摘要: The Ashy-headed Laughingthrush(Argya cinereifrons), a species endemic to Sri Lanka, has been historically considered a laughingthrush in the genus Garrulax. However, based on phylogenetic evidence, recent studies have suggested a new classification for the species under the genus Argya(true babblers). Despite the genetic signal showing affinity to true babblers Argya, as its common name suggests, the Ashy-headed Laughingthrush(AHLT) shows remarkable morphological similarities to other laughingthrushes of the Indo-Himalayan region. Here we attempted to address this incongruence in phenotypic and phylogenetic signals in this species by reconstructing the molecular phylogeny of babblers and comparing that with the key morphological, plumage, and vocal features of the two concerned groups. We hypothesized that the convergence of phenotype and vocalization of Garrulax in the wet evergreen forests of the Indian mainland and AHLT in the wet tropical rainforests of southern Sri Lanka has historically confused the taxonomists. The phylogenetic relationships were reconstructed using Bayesian inference using four mitochondrial and seven nuclear gene regions. The molecular phylogenetic tree placed the AHLT with India's Large Grey Babbler(A. malcolmi) as the sister taxon within the genus Argya. The hierarchical clustering based on body size, shape, plumage colour, and vocal properties resulted in the inconsistent placement of ALTH with babblers or laughingthrushes. Therefore, an incongruence in phenotype and genotype is observed. Our findings show that the convergent patterns of phenotypic evolution can confuse both historic and recent taxonomic delimitations in highly divergent groups such as Asian babblers.

摘要: Understanding the evolutionary processes that influence the distribution of genetic diversity in natural populations is a key issue in evolutionary biology. Both species' distribution ranges and environmental gradients can influence this diversity through mechanisms such as gene flow, selection, and genetic drift. To explore how these forces interact, we assessed neutral and adaptive genetic variation in three widely distributed and two narrowly distributed bird species co-occurring along the Cauca River canyon in Antioquia, Colombia—a region of pronounced environmental heterogeneity. We sampled individuals across eight sites spanning the canyon's gradient and analyzed genetic diversity and structure using microsatellites and toll-like receptors(TLRs), a gene family involved in innate immunity. Widely distributed species consistently exhibited higher genetic diversity at both marker types compared to their narrowly distributed counterparts. Although we did not find a significant relationship between microsatellite heterozygosity and TLR heterozygosity, we evidenced a negative trend for widely distributed species and a positive trend for narrowly distributed species. This result suggests that there is a stronger effect of genetic drift in narrowly distributed species. Our results highlight the role of distribution range in maintaining genetic diversity and suggest that environmental gradients, by interacting with gene flow and selection, may influence patterns of adaptive variation.

摘要: Under natural conditions, organisms regularly experience seasonal or unpredictable fluctuations in their diet that may shape the quantity and quality of their reproduction. While these dietary shifts are known to influence overall reproductive output, their specific effects on the proportional composition of egg components remain unexplored. To partially simulate the natural conditions, we conducted two trials using adult Japanese Quails(Coturnix japonica) to examine how dietary restriction and unpredictable feeding influence the proportional composition of egg components. In the first trial, quails were assigned to one of four treatments: full-fed(control) or restricted feeding at 20%(DR20), 30%(DR30), and 40%(DR40) below daily intake. In the second trial, quails were assigned to one of three treatments: full feeding(control), constant 40% restriction(DR40), or unpredictable feeding schedule(UNPR). Each trial lasted for 14 days, and birds were housed individually. Severe dietary restrictions(DR30, DR40) reduced albumen and shell mass, shell thickness, and egg volume. However, yolk mass, yolk color, egg shape index, and shell density remained unaffected across all dietary levels. Severe restrictions also increased the yolk ratio while reducing the albumen ratio, suggesting that birds may evolutionarily prioritize yolk deposition to sustain reproductive functions. However, reduced albumen content due to maternal nutritional stress may also limit essential nutrients, and disrupt the embryo's osmoregulation, which ultimately affects offspring quality. Reduced shell contents at the severe restriction levels can affect the egg's ability to provide physical protection, regulate gas exchange and control water loss, thereby influencing embryonic development. In contrast, moderate restriction(DR20) and unpredictable feeding(UNPR) had no effect on any of the egg traits. These findings suggest that quails strategically allocate resources among egg components under dietary constraints, indicating potential trade-offs in reproductive investment. The resilience observed under moderate restriction and unpredictability underscores the species' adaptive capacity in fluctuating environments.

摘要: Non-selective hunting of waterbirds poses a significant challenge in biodiversity-rich areas such as Important Bird Areas(IBAs), where protected and game species congregate. Here, we present evidence from three consecutive hunting seasons spanning autumn 2021 to spring 2024 at a Natura 2000 site in western Poland, based on analyses of hunting bag photographs, local hunting records, and standardized bird monitoring data. We recorded 1331 hunted individuals from 14 species, 43% of which are protected under national or EU legislation. Among these was the Vulnerable Common Pochard(Aythya ferina), listed on the IUCN Red List. For nearly all species, harvest rates exceeded the sustainable thresholds defined by Bird Life International. Statistical comparisons between species' environmental abundance and their representation in hunting bags indicated no selectivity in shooting, pointing to indiscriminate hunting practices. Simultaneous waterbird monitoring(2018–2024) revealed steep declines in the local waterbird community and a marked decrease in Common Crane(Grus grus) numbers, with average autumn roost counts dropping from over 2000 individuals prior to hunting to 320 during hunting seasons. Although causality cannot be directly confirmed, these patterns suggest substantial disturbance effects. Our findings demonstrate the impracticality of selective hunting in species-rich wetland refuges and highlight the systematic killing of protected species. We recommend banning waterbird hunting in IBAs and implementing mandatory bird identification training and certification for hunters to reduce unintended impacts on vulnerable species.

摘要: Ensuring food security for a rapidly growing global population amidst resource limitations and climate change is a major challenge. Agroforestry an ecologically sustainable land-use system that integrates trees, crops, and sometimes livestock offers significant promise by enhancing biodiversity, ecosystem services, and agricultural productivity. A central concern in such systems is pest management, which traditionally relies on chemical pesticides. However, their excessive use has led to environmental degradation, pest resistance, and health hazards. This review explores the potential of insectivorous birds as natural pest control agents in agroforestry systems. It focuses on how habitat features, vegetation complexity, and species-specific behaviors influence birdmediated biological control. Insectivorous birds manage pest populations through direct predation, targeting a range of insect pests including caterpillars, beetles, and grasshoppers. Their foraging activity helps maintain pest populations below the economic threshold. Vegetation strata comprising ground cover, shrubs, understory, and canopy offer diverse foraging niches and nesting habitats that enhance bird diversity and functional roles. Pest control efficiency is closely linked to seasonality, resource availability, and habitat structure. Differentiating between beneficial(predatory) and pestiferous birds is essential to maximize ecosystem services and minimize crop losses or damage to beneficial insects. Conservation of beneficial bird species, informed vegetation planning, and regular monitoring are vital to strengthening multitrophic interactions and achieving sustainable pest control. Future research should focus on bird behavior, predator-prey interactions, and habitat management to optimize bird-friendly pest regulation strategies in agroforestry landscapes.

摘要: Green cover and human disturbance are important local factors shaping urban bird communities, while climatic and topographic variables can be important when analyzing cities in different biomes. However, the roles of large-scale and local variables influencing bird species composition have been scarcely explored in urban areas. This study aimed to analyze the association of climatic, topographic, landscape, and local variables with bird species composition in streets dominated by buildings and urban parks. I expected park bird composition to be more related to large-scale variables, whereas bird species in streets to be more associated with local-scale variables. Bird surveys were conducted in nine cities along a climatic and topographic gradient. Bird species composition in urban parks and streets were related to climatic and topographic variables, local vegetation greenness, and distance to non-urban areas. However, bird composition in streets was also related to noise and pedestrian traffic. The classification of bird composition in urban parks aligned with the phytogeographic provinces, whereas the streets' bird composition was unrelated to phytogeographic provinces. The results showed that urban habitats with increased vegetation cover allow the colonization of native bird communities and are more aligned with natural large-scale environmental gradients. In contrast, more urbanized sites are decoupled from climatic and topographic gradients and invaded by exotic and widespread native species.

摘要: Urban green spaces and parks offer opportunities for retaining and increasing bird richness, diversity, and species abundance. However, urbanisation influences predator–prey interactions, leading to high predation rates in urban areas, in the UK notably through the presence of large populations of domestic cats and increased populations of synanthropic species, such as rats and squirrels. These high predation rates are assumed to be a significant cause of reproductive failure in birds. Some ecologists advocate for the use of buffer zones with reduced human influence to reduce potential hunting pressure in eco-sensitive areas. However, the buffer effect on predation rates of nesting birds in suburban areas is rarely investigated. In this study, we investigated how edge effects(how close nest sites are to housing) and nest height(i.e., ground vs. above-ground) affected nest predation rates in a suburban park using camera traps to monitor artificial nests containing quail eggs. Our hypothesis was that nests in the buffer area(<300 m inward from university boundary) and at low height would suffer higher predation rates than nests in the core area(>300 m from the university boundary) and at height, as the buffer zone effect, and ease of access to ground predators would result in higher predation rates. We found no significant effect of nest height in nest predation rates. However, contrary to our expectations, nests in the core zone suffered higher predation rates than those in the buffer zone, and corvids were responsible for almost half of the egg loss events. We speculate that this may be a consequence of higher levels of anthropogenic disturbance(e.g., pedestrians, dog walking, vehicles) adjacent to our buffer zone acting as a deterrent to avian nest predators. This work suggests that protecting urban sites from disturbance may not always act to support bird abundance.

摘要: Roads are a leading cause of habitat fragmentation and may reduce bird populations by increasing nest predation rates. However, few studies have investigated the effects of traffic volume on the reproductive success of roadside birds in the neotropics. Our goal was to evaluate the effects of spatial, temporal, and vehicle flow variations on the survival of artificial open-cup nests. The study was carried out in a nature reserve on the side of a highway during the breeding season(from October to March) in two restinga(sand-coastal plain) phytophysiognomies in southeastern Brazil: non-floodable(open) and floodable(closed). One hundred thirty nests were distributed along transects ranging from 3 m to 300 m from the highway in each vegetation type(totaling 260 nests). The nests were checked every three days for their status(depredated or intact) over 12 days, and new nests were subsequently placed near sampling points of depredated or successful nests. We estimated survival using logistic exposure generalized linear and additive mixed models. At the end of the 180 days of the experiment, 33% of 6202 nests were successful. Nest survival was higher in open restinga than in closed restinga. In both habitats, nest survival was lowest mid-season and highest at the beginning and end. Survival rates peaked near the highway, declined up to 50 m away, then showed a slight increase. Finally, survival increased at moderate-tohigh traffic volumes(～22,000 vehicles/day), particularly in open restinga. We suggest that spatial, temporal, and habitat-specific highway impacts(e.g., noise, vibration, visual stimuli) can lead to variations in the activity of nest predators, generating fluctuations in nest survival associated with predator behavior.

摘要: The factors affecting the behavior of non-specialized nectar-feeding passerines have received little attention in the literature on plant-pollinator interactions. Puya chilensis(Bromeliaceae) has sterile branch apices that project outward from the inflorescence. In this study, we evaluate the functional role of sterile apices as support systems for bird foraging behavior. We recorded bird visitation and flower probing in the presence and absence of sterile branches during the spring seasons of 2021 and 2024. The results revealed that experimental plants with excised branches received fewer bird visits and flower probings than control plants, indicating that sterile branches play an important role in the nectar-feeding behavior of passerine birds in P. chilensis.

摘要: With the ongoing acceleration of global urbanization, an increasingly larger proportion of natural habitats are being transformed and utilized by humans. Urbanization has a substantial impact on animal populations, exposing them to greater risks, but also presenting new opportunities and resources. Although the effects of urbanization and brood parasitism on the population dynamics and behavior of host birds have received considerable attention, there has been comparatively little research on how urbanization might affect the risk of brood parasitism on host birds. From April to August in 2023 and 2024, we investigated the risk of brood parasitism on Azure-winged Magpies(Cyanopica cyanus) breeding in the urban center, outskirt, and rural areas of Wuhan City, Hubei Province, China. The results revealed significant differences in the risk of brood parasitism among Azure-winged Magpies in the three regions, with the proportion of magpies parasitized by the Asian Koel(Eudynamys scolopaceus) being found to be significantly lower in the city center(0%) than that in outskirt(3.8%) and rural(11.4%) areas. Our results are consistent with the idea that cities can act as refuges that reduce the risk of brood parasitism experienced by host Azure-winged Magpies. Accordingly, breeding in cities enables Azurewinged Magpies to escape brood parasitism by the Asian Koel.