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Prior to the emergence of the A/goose/Guangdong/1/1996 (Gs/GD) H5N1 influenza A virus, the long-held and well-supported paradigm was that highly pathogenic avian influenza (HPAI) outbreaks were restricted to poultry, the result of cross-species transmission of precursor viruses from wild aquatic birds that subsequently gained pathogenicity in domestic birds. Therefore, management agencies typically adopted a prevention, control, and eradication strategy that included strict biosecurity for domestic bird production, isolation of infected and exposed flocks, and prompt depopulation. In most cases, this strategy has proved sufficient for eradicating HPAI. Since 2002, this paradigm has been challenged with many detections of viral descendants of the Gs/GD lineage among wild birds, most of which have been associated with sporadic mortality events. Since the emergence and evolution of the genetically distinct clade 2.3.4.4 Gs/GD lineage HPAI viruses in approximately 2010, there have been further increases in the occurrence of HPAI in wild birds and geographic spread through migratory bird movement. A prominent example is the introduction of clade 2.3.4.4 Gs/GD HPAI viruses from East Asia to North America via migratory birds in autumn 2014 that ultimately led to the largest outbreak of HPAI in the history of the United States. Given the apparent maintenance of Gs/GD lineage HPAI viruses in a global avian reservoir; bidirectional virus exchange between wild and domestic birds facilitating the continued adaptation of Gs/GD HPAI viruses in wild bird hosts; the current frequency of HPAI outbreaks in wild birds globally, and particularly in Eurasia where Gs/GD HPAI viruses may now be enzootic; and ongoing dispersal of AI viruses from East Asia to North America via migratory birds, HPAI now represents an emerging disease threat to North American wildlife. This recent paradigm shift implies that management of HPAI in domestic birds alone may no longer be sufficient to eradicate HPAI viruses from a given country or region. Rather, agencies managing wild birds and their habitats may consider the development or adoption of mitigation strategies to minimize introductions to poultry, to reduce negative impacts on wild bird populations, and to diminish adverse effects to stakeholders using wildlife resources. The main objective of this review is, therefore, to provide information that will assist wildlife managers in developing mitigation strategies or approaches for dealing with outbreaks of Gs/GD HPAI in wild birds in the form of preparedness, surveillance, research, communications, and targeted management actions. Resultant outbreak response plans and actions may represent meaningful steps of wildlife managers toward the use of collaborative and multi-jurisdictional One Health approaches when it comes to the detection, investigation, and mitigation of emerging viruses at the human-domestic animal-wildlife interface.

In spite of potential advantages for aircraft structures, composite laminates can be subjected to bird-strike hazard in civil aviation. For purpose of future surrogate experiments, in this study, impact-damage equivalency for twisted composite blades is numerically investigated by Smoothed Particle Hydrodynamics (SPH) and finite element method (FEM). Cantilever slender flat plates are usually used for basic impact tests, the impact-damage equivalency is being considered by comparing damage modes and energies of three impact configurations: (1) twisted blade; (2) flat blade (axisymmetric); and (3) inclined flat blade (centrosymmetric). The damage maps and energy variations were comparatively investigated. Results indicate that both symmetrical flat and inclined flat blades can be, to a certain extent, regarded as alternatives for real twisted blades under bird impact; however, both types of blade have their own merits and drawbacks, and hence should be used carefully. These results aim to serve as tentative design guideline for future prototype or model experimental study of laminated blades in real aeronautical structures.

Birdwatching is considered one of the fastest growing nature-based tourism sectors in the world. Tourists who identify as birdwatchers tend to be well-educated and wealthy travellers with a specific interest in the places they visit. Birdwatchers can bring economic resources to remote communities diversifying their economies and contribute to biodiversity conservation in areas of bird habitat with global significance. Alaska plays a critical role in understanding the link between bird conservation and bird tourism as it supports the world’s largest concentration of shorebirds and is a global breeding hotspot for hundreds of migratory species, including many species of conservation concern for their decline across their ranges. Alaska is also a global destination for birders due to the large congregations of birds that occur during the spring, summer and fall seasons. Despite its global importance, relatively little information exists on the significance of bird tourism in Alaska or on opportunities for community development that align with conservation. This study used ebird data to look at trends in Alaska birdwatching and applied existing information from the Alaska Visitor Statistics Program to estimate visitor expenditures and the impact of that spending on Alaska’s regional economies. In 2016, nearly 300,000 birdwatchers visited Alaska and spent $378 million, supporting approximately 4,000 jobs. The study describes bird tourism’s contributions to local jobs and income in remote rural and urban economies and discusses opportunities for developing and expanding the nature-based tourism sector. The study points toward the importance of partnering with rural communities and landowners to advance both economic opportunities and biodiversity conservation actions. The need for new data collection addressing niche market development and economic diversification is also discussed.

The world’s warm deserts are predicted to experience disproportionately large temperature increases due to climate change, yet the impacts on global desert biodiversity remain poorly understood. Because species in warm deserts live close to their physiological limits, additional warming may induce local extinctions. Here, we combine climate change projections with biophysical models and species distributions to predict physiological impacts of climate change on desert birds globally. Our results show heterogeneous impacts between and within warm deserts. Moreover, spatial patterns of physiological impacts do not simply mirror air temperature changes. Climate change refugia, defined as warm desert areas with high avian diversity and low predicted physiological impacts, are predicted to persist in varying extents in different desert realms. Only a small proportion (<20%) of refugia fall within existing protected areas. Our analysis highlights the need to increase protection of refugial areas within the world’s warm deserts to protect species from climate change. Desert-dwelling species are adapted to high temperatures, but further warming may push them beyond their physiological limits. Here, the authors integrate biophysical models and species distributions to project physiological impacts of climate change on desert birds globally and identify potential refugia.

With the frequent occurrence of bird strikes, minimizing the impact damage effect of birdstrike on flight always is the goal of airworthiness certification. As a large windward component in front of the aircraft, the windshield, and frame have more probability to be suffered from birdstrike. This paper introduces the common connection forms of the windshield frame structure of civil aircraft, and through the interpretation of the airworthiness requirements related to windshield in CCAR-25, puts forward the process and method of compliance verification of windshield frame birdstrike. Based on the SPH method, the dynamic analysis of bird impact on windshield window frame is carried out, the test is carried out to verify that the analysis method is reasonable and conservative, and the results show that the bird impact performance of the windshield frame structure meets the airworthiness requirements.

This study initially conducted bird strike tests and numerical simulations on hollow plates with the Warren structure. The plates manifested notable plastic deformation devoid of fracture. The simulated deformations and strain data of the plates closely corresponded with the outcomes of bird strike impact tests, thereby validating the employed bird strike simulation methodology in this study. Subsequently, while maintaining the outer dimensions of the hollow plate constant, an investigation into the structural parameters of the hollow plate was conducted. Correlations between the thickness of the outer panel, thickness of the Warren, angle of the Warren, and the anti-bird-strike performance of the hollow plate structure were established. The research findings offer valuable insights for informing the design of bird strike resistance in engine blades and hollow plates.

Avian perching maneuvers are one of the most frequent and agile flight scenarios, where highly optimized flight trajectories, produced by rapid wing and tail morphing that generate high angular rates and accelerations, reduce kinetic energy at impact. While the behavioral, anatomical, and aerodynamic factors involved in these maneuvers are well described, the underlying control strategies are poorly understood. Here, we use optimal control methods on an avian-inspired drone with morphing wing and tail to test a recent hypothesis derived from perching maneuver experiments of Harris’ hawks that birds minimize the distance flown at high angles of attack to dissipate kinetic energy before impact. The resulting drone flight trajectories, morphing sequence, and kinetic energy distribution resemble those measured in birds. Furthermore, experimental manipulation of the wings that would be difficult or unethical with animals reveals the morphing factors that are critical for optimal perching maneuver performance of birds and morphing-wing drones. Birds’ agile perching maneuvers allow large energy dissipation in short approach flights. Here, authors test an objective that birds are hypothesized to employ in perching maneuvers on an avian-inspired drone and find that it mimics the birds’ behavior, enabling exploration of key morphing actuations.

Civil aircraft have specific requirements for the anti-bird strike performance of the structure, so the installation of various types of antennas must carry out bird strike assessment to avoid catastrophic consequences because of bird strikes. In this paper, the anti-bird strike performance of a civil aircraft equipped with an antenna is studied by numerical calculation. It shows that the antenna adapter may be plastically deformed after a bird strike, but it will not be damaged or fall off from the body structure as a whole. Therefore, the satcom antenna will not cause catastrophic consequences after a bird strike and meet the airworthiness requirements.

In recent years, the number of birds along the 10kV transmission lines in the northwest region has gradually increased, leading to a rise in the number of transmission line faults caused by bird activities. Bird activities have become one of the factors contributing to bird-related trip faults. By constructing different working conditions of bird activities, this study simulates and analyzes the impact characteristics of the spatial electric field under different conditions within the same spatial range. A spherical air domain is established, and the electric field strength under different conditions is extracted to obtain the electric field distortion rate. By comparing the electric field distortion rates under different conditions, it is found that the number of birds is positively correlated with the spatial electric field distortion rate. Comparing the maximum electric field strength in the air domain with the breakdown field strength of air 3E6V/m, it is observed that bird activities cause spatial electric field distortion, and the maximum spatial electric field strength 4.6391E6V/m exceeds the air breakdown field strength 3E6V/m. This can lead to phase-to-phase short-circuit faults caused by birds. To mitigate the impact of bird activities on transmission lines, this study proposes the installation of insulating sleeves on bare transmission conductors. Simulation results show that after installing the insulating sleeves, the maximum spatial electric field strength 1.0663E6V/m is significantly lower than the air breakdown field strength 3E6V/m. The findings of this study provide a basis for bird protection measures on transmission lines.

Despite the well-established links between air pollution and human health, vegetation, and aquatic ecosystems, less attention has been paid to the potential impact of reactive atmospheric gases and aerosols on avian species. In this literature review, we summarize findings published since 1950 regarding avian responses to air pollution and discuss knowledge gaps that could be addressed in future studies. We find consistent evidence for adverse health impacts on birds attributable to exposure to gas-phase and particulate air pollutants, including carbon monoxide (CO), ozone (O3), sulfur dioxide (SO2), smoke, and heavy metals, as well as mixtures of urban and industrial emissions. Avian responses to air pollution include respiratory distress and illness, increased detoxification effort, elevated stress levels, immunosuppression, behavioral changes, and impaired reproductive success. Exposure to air pollution may furthermore reduce population density, species diversity, and species richness in bird communities.