contrast, our genomic data support reproductive isolation between Common Ravens and Chihuahuan Ravens (C. cryptoleucus) despite extensive geographic overlap and a sister relationship between Chihuahuan Ravens and the California lineage. These data suggest that the Common Raven genome was formed by secondary lineage fusion and most likely represents a case of ancient speciation reversal that occurred without anthropogenic causes., Speciation reversal is known mainly from recently diverged lineages that have come into secondary contact following anthropogenic disturbance. Here, Kearns et al. use genomic and phylogenomic analyses to show that the Common Raven (Corvus corax) was formed by the ancient fusion of two non-sister lineages of ravens.

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.

Urban areas are rapidly expanding and natural habitats are being transformed changing the face of the local biota and the resources available for it. We studied how a purported sensitive species, the Pileated Woodpecker (Dryocopus pileatus), breeds and survives in response to rapid and extensive land cover change as urbanization reduces and potentially isolates forest. From 2009 to 2013, we used radio-telemetry to find woodpecker nests and roost sites, and recorded nest success and adult survivorship at suburban sites in the greater Seattle area, Washington. We found 14 nests and 17 confirmed roost sites. Nests were mostly placed on dead trees or dead branches of trees, primarily on red alder (Alnus rubra) of smaller size than those reported for natural sites. The average productivity of the nests was 2.0 young and most nests (13/14) fledged at least one young. Annual adult survivorship varied across years, but the average (83.0%) was higher than what has been reported for nearby natural sites of the Pacific Northwest. Our results suggest that important components of woodpecker fitness in suburban areas may be as good or better than in natural nearby areas. Therefore, suburban forest mosaics can complement conservation in protected areas. Appreciating the importance of human-dominated lands may result on a more integrated view of the urban-wildland gradient and its role on the conservation of the natural world.

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.

Following the call from the United Nations Convention on Biological Diversity “Cities & Biodiversity Outlook” project to better preserve urban biodiversity, this paper presents stakeholder-specific statements for bird conservation in city environments. Based upon the current urban bird literature we focus upon habitat fragmentation, limited habitat availability, lack of the native vegetation and vegetation structure as the most important challenges facing bird conservation in cities. We follow with an overview of the stakeholders in cities, and identify six main groups having the greatest potential to improve bird survival in cities: i) urban planners, urban designers and (landscape) architects, ii) urban developers and engineers, iii) homeowners and tenants, iv) companies and industries, v) landscaping and gardening firms, vi) education professionals. Given that motivation to act positively for urban birds is linked to stakeholder-specific advice, we present ten statements for bird-friendly cities that are guided by an action perspective and argument for each stakeholder group. We conclude with a discussion on how the use of stakeholder-specific arguments can enhance and rapidly advance urban bird conservation action.

While a growing number of animals demonstrate avoidance of areas associated with conspecific death, the extent to which wild populations may use these experiences to learn about novel predators remains unclear. Here we demonstrate with experiments that wild American crows, Corvus brachyrhynchos, respond to dead conspecifics by mobbing, increasing the time to approach food in areas associated with these events, and learning new predators based on their proximity to dead crows and hawks. Avoidance of either dead conspecifics or areas associated with them is not shared by another urban bird, the rock pigeon, Columba livia. Crows mobbed and increased the time to approach food over the next 72 h after observing novel humans paired with a dead crow, a red-tailed hawk, Buteo jamaicensis, or a hawk with a dead crow. The sight of a dead pigeon did not elicit these responses. These findings suggest that, for crows, dead conspecifics, but not dead heterospecifics, represent a salient danger akin to the observation of a predator. On the day the stimulus was presented, the number of trials that resulted in mobbing and avoidance of the food was strongest when crows were presented a hawk with a dead crow. In addition, we demonstrate that crows use the proximity of a human to predators, to dead conspecifics and to predators with dead conspecifics as cues to learn to recognize and subsequently scold the associated human after only one training event, and that this association can last 6 weeks. Together, our results support previous findings that crows learn places associated with conspecific death, and further demonstrate that crows can learn and remember people who appear complicit in these events.

Correlations between urbanization and biodiversity are well known, but the causes driving such associations are lacking. We used a long-term, quasi-experimental approach to study the responses of avian communities to suburban and exurban development around Seattle, WA, USA. We measured indices of bird abundance, reproduction, and survival for 12 years at many locations, including 5 forest ‘reserves,’ 10 existing ‘developments,’ and 11 ‘changing’ sites where ongoing development converted forests to single-family residential neighborhoods. In the first few years of clearing, building, and occupation of new neighborhoods by humans avian communities shifted from those typical of second-growth forest to those more characteristic of developments. During this time avian diversity increased and numerical dominance by abundant birds declined. Species that adapted and exploited development reproduced more successfully there than did forest-dependent species that avoided development. Adults of species that thrived in developments attained equal annual survival across reserved to developed landscapes, while species that avoided neighborhoods tended to survive poorly outside of reserves. The humans living in our study areas frequently fed birds and provided nest boxes. These actions were positively correlated with increases in secondary cavity nesting and seed eating birds. Humans also maintained outdoor cats and 11 % of humans both fed birds and let their cats outside. These actions were negatively correlated with the abundance of birds regularly using feeders. We suggest that a key management goal in urban ecosystems is the maintenance of avian diversity because a diverse avifauna engages a diversity of humans.

American Crows (Corvus brachyrhynchos) aggressively mob a variety of natural predators and learn to recognize unique threats. Because mobbing is a costly and risky behavior, we hypothesized that crows would selectively ignore benign heterospecifics that look similar to predators, perhaps even learning to do so. Through a series of natural observations and experiments we found that American Crows were more likely to mob Red-tailed Hawks (Buteo jamaciensis) and Bald Eagles (Haliaeetus leucocephalus) than Ospreys (Pandeon haliaetus). Mobbing intensity was higher to a taxidermic mount of a Red-tailed Hawk than to a mount of an Osprey, indicating that mobbing increases with the risk posed by the predator. However, we also found that Ospreys were more likely to be mobbed in locations where they rarely occur, suggesting that crow populations that frequently encounter Ospreys habituate to this benign raptor. The extensive distribution of Ospreys and resulting co-occurrence with many mobbing species sugge...

As urban areas have grown in population, use of nearby natural areas for outdoor recreation has also increased, potentially influencing bird distribution in landscapes managed for conservation. Members of the family Corvidae (crows, ravens, jays, and magpies) have strong interactions with humans and may be directly affected by recreation in wild landscapes. In Mount Rainier National Park, we evaluated the effects of vegetation, visitor use, and the availability of human-subsidized food on the use of landscape features by 4 corvid species: Steller's Jay (Cyanocitta stelleri), Gray Jay (Perisoreus canadensis), Common Raven (Corvus corax), and Clark's Nutcracker (Nucifraga columbiana). We conducted >1,400 point counts across areas that varied in habitat and in the degree of human recreational impact. We calculated predicted occupancy values while allowing for variation in detection probability. In addition to species-specific suites of vegetation and landscape variables, we found that patterns of hu...