A tale of deadly strikes: A nearly century-long literature review of bird-window collisions

Collisions with windows are an important human-related threat to birds in urban landscapes. However, the proximate drivers of collisions are not well understood, and no study has examined spatial variation in mortality in an urban setting. We hypothesized that the number of fatalities at buildings varies with window area and habitat features that influence avian community structure. In 2010 we documented bird-window collisions (BWCs) and characterized avian community structure at 20 buildings in an urban landscape in northwestern Illinois, USA. For each building and season, we conducted 21 daily surveys for carcasses and nine point count surveys to estimate relative abundance, richness, and diversity. Our sampling design was informed by experimentally estimated carcass persistence times and detection probabilities. We used linear and generalized linear mixed models to evaluate how habitat features influenced community structure and how mortality was affected by window area and factors that correlated with community structure. The most-supported model was consistent for all community indices and included effects of season, development, and distance to vegetated lots. BWCs were related positively to window area and negatively to development. We documented mortalities for 16/72 (22%) species (34 total carcasses) recorded at buildings, and BWCs were greater for juveniles than adults. Based on the most-supported model of BWCs, the median number of annual predicted fatalities at study buildings was 3 (range = 0–52). These results suggest that patchily distributed environmental resources and levels of window area in buildings create spatial variation in BWCs within and among urban areas. Current mortality estimates place little emphasis on spatial variation, which precludes a fundamental understanding of the issue. To focus conservation efforts, we illustrate how knowledge of the structural and environmental factors that influence bird-window collisions can be used to predict fatalities in the broader landscape.

Bird-window collisions cause an estimated one billion bird deaths annually in the United States. Building characteristics and surrounding habitat affect collision frequency. Given the importance of collisions as an anthropogenic threat to birds, mitigation is essential. Patterned glass and UV-reflective films have been proven to prevent collisions. At Duke University’s West campus in Durham, North Carolina, we set out to identify the buildings and building characteristics associated with the highest frequencies of collisions in order to propose a mitigation strategy. We surveyed six buildings, stratified by size, and measured architectural characteristics and surrounding area variables. During 21 consecutive days in spring and fall 2014, and spring 2015, we conducted carcass surveys to document collisions. In addition, we also collected ad hoc collision data year-round and recorded the data using the app iNaturalist. Consistent with previous studies, we found a positive relationship between glass area and collisions. Fitzpatrick, the building with the most window area, caused the most collisions. Schwartz and the Perk, the two small buildings with small window areas, had the lowest collision frequencies. Penn, the only building with bird deterrent pattern, caused just two collisions, despite being almost completely made out of glass. Unlike many research projects, our data collection led to mitigation action. A resolution supported by the student government, including news stories in the local media, resulted in the application of a bird deterrent film to the building with the most collisions: Fitzpatrick. We present our collision data and mitigation result to inspire other researchers and organizations to prevent bird-window collisions.

Bird–window collisions (BWCs) are a major threat to avian populations, annually causing up to one billion bird deaths in the US alone and untold numbers of fatalities worldwide. Until recently, there has been limited institutional and governmental recognition of this issue and few coordinated, national‐level efforts to address it. To fill this need, citizen‐science campaigns have stepped in to generate scientific information about BWCs, raise public awareness, and advocate for policy and actions to reduce collisions. We review the BWC issue and showcase how citizen‐science programs in multiple countries have achieved these outcomes. Additional citizen‐driven successes in addressing BWCs are possible if key constraints are overcome, including funding limitations and challenges of proactively engaging stakeholders who can reduce BWCs at scale. Addressing this global conservation issue will also require building upon the recent increase in attention to BWCs by government agencies, nongovernmental organizations, commercial entities, and professional scientists.

Cooler performance breadth in a viviparous skink relative to its oviparous congener

Bird-window collisions are a significant and growing threat to birds, but the issue is still understudied in many geographical areas and stages of the avian annual life cycle. The mountainous topography and numerous distinct biogeoclimatic zones along the Pacific coast of Canada and the United States may result in regional and seasonal differences in collision mortality and species vulnerability to collisions. We surveyed daily for evidence of bird-window collisions over six 21-day periods in fall, early winter, and late winter between 2019 and 2022 at a university campus in southwestern British Columbia, Canada, and assessed individual species’ vulnerability to collisions by examining whether species-specific collision rates were disproportionate to their local abundance. We accounted for poor detectability of some species in fall, by integrating point count data from our study site with mist net capture data from a nearby banding station to improve abundance estimates. Collision mortality peaked in fall, but early winter collision mortality was significantly higher than in the later winter months, potentially due to movements of altitudinal migrants into our low-elevation study area in early winter. We estimated that an average of 885–1,342 (median = 1,095) birds are killed at 51 buildings campus-wide each year between September 15 and February 10, the peak fall migration wintering period. Forest birds, particularly species that switch to highly frugivorous diets in fall and winter, were most vulnerable to collisions across the seasons studied. Non-breeding season mortality due to collisions may be substantial for these species, particularly when considering cumulative mortality across the entire non-breeding period. The potential role of collision mortality in species declines should be further explored by assessing collision frequency and species vulnerability across life cycle stages in other geographical locations, and through improved data on migratory connectivity and linkages between declining breeding populations and non-breeding season mortality.

Simple SummaryCities are complex ecosystems that, while generally contributing to an overall reduction in biodiversity, can support surprisingly unique communities of organisms including bees. Bees are both ecologically and economically essential, therefore preserving and conserving these insects represents a significant challenge as cities continue to expand and diminish surrounding landscapes. Some attempts to support bees in cities have included establishing and improving urban green spaces. Exactly how bees and, to a lesser extent, other pollinators respond to these green spaces in addition to other urban landscape and local features, however, remains incompletely understood. Therefore, this review summarizes the current literature and generalizable trends in pollinator response to urban landscape and local features. While some functional traits or characteristics of bees such as dietary breadth and nesting strategy are more conclusively understood and supported, other characteristics such as sociality remain less generalizable. Lack of knowledge on bee responses to city features is in part due to the individual variation exhibited across different groups and species. To promote greater biodiversity in urban spaces, research should focus on specific responses to urban local and landscape features and how green spaces can be optimized for sustainable bee conservation.Urbanization is a major anthropogenic driver of decline for ecologically and economically important taxa including bees. Despite their generally negative impact on pollinators, cities can display a surprising degree of biodiversity compared to other landscapes. The pollinating communities found within these environments, however, tend to be filtered by interacting local and landscape features that comprise the urban matrix. Landscape and local features exert variable influence on pollinators within and across taxa, which ultimately affects community composition in such a way that contributes to functional trait homogenization and reduced phylogenetic diversity. Although previous results are not easily generalizable, bees and pollinators displaying functional trait characteristics such as polylectic diet, cavity-nesting behavior, and later emergence appear most abundant across different examined cities. To preserve particularly vulnerable species, most notably specialists that have become underrepresented within city communities, green spaces like parks and urban gardens have been examined as potential refuges. Such spaces are scattered across the urban matrix and vary in pollinator resource availability. Therefore, ensuring such spaces are optimized for pollinators is imperative. This review examines how urban features affect pollinators in addition to ways these green spaces can be manipulated to promote greater pollinator abundance and diversity.

Wildlife collisions with human-built structures are a major source of direct anthropogenic mortality. Understanding and mitigating the impact of anthropogenic collisions on wildlife populations require unbiased mortality estimates. However, counts of collision fatalities are underestimated due to several bias sources, including scavenger removal of carcasses between fatality surveys and imperfect detection of carcasses present during surveys. These biases remain particularly understudied for bird-window collisions, the largest source of avian collision mortality. In Stillwater, Oklahoma, USA, we used bird carcasses collected during window collision monitoring to experimentally assess factors influencing scavenging and observer detection, and we employed trail cameras to characterize the scavenger community and timing of scavenging. We recorded nine scavenger species, but the domestic cat and Virginia opossum were responsible for 73% of known-species scavenging events. The most frequent scavenger species were primarily nocturnal, and 68% of scavenging events occurred at night. Scavenger species best predicted time to first scavenging event, season best predicted carcass persistence time, and both season and carcass size predicted whether any carcass remains persisted after scavenging. Our results also suggest that observer detection was influenced by substrate, with greater detection of carcasses on artificial substrates. Our findings related to scavenging timing have important implications for the unbiased estimation of collision mortality because the timing of peak scavenging relative to timing of peak mortality can substantially influence accuracy of adjusted mortality estimates. Further, the differences in correlates for time to first scavenging and time to carcass removal (i.e., persistence time) illustrate the importance of explicitly measuring these often-independent events that are frequently conflated in the anthropogenic mortality literature.

After oviposition, females of the Mediterranean fruit fly Ceratitis capitata Wiedemann deposit a host-marking pheromone on the fruit surface that deters oviposition by conspecifics. Methanolic extracts of fruit fly faeces elicit a similar deterrent effect. The results of laboratory and field experiments using raw methanolic extracts of C. capitata faeces as an oviposition deterrent are reported. Laboratory bioassays revealed a significant positive relationship between concentration of faeces and the inhibition of oviposition responses by C. capitata. Treatment of halves of coffee bushes with methanolic extracts containing 0.1, 1.0 and 10 mg faeces ml(-1) resulted in a significant reduction of infestation only at the highest concentration (P=0.03). Treatment of blocks of coffee bushes with an extract of 10 mg faeces ml(-1) resulted in an 84% reduction in infestation by C. capitata in sprayed plants and a 56% reduction in adjacent untreated coffee bushes surrounding treated plots, probably due to the deterrent effect of host-marking pheromone on fly oviposition. We conclude that faeces contain oviposition deterrent substances that effectively reduce fruit infestations by C. capitata, suggesting a clear potential for the use of this infochemical in integrated management programmes targeted at this pest.

Soaks (areas of mesotrophic/minerotrophic vegetation within acid bog) add to the overall heterogeneity and biodiversity of raised bog landscapes due to the presence of flora and fauna communities not typically associated with acid bog systems. A field experiment was set up to investigate the potential to restore the minerotrophic and aquatic communities that previously occurred within a soak of an oceanic raised bog in Ireland, which has recently undergone acidification with the expansion of acid bog type vegetation. Three different treatments, control (intact sphagnaceous raft), permeable (sphagnaceous raft removed), and enclosed (sphagnaceous raft removed and plots isolated from surrounding surface water influence) were applied to a total of six plots (each measuring 4 × 4 m), each treatment consisting of two replicates. Within 3 years a sphagnaceous raft with similar vegetation to the surroundings had developed in both permeable plots, while aquatic communities similar to those that occurred at the site in the past had established within the enclosed pots. Our results show that with manipulation of local hydrology it is possible to recreate conditions suitable for aquatic plant communities that once characterized the site. The results also give an insight into the likely processes responsible for the initial terrestrialization of the entire soak over the past century. Application of the results in relation to the site and the widespread practice of restoring bog vegetation on degraded peatlands are discussed.

Occurring in China, DPR Korea, Japan, and Russian Federation and classified in the Red List of Chinese Flora as a vulnerable species, Rhodiola sachalinensis Boriss. is used increasingly in cosmetics, dietary supplements, and Traditional Chinese Medicines (TCMs). The aim of this study was to evaluate the (i) conservation status, harvesting and trade levels of R. sachalinensis, (ii) current state of experimental and commercial farming, and (iii) evidence of substitution or interchangeable use of R. sachalinensis with other Rhodiola species. We assessed data from multiple disciplines and languages including studies on R. sachalinensis biology and ecology, information on impacts of wild harvest, management measures, and current levels of cultivation. Our assessment shows that while R. sachalinensis is increasingly produced by cultivation, wild populations are decreasing and face multiple threats. These include (a) habitat loss including due to oil and gas infrastructure development on Sakhalin island, (b) climate change impacts on alpine ecosystems, and (c) overexploitation of wild plants to satisfy the growing commercial demand. Assessments of the conservation status of R. sachalinensis should commence in each Range State, as well as resource assessments and monitoring of harvesting and trade of wild R. sachalinensis. Even with increased reliance on cultivation, biodiversity conservation, and genetic diversity in wild populations are relevant to future use of this species.

Criminology is not just focused on explaining the etiological factors behind crime commission; ultimately the goal is to find and empirically assess policies to control it. A criminology of the State is no different. Over the course of the past two decades, a growing number of scholars of State crime have devoted attention to and research on the issues of controls, yet, there have been relatively few articles that solely focus on the issue of international criminal justice and its ability, or lack thereof, to have a deterrent effect. However, many actors within the field of international criminal justice have heralded the deterrent power of the international criminal justice system and its ability to remove impunity for violations of international criminal law. Likewise, many practitioners and scholars routinely assume a probability at best, to an assumption of sureness, of a powerful deterrent effect for those in high ranking positions, including heads of State, that violate international criminal law. This article examines the potential deterrent effect of international criminal justice, as it pertains to State crime, which is grounded in criminological insights. To do so, we present an overview of the common assumptions of and criminological thinking in deterrence models. This is followed by highlighting those factors most strongly associated with a deterrent effect with State criminality and international criminal justice. The article concludes with a critical examination of the potential of deterrence and how it fails to generate the effects for heads of State and other high ranking officials which so many international public actors, including the international criminal justice system, claims.

Air pollution is the leading environmental risk factor for human health, with millions of deaths annually and significant societal and economic costs. While access to the latest, reliable, and free air quality and health data is vital for informed decision-making, data on air pollution remains limited, especially in low- and middle-income countries (LMICs). The State of Global Air Initiative (SoGA), a collaboration between the Health Effects Institute and the Institute for Health Metrics and Evaluation, addresses this need by presenting comparable data on levels and trends of air quality and the associated health impacts for more than 200 countries and territories and more than 7000 cities around the world. The data are drawn from the Global Burden of Disease (GBD) Study and include data on exposure to air pollutants - fine particulate matter (PM2.5), ozone (O3) and nitrogen dioxide (NO2) and the associated burden of disease – deaths, death rate and disability adjusted life years (DALYs) as well percentage of deaths attributed to specific causes of disease and death. To enhance accessibility and reach, the information is presented in a variety of ways including reports, factsheets, an interactive data app, story maps, and videos, often in multiple languages. All the reports and data resources are accessible via https://www.stateofglobalair.org/. These estimates are produced using a variety of data - air quality estimates are produced from a combination of data from over 10,000 ground-based monitors, satellite observations, and outputs from GEOS-Chem, a chemical transport model. The disease burden estimates are produced using country-specific death and morbidity rates, other health data including disease incidence, population demographics, and exposure-response curves derived from epidemiological studies. However, since the estimates rely on available data on air quality and health, in some cases, estimates are uncertain, particularly in parts of Asia and Africa where data gaps remain. A new dataset featuring estimates for the year 2021 is set to be released shortly. Despite the caveats, such information can be used for public engagement and for making evidence-based decisions to improve air quality and public health. In 2022 alone, the SoGA initiative reached audiences in more than 50 countries, and for many countries, they are the only available estimates for air pollution levels and associated health impacts. The data have been used for public engagement, media reporting and to inform policy decisions, especially in LMICs. These data are also relevant for scientific research. Overall, the SoGA initiative serves to close the gap between scientific research and public understanding on air pollution and its health impacts. In this presentation, we will showcase data from the SoGA platform, review lessons learnt and highlight opportunities for future research and engagement.

The increasingly fast pace of urban conversion of land over the past fifty years in Italy is a phenomenon that has caused serious damage to the national landscape. The problem concerns the whole Italy but is most serious in those areas that produce important savings thanks to the quality of their landscape. In this sense, many references in the European Landscape Convention are recognizable in the Alps that are undoubtedly one of Italy's most iconic landscapes in international perception, along with the cities of art. This paper describes the results of a research on the features of urbanization in the fifties in the Italian Alps, based on uniform historical maps of the entire country. Geostatistical surveys were conducted to determine the distribution changes of urban concentration over time and analyses were developed to point out what landscape and morphological elements have emerged, and are basically confirming greater sensitivity to land artificialization. A number of comparisons based on specific indicators were produced that show the typological and geographic variations of development taking place in the time period studied. Important information has emerged on the different territorial policies implemented by the regions over the long-term.

Projected rates of climate change over the next century are expected to force species to shift ranges, adapt, or acclimate to evade extinction. Predicting which of these scenarios may be most likely is a central challenge for conserving biodiversity in the immediate future. Modeling frameworks that take advantage of intraspecific variation across environmental gradients can be particularly important for meeting this challenge. While these space-for-time approaches are essential for climatic and genomic modeling approaches, mechanistic models that incorporate ecological physiology data into assessing species vulnerabilities rarely include intraspecific variation. A major reason for this gap is the general lack of empirical data on intraspecific geographic variation in avian physiological traits. In this review, we outline the evidence for and processes shaping geographic variation in avian traits. We use the example of evaporative water loss to underscore the lack of research on geographic variation, even in traits central to cooling costs in birds. We next demonstrate how shifting the focus of avian physiological research to intraspecific variation can facilitate greater integration with emerging genomics approaches. Finally, we outline important next steps for an integrative approach to advance understanding of avian physiological adaptation within species. Addressing the knowledge gaps outlined in this review will contribute to an improved predictive framework that synthesizes environmental, morphological, physiological, and genomic data to assess species specific vulnerabilities to a warming planet.

Collisions with windows remain an important human-related threat to bird survival in urban landscapes. Accurately estimating the magnitude of avian mortality at windows is difficult and may be influenced by many sources of error, such as scavenging of carcasses. Failure to account for removal of carcasses by scavengers can bias estimates of window mortality. We tested the hypothesis that carcass survival depends on local habitat factors known to influence scavenger behavior. Scavenger activity on bird carcasses was documented at 20 buildings in an urban landscape in northwestern Illinois for 1 week during each season of a year. Known-fate models were used to relate carcass survival to local habitat composition and to evaluate temporal variation in survival. We also documented species of scavengers and the timing of scavenging using motion-triggered cameras. Daily carcass survival was greater in winter than during spring, summer, and fall. Survival was related negatively to canopy cover (trees and shrubs within a 50-m buffer) and window area, and positively to pavement cover. Using an exponential model of survival time, estimated mean time of survival of carcasses (t ± SE) was 82.9 ± 11.7 d for winter and 11.8 ± 7.2 d for other seasons. Raccoons (Procyon lotor )s cavenged more carcasses than other species. Our results suggest that (1) carcass survival times may be short at locations with preferred habitats of known scavengers and predictable sources of food, and (2) knowledge of scavenger distribution and activity can inform predictive models of persistence. In studies of bird-window collisions, the influence of scavenger bias can be minimized by maintaining short time intervals between carcass searches. Search intervals can be inferred by estimating the number of days that a carcass should persist at a site, which can be calculated using predicted daily survival probabilities of carcasses at study buildings.