Search Results (319)

With worldwide development of wind energy, birds have grown increasingly vulnerable to collisions with wind turbines. For several species of eagles, which in many countries are accorded special protection due to a host of anthropogenic threats, accurate estimates of collision mortality are needed to assess impacts and to formulate appropriate mitigation strategies. Unfortunately, estimates of wind turbine collision mortality are often biased low by failing to account for carcasses that fall beyond the fatality search area boundary, B. In some instances, carcass density is modeled across the fatality search area to adjust for these undetected fatalities. Yet for more accurate fatality estimates, it is important to determine $\widehat{B}$, the search area boundary within which all carcasses could be found. We used eagle carcass data from multi-year fatality studies conducted at the Island of Smøla, Norway, and the Altamont Pass Wind Resource Area, California, USA, to assess carcass density (i) as a contributor to mortality estimation (ii) as a predictor variable of B, and (iii) to test whether the cumulative carcass counts with increasing distance from the wind turbine can predict $\widehat{B}$. We found that carcass counts within 5 m annuli change little with increasing distance from modern wind turbines, and that carcass density is largely a function of the area calculated. Characterization of the spatial distribution of carcasses within the search area varies with the search radius that determines B. However, this may not represent the true spatial distribution of carcasses, including those found beyond B. We assert that the available data are unsuitable for predicting the number of eagle carcasses within and beyond a given search area, nor for determining $\widehat{B},$ but they do indicate that $\widehat{B}$ lies much farther from wind turbines than previously assumed. Ultimately, modeling available carcass distribution data cannot replace the need for searching farther from wind turbines to account for the true number of eagle collision victims at any given wind project. Full article

Urban soundscapes are increasingly recognized as fundamental for both ecological integrity and human well-being, yet the complex interplay between the vegetation structure, seasonal dynamics, and microclimatic factors in shaping these soundscapes remains poorly understood. This study tests the hypothesis that vegetation structure and seasonally driven biological activity mediate the balance and the quality of the urban acoustic environment. We investigated seasonal and spatial variations in five acoustic indices (NDSI, ACI, AEI, ADI, and BI) within a historical urban garden in Castelfranco Veneto, Italy. Using linear mixed-effects models, we analyzed the effects of season, microclimatic variables, and vegetation characteristics on soundscape composition. Non-parametric tests were used to assess spatial differences in vegetation metrics. Results revealed strong seasonal patterns, with spring showing increased NDSI (+0.17), ADI (+0.22), and BI (+1.15) values relative to winter, likely reflecting bird breeding phenology and enhanced biological productivity. Among microclimatic predictors, temperature (p < 0.001), humidity (p = 0.014), and solar radiation (p = 0.002) showed significant relationships with acoustic indices, confirming their influence on both animal behaviour and sound propagation. Spatial analyses showed significant differences in acoustic patterns across points (Kruskal–Wallis p < 0.01), with vegetation metrics such as tree density and evergreen proportion correlating with elevated biophonic activity. Although the canopy height model did not emerge as a significant predictor in the models, the observed spatial heterogeneity supports the role of vegetation in shaping urban sound environments. By integrating ecoacoustic indices, LiDAR-derived vegetation data, and microclimatic parameters, this study offers novel insights into how vegetational components should be considered to manage urban green areas to support biodiversity and foster acoustically restorative environments, advancing the evidence base for sound-informed urban planning. Full article

Skin color is a crucial phenotypic trait in poultry that influences consumer preference, market value, and breed identification. However, the mechanisms underlying skin color variation in Lingshan chickens remain poorly understood. This study aimed to elucidate the physiological, metabolic, and microbial characteristics associated with skin color differences in male Lingshan chickens. A total of 210 castrated male Lingshan chickens were categorized into white-shanked (WS), yellow-shanked (YS), and red-shanked (RS) groups based on the Roche color fan scores. The results showed that chickens in the YS and RS groups exhibited significantly higher body weights and pigmentation levels in the shank, breast, and abdominal skin compared to those in the WS group (p < 0.05). Serum concentrations of triglycerides (TG), total cholesterol (TC), high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very-low-density lipoprotein (VLDL) were markedly elevated in RS chickens. Additionally, carotenoid profiles revealed higher deposition of lutein and β-carotene in the skin and adipose tissues of YS and RS birds. Gene expression analysis indicated differential regulation of carotenoid transport and metabolism-related genes among groups. Furthermore, 16S rRNA sequencing of cecal microbiota revealed significant compositional shifts in microbial communities associated with shank pigmentation. Collectively, these findings suggest that differences in shank color in Lingshan chickens are closely linked to lipid metabolism, carotenoid transport, and gut microbiota composition. This study provides novel insights into the biological mechanisms driving skin pigmentation, offering valuable implications for breeding and functional trait selection in indigenous chicken populations. Full article

Rapid urbanization has resulted in widespread habitat loss and fragmentation, threatening global biodiversity. Urban parks serve as essential refuges for wildlife within cities, particularly for birds, which are sensitive indicators of ecosystem health and habitat quality. In recent years, numerous Chinese cities have begun integrating biodiversity-friendly design approaches into new park development. However, the effectiveness of these strategies remains insufficiently evaluated. This study assesses the ecological performance of newly built parks by examining 11 recently constructed parks (within the past decade) and 9 historical parks in Zhengzhou, China’s high-density urban area. Monthly bird surveys were conducted across all 20 parks from May to December 2020, covering breeding, post-breeding, and overwintering seasons. Our findings reveal that new parks significantly outperformed old parks in bird abundance, species richness, Shannon diversity index, and functional diversity. Analysis of environmental variables at both local (within-park) and landscape (1-km buffer) scales showed that habitat diversity and multi-layered vegetation structure were the most influential local factors promoting bird diversity, while green space connectivity was the primary landscape-scale contributor. Notably, neither park area nor age significantly predicted diversity patterns. Based on these results, we propose three key planning strategies: (1) enhancing habitat diversity within parks to support species from various ecological niches; (2) implementing multi-layered vegetation planting to provide diverse food resources and nesting opportunities; (3) improving green space connectivity to facilitate species movement and population persistence within urban environments. These findings provide valuable insights for designing more effective biodiversity-friendly urban green spaces. Full article

H1N1 influenza, also known as swine flu, is a subtype of the influenza A virus that can infect humans, pigs, and birds. Sensitivity analysis and optimal control studies play a crucial role in understanding the dynamics of H1N1 influenza. In this study, we have derived a mathematical model incorporating both symptomatic and asymptomatic infections, as well as vaccination, to assess the impact of key parameters on disease transmission. Also, we have assumed a density-dependent infection transmission in the modeling process of H1N1 dynamics. We determine the basic reproduction number using the next-generation matrix method and found that the disease-free equilibrium is stable when the basic reproduction number $R_0<1$ and the endemic equilibrium exists and is stable globally when $R_0>1$. By performing sensitivity analysis, the most influential factors affecting infection spread are identified, aiding in targeted intervention strategies. Optimal control techniques are then applied to determine the best approaches to minimize infections while considering resource constraints. The findings provide valuable insights for public health policies, offering effective strategies for mitigating H1N1 outbreaks and enhancing disease management efforts using optimal vaccination. Full article

Bird–plant interactions are critical for maintaining biodiversity and ecosystem function, and represent a key research focus in modern ecology. Using the line transect method, we surveyed bird diversity and collected plant trait data in four habitat types in the southern zone of Fujian’s Meihuashan National Nature Reserve during October–December 2021 and July–August 2022. This study investigated how plant traits (tree height, diameter at breast height (DBH), canopy density fruit amount) influence the diversity of frugivorous birds (species richness, abundance, Shannon–Wiener, Pielou, Simpson) across four disturbed habitats—villages (residential areas), bamboo forests (economic plantations), unguarded broad-leafed forests (wild forests), and nurtured broad-leafed forests (managed forests)—during both summer (breeding season) and autumn–winter (fruiting season). The key findings revealed that (1) significant correlations between plant traits and bird diversity were exclusive to the fruiting season, with no associations found in summer; (2) during autumn–winter, the key plant traits driving bird diversity varied distinctively by habitat: tree height and canopy density were paramount in villages; both habitat structure (canopy density) and fruit amount were important in bamboo forests, whereas in both broad-leafed forests, a combination of tree structure (height, DBH, canopy density) and fruit amount determined bird abundance; (3) a significant interaction between season and habitat was detected for community evenness, indicating that habitat type modulates the seasonal effects on community composition. This study underscores that in human-modified landscapes, conserving habitat structural complexity and key resource plants is crucial for sustaining frugivorous bird diversity and its ecological functions. Conservation strategies must account for seasonal dynamics to be effective. Full article

The marine environment has long been affected by chronic operational oil pollution, leading to the deaths of hundreds of thousands of seabirds. In many countries Beached Bird Survey programmes have been established, in which dead birds with oil-contaminated plumage are counted along shorelines. This study analyses data from Beached Bird Surveys conducted in the western Gulf of Gdańsk (southern Baltic Sea) between 1965/66 and 2024/25 to assess long-term trends in oil pollution. Over a total of 55 seasons, 12,264 dead birds representing 49 different species were recorded, of which 2748 individuals (22%) had oiled plumage. The oil rate was very high up to the 1977/78 season, ranging from 58% to 95%. During that period, the highest densities of oiled birds were also recorded, with values exceeding 20 individuals. A significant decline in the number of oiled birds occurred in the early 1980s, and, apart from two anomalous seasons in the mid-1990s, numbers have remained low since then. This sharp drop coincides with the enforcement of MARPOL regulations and the introduction of regular aerial surveillance to detect oil spills and identify violators. The resulting reduction in ship-based pollution has supported more sustainable use of this ecologically important marine region. The findings highlight the effectiveness of international regulations and monitoring efforts in reducing chronic oil pollution and improving the health of the Baltic Sea ecosystem. Full article

Excessive use of antibiotic growth promoters (AGPs) in broiler rearing has led to severe issues due to antimicrobial resistance and drug residues in meat. This study was conducted to evaluate aqueous Moringa oleifera leaf extract (MOLE) as a natural alternative to antibiotics in broiler chickens. 150 broiler chicks were randomly distributed into five groups: one control, three MOLE-treated groups (60, 90, and 120 mL/L), and one Enrofloxacin-treated group (an antibiotic). The birds were monitored for a 35-day trial period, split further into a starter phase (0–21 days) and a finisher phase (22–35 days). The results were that at the starter phase of their lives, birds treated with MOLE120 experienced better body weight gain and optimal feed conversion ratio (FCR), which showed improved early growth performance. In the finisher phase, the MOLE90 group demonstrated the best FCR and a favorable weight gain, showing better efficiency at later stages. Crude protein digestibility was highest in the MOLE90 group (69.97%), and apparent metabolizable energy also increased in all MOLE-treated groups, especially MOLE120 (2938.9 kcal/kg). Regarding the blood lipid profile, the MOLE90 group had the lowest low-density lipoprotein (LDL) (82.3 mg/dL) and cholesterol (181.7 mg/dL), while MOLE120 achieved the highest high-density lipoprotein (HDL) level (92.6 mg/dL) with significant (p < 0.05) effects across all parameters. Triglycerides were slightly higher in MOLE groups but remained within physiological limits. In conclusion, MOLE supplementation, particularly at 90–120 mL/L, improved performance and blood lipid metabolism in a phase-specific manner. MOLE120 was more effective in early growth, while MOLE90 proved optimal in the finishing stage. This study supports the potential of MOLE as a phytogenic substitute for antibiotics in poultry production. Full article

Particle Swarm Optimization (PSO) is a metaheuristic optimization technique based on population behavior, inspired by the movement of a flock of birds or a school of fish. In this method, particles move in a search space to find the global minimum of an objective function. In this work, a modified PSO algorithm written in Fortran 90 is proposed. The optimized structures obtained with this algorithm are compared with those obtained using the basin-hopping (BH) method written in Python (3.10), and complemented with density functional theory (DFT) calculations using the Gaussian 09 software. Additionally, the results are compared with the structural parameters reported from single crystal X-ray diffraction data for carbon clusters ${\mathrm{C}}_n$(n = 3–5), and tungsten–oxygen clusters, ${\mathrm{WO}}_n^{m-}$(n = 4–6, $m=2,4,6$). The PSO algorithm performs the search for the minimum energy of a harmonic potential function in a hyperdimensional space $\in {\mathbb{R}}^{3N}$ (where N is the number of atoms in the system), updating the global best position ( $g_{best}$) and local best position ( $p_{best}$), as well as the velocity and position vectors for each swarm cluster. A good approximation of the optimized structures and energies of these clusters was obtained, compared to the geometric optimization and single-point electronic energies calculated with the BH and DFT methods in the Gaussian 09 software. These results suggest that the PSO method, due to its low computational cost, could be useful for approximating a molecular structure associated with the global minimum of potential energy, accelerating the prediction of the most stable configuration or conformation, prior to ab initio electronic structure calculation. Full article

Balancing urban nighttime development with biodiversity conservation requires a clear understanding of how artificial light at night (ALAN) affects wildlife over time. However, long-term, fine-scale quantitative assessments remain scarce. Here, we analyzed bird diversity and ALAN in Shanghai from 2000 to 2024 at a 1 km resolution by integrating bird observation records with satellite-derived nighttime light data. We quantified the interaction between bird diversity and ALAN using a coupling coordination degree model (CCDM) and identified key drivers with GeoDetector. Our results show that bird diversity increased in 16% of the study area, though spatially fragmented, while ALAN intensified and expanded outward from the urban core, affecting 4.6% of the area. Areas with moderate or higher coordination (CCD > 0.5) nearly doubled, primarily in urban–suburban transition zones. Urban land use, road density, and vegetation cover (NDVI) were the dominant drivers, with NDVI-related interactions significantly enhancing explanatory power. These findings provide the first long-term, spatially explicit assessment of ALAN–bird diversity interactions in Shanghai, offering quantitative guidance for zoning-based lighting management, green space planning, and biodiversity-friendly urban development. Full article

Atherosclerosis is highly prevalent among captive psittacine populations and is a frequent cause of veterinary consultations. Ante-mortem diagnosis remains challenging, but the serum lipoprotein analysis has been suggested as a useful tool for identifying associated risk factors and improving understanding of its pathogenesis. Unlike in humans, the relationship between lipoproteins and atherosclerosis in parrots has not been clearly established. This retrospective cohort study analyzed n = 1199 blood samples from 692 parrots across 14 genera to establish reference intervals for high-density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C) and non-high-density lipoprotein cholesterol (non-HDL-C) following ASVCP guidelines. Lipoprotein levels were evaluated in relation to factors such as genus, age, sex, diet, reproductive status, body condition score, and atherosclerosis prevalence (diagnosed by endoscopy and/or necropsy). The results demonstrated genus-specific differences and significant associations between LDL-C and atherosclerosis, with non-HDL-C showing a similar, less pronounced, trend. Higher LDL-C values were measured in the presence of moderate-severe atherosclerosis. Birds on seed diets had higher lipoprotein levels and were more likely to be diagnosed with atherosclerosis in comparison to birds fed a pelleted or extruded diet. The role of HDL-C remained less conclusively defined. The results of this study provide a foundational framework for the future use of lipoprotein analysis in parrot medicine, offering novel insights into the management of cardiovascular health in pet parrots. Full article

Suburban forest patches can have important conservation value for birds. This is a hopeful trend because the extent of urbanization is increasing, many avian populations are declining, and urban areas are where most people interact with wildlife. There is evidence that, despite an increased density of potential predators, the breeding success of birds in urban or suburban forest patches is comparable to that in rural areas. However, extremely limited data exists on the fledgling life stage of birds in urban or suburban areas, even though it is known that the fledgling stage strongly influences population growth rates. We used radio telemetry to look at the survival, movement, and habitat use of fledgling Wood Thrushes (Hylocichla mustelina) originating from nests in suburban forest patches and in larger swaths of rural, undeveloped forests in western Massachusetts. We tracked 168 fledglings over four field seasons and found that survival was similar for rural and suburban fledglings. Fledglings had lower mortality as they aged. Force-fledging and being left outside the nest after radio-tagging had a negative effect on survival, and we developed techniques to minimize its occurrence. We also found that rural fledglings moved farther from their natal nests, at any given age, than suburban fledglings. Fledglings in both suburban and rural sites selected denser understory growth, and the use of non-forested land cover increased as they aged. Full article

Avian influenza (AI), particularly the H5 subtypes, poses a significant and persistent threat globally. While the influence of environmental factors on AI seasonality is recognized, a comprehensive understanding of the hierarchical and interactive effects of multi-scale drivers in a vast and ecologically diverse country like China remains limited. We developed an interpretable machine learning framework (XGBoost with SHAP) to analyze the spatiotemporal risk of 1800 H5 AI outbreaks in mainland China from 2000 to 2023. We integrated multi-source data, including dynamic poultry density, Köppen climate classifications, Important Bird and Biodiversity Areas (IBAs), and daily meteorological variables, to identify key drivers and quantify their nonlinear and synergistic effects. The model demonstrated high predictive accuracy (5-fold cross-validation $R^2$ = 0.776). Our analysis revealed that macro-scale ecological contexts, particularly poultry density and specific Köppen climate zones (e.g., Cwa), and strong seasonality were the most dominant drivers of AI risk. We identified significant nonlinear relationships, such as a strong inverse relationship with temperature, and a critical synergistic interaction where high temperatures substantially amplified risk in areas with high poultry density. The final predictive map identified high-risk hotspots primarily concentrated in eastern and southern China. Our findings indicate that H5 AI risk is governed by a hierarchical interplay of multi-scale environmental drivers. This interpretable modeling approach provides a valuable tool for developing targeted surveillance and early warning systems to mitigate the threat of avian influenza. Full article

Biodiversity conservation and sustainable development in high-density forest urban areas have attracted growing attention and are increasingly recognized as critical for achieving the Sustainable Development Goals (SDGs). University campus forests, functioning as ecological islands, possess unique acoustic characteristics and play a vital role in supporting urban biodiversity. In this case study, acoustic monitoring was conducted over the course of a full year to objectively reveal the ecological patterns across temporal scales of the campus sound environment, by combining acoustic indices’ visualization combined with statistical analysis. The findings indicate (1) the existence of ecological sound patterns across different temporal scales, closely associated with phenological cycles; (2) the identification of the specific timing affected by the different species‘ activities, such as the breeding season of birds, the chirping time of cicadas and other insects, as well as the fluctuations in the intensity of human activities, and (3) the development of a methodological framework integrating a visualization technique with statistical analysis to enhance the understanding of long-term ecological dynamics. The results offer a foundation for promoting the sustainable conservation of campus biodiversity in high-density urban settings. Full article

Management for pheasant shooting is a widespread land use in the UK, with potential implications for forest and hedgerow habitats. This study evaluates whether sites managed for pheasant shooting differ ecologically from similar sites not used for shooting. A systematic evidence evaluation of comparative studies was combined with a spatial analysis using remote sensing data (2010–2024). The literature review identified only 32 studies meeting strict criteria for comparability, revealing inconsistent and often weak evidence, with few studies reporting detailed forest management or statistically robust outcomes. While some studies noted increased or decreased biodiversity associated with pheasant shooting, the evidence base was generally of low quality. Remote sensing assessed forest structural and spectral diversity, intactness, and hedgerow density across 1131 pheasant-managed and 1131 matched control sites. Biodiversity data for birds, plants, and butterflies were sourced from GBIF records. Structural diversity and hedgerow density were significantly higher on pheasant-managed sites, while no significant differences were found in forest spectral diversity, intactness, or biodiversity indicators. Pheasant management may shape certain habitat features but has limited demonstrable effects on overall biodiversity. Further field-based, controlled studies are required to understand causal mechanisms and inform ecologically sustainable shooting practices. Full article