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Identifying the processes that limit populations is a foundational objective of ecology and an urgent need for conservation. For migratory animals, researchers must study individuals throughout their annual cycles to determine how environmental conditions limit demographic rates within each period of the annual cycle and also between periods through carry-over effects and seasonal interactions. 1,2,3,4,5,6 Our poor understanding of the rates and causes of avian migration mortality 7 hinders the identification of limiting factors and the reversal of widespread avian population declines. 8,9 Here, we implement new methods to estimate apparent survival (hereafter survival) during migration directly from automated telemetry data 10 in Kirtland's Warblers (Setophaga kirtlandii) and indirectly from mark-recapture data in Black-throated Blue Warblers (S. caerulescens). Previous experimental and observational studies of our focal species and other migratory songbirds have shown strong effects of Caribbean precipitation and habitat quality on food availability, 11,12,13,14 body condition, 12,13,14,15,16,17,18,19 migration timing, 11,12,15,16,20,21,22,23 natal dispersal, 24,25 range dynamics, 26 reproductive success, 20,22,27 and annual survival. 18,19,20,23,28,29,30,31 Building on this research, we test the hypotheses that environmental conditions during the non-breeding period affect subsequent survival during spring migration and breeding. We found that reduced precipitation and environmental productivity in the non-breeding period strongly influenced survival in both species, primarily by reducing survival during spring migration. Our results indicate that climate-driven environmental conditions can carry over to affect survival in subsequent periods and thus likely play an important role in year-round population dynamics. These lethal carry-over effects may be widespread and are likely magnified by intensifying climate change. • New methods allow for direct and indirect estimation of survival during migration • Poor non-breeding conditions affect songbird survival during migration and breeding • Lethal carry-over effects may be widespread in other migratory taxa • Climate change is likely to magnify these effects and endanger animal populations Using new methods to estimate songbird survival during the non-breeding, spring migration, and breeding periods, Cooper et al. show that drought and poor environmental productivity in winter carry over to reduce survival during migration and breeding. These lethal carry-over effects may be widespread and will likely be magnified by climate change. [ABSTRACT FROM AUTHOR]

Aim: Ongoing climate changes represent a major determinant of demographic processes in many organisms worldwide. Birds, and especially long‐distance migrants, are particularly sensitive to such changes. To better understand these impacts on long‐distance migrants' breeding productivity, we tested three hypotheses focused on (i) the shape of the relationships with different climate variables, including previously rarely tested quadratic responses, and on regional differences in these relationships predicted by (ii) mean climatic conditions and (iii) by the rate of climate change in respective regions ranging from Spain to Finland. Location: Europe. Time Period: 2004–2021. Major Taxa Studied: Long‐distance migratory passerine birds. Methods: We calculated breeding productivity from constant effort ringing sites from 11 European countries covering 34° of latitude, and extracted temperature‐ and precipitation‐related climate variables from E‐OBS and NASA MODIS datasets. To test our hypotheses, we fitted GLMM and Bayesian meta‐analytic models. Results: We revealed hump‐shaped responses of productivity to temperature, growing degree‐days, green‐up onset date, and precipitation anomaly, and negative responses to intense and prolonged rains across the regions. The effects of March temperature and April growing degree‐days were more negative in cold than in warm regions, except for the region with the highest accumulated heat, whereas increasing June precipitation anomalies were associated with higher productivity in both dry and wet regions. Productivity responses to climate were unrelated to the rate of climate warming. Main Conclusions: The influence of climate on bird productivity proved to be frequently nonlinear, as expected by ecological theory. The rate of climate change is less important than regional interannual variability in climate (which is predicted to increase), but this may change with the progression of climate change in the future. Productivity declines in long‐distance migratory songbirds are particularly expected if out‐of‐norm water excess increases in frequency or strength. [ABSTRACT FROM AUTHOR]

Since its first isolation from migratory birds in Egypt in 2016, highly pathogenic avian influenza (HPAI) H5N8 has caused several outbreaks among domestic poultry in various areas of the country affecting poultry health and production systems. However, the genetic and biological properties of the H5N8 HPAI viruses have not been fully elucidated yet. In this study, we aimed to monitor the evolution of circulating H5N8 viruses and identify the pathogenicity and mammalian adaptation in vitro and in vivo. Three H5N8 HPAI viruses were used in this study and were isolated in 2021–2022 from poultry and wild birds during our routine surveillance. RNA extracts were subjected to full genome sequencing. Genetic, phylogenetic, and antigenic analyses were performed to assess viral characteristics and similarities to previously isolated viruses. Phylogenetic analysis showed that the hemagglutinin genes of the three isolates belonged to clade 2.3.4.4b and grouped with the 2019 viruses from G3 with high similarity to Russian and European lineages. Multiple basic amino acids were observed at cleavage sites in the hemagglutinin proteins of the H5N8 isolates, indicating high pathogenicity. In addition, several mutations associated with increased virulence and polymerase activity in mammals were observed. Growth kinetics assays showed that the H5N8 isolate is capable of replicating efficiently in mammalian cells lines. In vivo studies were conducted in SPF chickens (White Leghorn), mice, and hamsters to compare the virological characteristics of the 2022 H5N8 isolates with previous H5N8 viruses isolated in 2016 from the first introduction. The H5N8 viruses caused lethal infection in all tested chickens and transmitted by direct contact. However, we showed that the 2016 H5N8 virus causes a higher mortality in chickens compared to 2022 H5N8 virus. Moreover, the 2022 virus can replicate efficiently in hamsters and mice without preadaptation causing systemic infection. These findings underscore the need for continued surveillance of H5 viruses to identify circulating strains, determine the commercial vaccine's effectiveness, and identify zoonotic potential. [ABSTRACT FROM AUTHOR]

Intra‐Africa movements of most African migratory birds remain an enigma. We describe the migrations of Wahlberg's eagle Hieraaetus wahlbergi using GPS‐GSM transmitters on adult eagles in their South African (n = 3) and Kenyan (n = 7) breeding areas between 2018 and 2022. The dataset included 57 migratory tracks, 29 post‐breeding and 28 pre‐breeding. We found long‐distance migrants (LDMs; from South Africa) and short‐distance migrants (SDMs; from Kenya) using common non‐breeding areas centered in the Sudans and Central African Republic. The timing of annual phases was similar, but LDMs departed on their pre‐breeding migration on average later than SDMs (13 August versus 31 July) and arrived later on their breeding grounds (13 September versus 10 August). Conversely, the average departure date on the post‐breeding migration was 4 April for SDM and 23 March for LDMs. LDMs spent significantly less time of the year than SDMs on breeding grounds (44 versus 57%), and slightly but not significantly more time (40 versus 38%) on non‐breeding areas. The post‐breeding migration distance was on average 3413.9 ± 170.9 km for LDMs and 491.9 ± 158.5 km for SDMs. At non‐breeding areas, LDMs reached more northerly latitudes than SDMs, increasing the pre‐breeding migration distance to 4495.9 ± 372.5 km for LDMs versus 1701.9 ± 167.3 for SDMs. Daily flight distances back to the breeding areas averaged 153.4 ± 130.3 km for LDMs and 167.4 ± 122.3 km for SDMs and to non‐breeding areas were shorter for SDMs (124.8 ± 113.0 km) than LDMs (178.0 ± 134.4 km). Migration speed was similar across populations and for pre‐ and post‐breeding migrations. LDMs used more stopover days than SDMs. We conclude that Wahlberg's eagles from different parts of Africa have adapted their migration to differences in timing of the breeding season, distance of travel, and resources in the landscapes encountered during migration. [ABSTRACT FROM AUTHOR]

Bordoibam-Bilmukh is a small wetland located at the boundary of the Dhemaji and Lakhimpur districts of Assam, India that provides shelter and breeding ground to many resident and migratory birds. A survey was conducted between October 2022 and March 2024 on the avian diversity of Bordoibam-Bilmukh Bird Sanctuary. A total of 47 bird species under 16 orders and 29 families were recorded during the survey. Order Passeriformes, recorded with the highest number of avian species (15). Among the families, the highest number of species (5) was recorded under Ardeidae. Out of all the species recorded, three species, viz., Brown Shrike, Citrine Wagtail, and White Wagtail were winter migratory; one species, the Lesser Kestrel, was summer migratory, and the remaining 43 were resident species. Besides, two species, viz., Lesser Adjutant and Greater Adjutant are listed as 'Near Threatened' species on the IUCN Red List. Comparing the avian diversity from 1997 to 2024, a decline in the number of avian species from 167 (as per the 1997 record) to 47 (as per the present study) has been observed in the sanctuary. Various anthropogenic activities such as habitat destruction and disturbance, hunting of birds, are the major causes of the decline of avian diversity. For future species diversity restoration in the sanctuary, these negative anthropogenic activities should be addressed immediately for conservation strategies. [ABSTRACT FROM AUTHOR]

A comprehensive inventory of faunal and floral species in a specific region holds significant value for scientific investigation. This study was conducted between 2015 and 2021, especially during the winter season, in Pakhibitan Bird & Wildlife Sanctuary (also known as Gajoldoba wetland) in West Bengal, which was established in 2016. This wetland surrounded by forests is located on the upper section of the Teesta Barrage in the Dooars region of Jalpaiguri District, and it attracts birds from the Central Asian Flyway. Around 124 bird species belonging to 14 orders and 37 families were documented. Passeriformes with 32 species, and Anatidae with 23 species, are the most abundant groups. Based on the IUCN Red Data Book (2022-23), six species are Near Threatened, four are Vulnerable, and one Endangered. About 50% of birds were resident, 44% migratory, and 6% local migrants. [ABSTRACT FROM AUTHOR]

Changes in the migration phenology of birds linked to global change are extensively documented. Longitudinal studies from temperate breeding grounds have mostly shown earlier arrivals in the spring and a variety of patterns during fall migration, 1,2 yet no studies have addressed whether and how migration phenology has changed using data from the tropical non-breeding grounds. Understanding whether changes in migratory phenology are also evident in non-breeding sites is essential to determining the underlying causes of patterns documented in breeding areas. Using data from historical scientific collections and modern repositories of community science records, we assessed changes in the migration phenology of 12 Nearctic-Neotropical long-distance migratory birds in Colombia over six decades. We also explored whether shared breeding and non-breeding climatic niches explained variation in the phenological patterns observed among species. All species showed shifts in spring (range −37 to 9 days from peak passage date) or fall (range −26 to 36 days) migration, but patterns differed among species in ways partly attributable to shared breeding or wintering climatic niches. Our results, although not yet broadly generalizable, suggest that birds use cues to time their migration at their non-breeding grounds, which are most likely different to those they use on their breeding grounds. To better understand the effects of global change on biodiversity, exploring the underlying drivers of phenological changes with further research integrating more long-term datasets available through scientific collections and community science platforms should be a priority. • Comparison of historical and modern records from non-breeding Neotropical migratory birds • Twelve migratory bird species showed shifts in migration phenology over six decades • Shifts resulted in longer breeding or longer non-breeding periods for some species • Environmental cues driving shifts likely differ in tropical and temperate regions Gutiérrez-Carrillo et al. show phenological shifts in the migration phenology of 12 species of Nearctic-Neotropical migratory birds over six decades, based on data from the non-breeding grounds. Temperate and tropical environmental cues and ecological factors driving phenological shifts in birds are likely different at various stages of the annual cycle. [ABSTRACT FROM AUTHOR]

Migratory birds are a natural reservoir for major respiratory viruses such as the avian influenza virus (AIV) and the avian coronavirus (AvCoV). Transmission of these viruses from migratory birds to domestic birds increases the prevalence of those diseases that cause severe economic and public health concerns in Bangladesh. The study focused on active surveillance of major respiratory viral pathogens in migratory birds, molecular identification of the viruses, and their phylogenetic origin. To conduct this study, 850 environmental samples (830 fecal samples, 10 soil samples, and 10 water samples) were collected during three consecutive winter seasons from three divisions (Dhaka, Sylhet, and Mymensingh) and pooled according to the year of collection and locations, resulting in a total of 184 tested samples. Using gene-specific primers and probes in TaqMan-and SYBR Green-based RT-qPCR assays, the samples were screened for AIV and AvCoV, respectively. Out of the 184 pooled samples, 37 were found to be positive for these respiratory pathogens. Furthermore, out of the 37 (20.11%) positive respiratory pathogens, 11.96% were AIV (n = 22) and 8.15% were AvCoV (n = 15). For the first time in Bangladesh, AIV H4N2, H4N6, and AvCoVs have been found in fecal samples from migratory birds through surveillance. Phylogenetic analyses of the HA and NA genes of AIV and the polymerase gene (Orf 1) of AvCoV revealed that these strains share a close phylogenetic relationship with the isolates from wild birds in Europe and Asia. The Bangladeshi strains with Eurasian ancestry might pose a significant threat to migratory birds flying through the Asian flyways. They might also be a potential source of virus introduction and spread to poultry raised on land. These findings emphasize the significance of ongoing AIV and AvCoV surveillance in migratory birds in Bangladesh. [ABSTRACT FROM AUTHOR]

Multidrug resistance (MDR) considered as global crisis facing poultry industry. Migratory birds play very important role in the dissemination of antimicrobial resistant pathogen during their fly way specially to poultry farms. Therefore, 750 samples from migratory birds and 300 samples from broiler chicken farms and its environment were collected during the winter seasons of five years (2019 to 2023). The samples were subjected to the isolation of Salmonella enterica and Escherichia coli with the detection of antimicrobial resistance (phenotypic and genotypic) with insight to the genetic similarity between the isolates from migratory birds and broiler chickens' farms. Different members of Enterobacteriaceae were isolated; Salmonella enterica, Escherichia coli, Citrobacter, Enterobacter, Klebsiella, Proteus, Providencia, Serratia, Hafnia. 298 (28.4%) of S. enterica strains belonging to 27 serovars. S. Typhimurium, S. Kentucky, S. Enteritidis and S. Shangani were the common 4 serotypes between migratory birds and farms. Meanwhile, we found 489 (46.6%) isolates of E. coli belonging to 24 serogroups and O91, O128, O26, O125, O55, O103 and O159 were the common 7serogroups between migratory birds and farms samples. The majority of Salmonella (91.6%; 274 out of 298) and E. coli (92%; 450 out of 489) were MDR. The MDRI range of Salmonella and E. coli was 0.08- 1.The genetic similarity between the isolates of migratory birds and broiler chicken farms were detected by ERICPCR and hot map. This study suggests the continuous applications of surveillance programs for migratory birds and biosecurity measures in poultry farms. [ABSTRACT FROM AUTHOR]

Cases of H5 highly pathogenic avian influenzas (HPAI) are on the rise. Although mammalian spillover events are rare, H5N1 viruses have an estimated mortality rate in humans of 60%. No human cases of H5 infection have been reported in Malaysian Borneo, but HPAI has circulated in poultry and migratory avian species transiting through the region. Recent deforestation in coastal habitats in Malaysian Borneo may increase the proximity between humans and migratory birds. We hypothesise that higher rates of human-animal contact, caused by this habitat destruction, will increase the likelihood of potential zoonotic spillover events. In 2015, an environmentally stratified cross-sectional survey was conducted collecting geolocated questionnaire data in 10,100 individuals. A serological survey of these individuals reveals evidence of H5 neutralisation that persisted following depletion of seasonal H1/H3 HA binding antibodies from the plasma. The presence of these antibodies suggests that some individuals living near migratory sites may have been exposed to H5 HA. There is a spatial and environmental overlap between individuals displaying high H5 HA binding and the distribution of migratory birds. We have developed a novel surveillance approach including both spatial and serological data to detect potential spillover events, highlighting the urgent need to study cross-species pathogen transmission in migratory zones. Spillover of avian influenza H5N1 from birds to mammals have been increasingly detected, but reports of cases in humans remain limited. Here, the authors find serological evidence of human exposure to influenza H5N1 in Malaysian Borneo, an important stopover site for migratory shorebirds. [ABSTRACT FROM AUTHOR]

Background: Ecological barriers can shape the movement strategies of migratory animals that navigate around or across them, creating migratory divides. Wind plays a large role in facilitating aerial migrations and can temporally or spatially change the challenge posed by an ecological barrier, with beneficial winds potentially converting a barrier into a corridor. Here, we explore the role wind plays in shaping initial southbound migration strategy among individuals breeding at two sites along an ecological barrier. Methods: Using GPS satellite transmitters, we tracked the southbound migrations of Short-billed Dowitchers (Limnodromus griseus caurinus) from two breeding sites in Alaska to nonbreeding sites in coastal Mexico. The breeding sites were positioned in distinct regions along an ecological barrier – the Gulf of Alaska. We investigated potential differences in migratory timing, wind availability, and tailwind support en route across the Gulf of Alaska between individuals breeding at the two sites. Results: Route choice and arrival timing to wintering sites differed markedly between the two breeding sites: individuals departing from the more westerly site left at the same time as those from further east but crossed the Gulf of Alaska farther west and arrived along the Pacific coast of Mexico an average of 19 days earlier than their counterparts. Dowitchers from both sites departed with slight tailwinds, but once aloft over the Gulf of Alaska, birds from the more westerly site had up to twelve times more tailwind assistance than birds from the more easterly one. Conclusions: The distinct migration strategies and degree of wind assistance experienced by birds at these two breeding sites demonstrates how differences in wind availability along migratory routes can form the basis for intraspecific variation in migration strategies with potential carryover effects. Future changes in wind regimes may therefore interact with changes in habitat availability to influence migration patterns and migratory bird conservation. [ABSTRACT FROM AUTHOR]

Movement is a key means by which animals cope with variable environments. As they move, animals construct individual niches composed of the environmental conditions they experience. Niche axes may vary over time and covary with one another as animals make tradeoffs between competing needs. Seasonal migration is expected to produce substantial niche variation as animals move to keep pace with major life history phases and fluctuations in environmental conditions. Here, we apply a time-ordered principal component analysis to examine dynamic niche variance and covariance across the annual cycle for four species of migratory crane: common crane (Grus grus, n = 20), demoiselle crane (Anthropoides virgo, n = 66), black-necked crane (Grus nigricollis, n = 9), and white-naped crane (Grus vipio, n = 9). We consider four key niche components known to be important to aspects of crane natural history: enhanced vegetation index (resources availability), temperature (thermoregulation), crop proportion (preferred foraging habitat), and proximity to water (predator avoidance). All species showed a primary seasonal niche "rhythm" that dominated variance in niche components across the annual cycle. Secondary rhythms were linked to major species-specific life history phases (migration, breeding, and nonbreeding) as well as seasonal environmental patterns. Furthermore, we found that cranes' experiences of the environment emerge from time-dynamic tradeoffs among niche components. We suggest that our approach to estimating the environmental niche as a multidimensional and time-dynamical system of tradeoffs improves mechanistic understanding of organism-environment interactions. [ABSTRACT FROM AUTHOR]

The current highly pathogenic avian influenza H5N1 panzootic is having substantial impacts on wild birds and marine mammals. Following major and widespread outbreaks in South America, an incursion to Antarctica occurred late in the austral summer of 2023/2024 and was confined to the region of the Antarctic Peninsula. To infer potential underlying processes, we compiled H5N1 surveillance data from Antarctica and sub‐Antarctic Islands prior to the first confirmed cases. [ABSTRACT FROM AUTHOR]

While mangrove ecosystems are rich in biodiversity, they are increasingly impacted by climate change and urban pollutants. The current study provides first insights into the emergence of potentially pathogenic yeasts in Hong Kong's mangroves. Sediment and water samples were collected from ten urban and rural mangroves sites. Initial CHROMagarTM Candida Plus screening, representing the first application of this differential medium for water and soil samples collected from a non-clinical environment, enabled the rapid, preliminary phenotypic identification of yeast isolates from mangroves. Subsequent molecular profiling (ITS and/or 28S nrDNA sequencing) and antifungal drug susceptibility tests were conducted to further elucidate yeast diversity and drug resistance. A diversity of yeasts, including 45 isolates of 18 distinct species across 13 genera/clades, was isolated from sediments and waters from Hong Kong mangroves. Molecular profiling revealed a dominance of the Candida/Lodderomyces clade (44.4%), a group of notorious opportunistic pathogens. The findings also reveal a rich biodiversity of non-Candida/Lodderomyces yeasts in mangroves, including the first reported presence of Apiotrichum domesticum and Crinitomyces flavificans. A potentially novel Yamadazyma species was also discovered. Remarkably, 14.3% of the ubiquitous Candida parapsilosis isolates displayed resistance to multiple antifungal drugs, suggesting that mangroves may be reservoirs of multi-drug resistance. Wildlife, especially migratory birds, may disseminate these hidden threats. With significant knowledge gaps regarding the environmental origins, drug resistance, and public health impacts of pathogenic yeasts, urgent surveillance is needed from a One Health perspective. This study provides an early warning that unrestrained urbanization can unleash resistant pathogens from coastal ecosystems globally. It underscores the necessity for enhanced surveillance studies and interdisciplinary collaboration between clinicians, ornithologists, and environmental microbiologists to effectively monitor and manage this environmental health risk, ensuring the maintenance of 'One Health'. [ABSTRACT FROM AUTHOR]

Since the discovery of viruses, humans have always faced a great challenge in dealing with their subsequent diseases. Coronaviruses have created huge challenges in the world. Coronaviruses are RNA genome viruses from the Coronaviridae family that can cause different diseases in both poultry and humans, but no evidence has been provided for their zoonotic potential, which may be due to the different genera of the viruses that cause diseases in these hosts. There are different ways of transmission for the coronaviruses with airborne being the most common and important route. However, the role of migratory birds in their spread has been recently noticed. Due to the novelty and importance of this issue, we decided to conduct a review study on the role of migratory birds in the spread of coronaviruses. The results show that due to the high possibility of the virus mutations in the host's body, the interspecies barrier can be broken and we can see the direct transmission of the coronaviruses from birds to humans. However, due to the novelty of this topic, more studies are required to acquire a comprehensive knowledge on this matter. [ABSTRACT FROM AUTHOR]

Half of all migratory bird species have declined over the past 30 years, with intercontinental migrants declining faster than their short‐distance migratory counterparts. One potential cause of these declines is habitat loss and degradation on tropical wintering grounds, where agricultural conversion of natural habitats and intensification of traditional, low‐intensity agricultural systems are frequently occurring. Although the broad patterns of wintering migrant abundance are well understood along most flyways, how species' habitat associations vary across disturbance gradients in agricultural landscapes remains a key question, with implications for landscape‐level farm management and restoration activities. We used 328 point count locations and associated habitat assessments targeted at a cohort of eight severely declining Afro‐Palaearctic migratory passerines in the Guineo–Congolian transition zone of Western Africa to model the probability of the presence of migrants within grass, shrub, forb and forest‐covered areas. We found support for the widespread use of early successional habitats retained within traditionally managed farmland by migrants. Most species utilize scrubland on fallows within the agricultural mosaic, especially Spotted Flycatcher, Garden Warbler, Melodious Warbler, Whinchat and Common Nightingale. Only Pied Flycatcher relied upon mature forested areas. The avoidance of mature forested habitats by most species suggests that habitat requirements of severely declining migrant birds must be explicitly considered within conservation and restoration schemes, via mechanisms to retain low‐intensity farming, especially short‐term abandoned fallows that regenerate scrubby areas within the agricultural matrix. Any habitat management within the agricultural matrix should be considered in the context of the needs of local communities. [ABSTRACT FROM AUTHOR]

Population dynamic and eco‐evolutionary responses to environmental variation and change fundamentally depend on combinations of within‐ and among‐cohort variation in the phenotypic expression of key life‐history traits, and on corresponding variation in selection on those traits. Specifically, in partially migratory populations, spatio‐seasonal dynamics depend on the degree of adaptive phenotypic expression of seasonal migration versus residence, where more individuals migrate when selection favours migration.Opportunity for adaptive (or, conversely, maladaptive) expression could be particularly substantial in early life, through the initial development of migration versus residence. However, within‐ and among‐cohort dynamics of early‐life migration, and of associated survival selection, have not been quantified in any system, preventing any inference on adaptive early‐life expression. Such analyses have been precluded because data on seasonal movements and survival of sufficient young individuals, across multiple cohorts, have not been collected.We undertook extensive year‐round field resightings of 9359 colour‐ringed juvenile European shags Gulosus aristotelis from 11 successive cohorts in a partially migratory population. We fitted Bayesian multi‐state capture‐mark‐recapture models to quantify early‐life variation in migration versus residence and associated survival across short temporal occasions through each cohort's first year from fledging, thereby quantifying the degree of adaptive phenotypic expression of migration within and across years.All cohorts were substantially partially migratory, but the degree and timing of migration varied considerably within and among cohorts. Episodes of strong survival selection on migration versus residence occurred both on short timeframes within years, and cumulatively across entire first years, generating instances of instantaneous and cumulative net selection that would be obscured at coarser temporal resolutions. Further, the magnitude and direction of selection varied among years, generating strong fluctuating survival selection on early‐life migration across cohorts, as rarely evidenced in nature. Yet, the degree of migration did not strongly covary with the direction of selection, indicating limited early‐life adaptive phenotypic expression.These results reveal how dynamic early‐life expression of and selection on a key life‐history trait, seasonal migration, can emerge across seasonal, annual, and multi‐year timeframes, yet be substantially decoupled. This restricts the potential for adaptive phenotypic, microevolutionary, and population dynamic responses to changing seasonal environments. [ABSTRACT FROM AUTHOR]

[Display omitted] • European Acrocephalidae show greater prevalence and variety of blood parasites compared with Emberiza schoeniclus. • Migrating birds exhibit variations in blood parasite prevalence and biodiversity depending on their migration routes. • Long-distance migrants of the genus Locustella displayed no infection by either blood parasite, indicating resistance. • The age of migratory birds serves as a key factor in delineating parasite transmission areas effectively. • Transmission areas were either limited to Europe or Africa, or transmission occurred in both regions. During their journeys, migratory birds encounter a wider range of parasites than residents, transporting them over vast distances. While some parasites are widely distributed, transmission is not inevitable and depends on the presence of competent arthropod vectors as well as parasite compatibility with native bird species. Distinguishing between parasite distribution and transmission areas is crucial for monitoring and assessing risks to native bird species, as distribution areas, with the appropriate conditions, could become potential transmission areas. In this study, blood samples from 455 reed-living birds of the genera Acrocephalus , Locustella , and Emberiza, collected in the nature reserve "Die Reit" in Hamburg, Germany were screened, targeting haemosporidian parasites, trypanosomes, and filarioid nematodes. Determination of migratory bird age was employed to ascertain the transmission area of the detected parasites. Transmission areas were determined, based on information provided by resident and juvenile birds as well as findings in competent vectors. Long-distance migratory birds of the genus Acrocephalus showed a higher prevalence and diversity of blood parasites compared with partially migratory birds such as Emberiza schoeniclus. Notably, an age-dependent difference in parasite prevalence was observed in Acrocephalus spp., but not in E. schoeniclus. Nematodes were absent in all examined bird species. Proposed transmission areas were identified for nine haemosporidian lineages, showing three different types of transmission area, either with limited transmission in Europe or Africa, or active transmission in both regions. [ABSTRACT FROM AUTHOR]

Proteus mirabilis, a gram‐negative bacterium, poses a significant public health threat due to its multidrug‐resistant (MDR) characteristics. Here, for the first time, we report the isolation and comprehensive genome analysis of an MDR strain, P. mirabilis KUST‐1312, obtained from migratory birds in Yunnan Province, China. A total of 65 samples, including migratory bird feces, soil, and water from Dianchi Lake, were collected. Standard microbiological techniques were employed to isolate the P. mirabilis KUST‐1312 strain from these samples. Genomic sequencing was conducted using a hybrid assembly strategy, combining Illumina and Oxford nanopore sequencing technologies. Phenotypic testing revealed the MDR nature of P. mirabilis KUST‐1312, displaying resistance to various antibiotics except gentamicin and Cefotaxime. Notably, 15 antimicrobial resistance genes (ARGs), including aph(3′)‐Ia, cat, tet(J), bleO, dfrA12, aadA2, AAC(3)‐IId, bla-TEM-1B, erm(42),aph(6)‐Id, blaPER-1, sul2, aph(3′')‐Ib(2copies), and aph(3′)‐VIb, were identified on a single chromosome. These 15 ARGs were dispersed along three MDR regions, and the boundaries of these regions were consistently flanked by copies of insertion sequences and also contained other genetic elements. Phylogenetic analysis revealed the close relation of P. mirabilis KUST‐1312 with environmental and clinical isolates reported from other continents rather than with Asian isolates. In conclusion, this study reports the first‐ever isolation of an MDR P. mirabilis KUST‐1312 strain from migratory birds globally, particularly in China. There is a need to explore further its prevalence in detail in various ecological niches, including migratory birds. [ABSTRACT FROM AUTHOR]

Background: Avian malaria is caused by diverse parasite species of the genus Plasmodium, and it affects various bird species. The occurrence of this disease in some wild bird species is sparsely documented due to the scarce availability of samples. Hence the pathogenicity in some hosts is not completely known. In addition, feral birds may act as reservoirs bridging the transmission cycle from wild migratory birds to domestic and zoo-kept bird species. Case presentation: An owner of pigeons adopted a feral pigeon (Columba livia forma domestica) and housed it together with his other pet-pigeons. The bird died unexpectedly a few weeks after a surgical procedure and necropsy revealed a severely anaemic carcass, with pale organs and hydropericardium. Histopathologic analysis revealed inflammatory infiltrates in the lung and liver, and monocytes and Kupffer cells contained haemozoin pigment indicative of phagocytosis of Plasmodium-infected erythrocytes. A high erythrocytic infection rate of 18% was evident in tissues and blood vessels in various organs. Furthermore, the thyroid had masses classified as thyroid carcinomas. Immunohistochemistry with anti- Plasmodium falciparum HSP70 antibody revealed positive signals in erythrocytes and intravascular leucocytes. Further microscopy analysis using a Hemacolor-stained impression smear revealed a high parasitaemia with an asynchronous infection showing all erythrocytic stages. Molecular diagnosis by PCR identified Plasmodium relictum, lineage GRW11 as the aetiological agent. The bird presented died most likely due to an acute infection as evidenced by the high blood parasitaemia, leading to major erythrocyte destruction. Further analyses of feral pigeons (n = 22) did not reveal any additional cases of Plasmodium infections. Conclusion: This study reports the first mortality associated with P. relictum lineage GRW11. The study supports previous studies, suggesting that Plasmodium infections are not frequent in pigeons. Host conditions like immunosuppression due to the tumour may have influenced the infection outcome in this fatal case. Use of anti-P. falciparum HSP70 antibody for detection of P. relictum antigens for immune assays in blood and tissue samples will be a useful tool for future studies. [ABSTRACT FROM AUTHOR]

In July 2022, an outbreak of highly pathogenic avian influenza A(H5N1) virus clade 2.3.4.4b occurred among migratory birds at Qinghai Lake in China. The virus circulated in June, and reassortants emerged after its introduction into the area. Surveillance in 2023 showed that the virus did not establish a stable presence in wild waterfowl. [ABSTRACT FROM AUTHOR]

Climate change is a key driver of biodiversity loss in multiple ecosystems, which can act at multiple stages of a species life- and annual cycle. Identifying where, when, and how these impacts may happen is key to understanding, and planning for, the population-level effects of climate change. This study assesses how climate change will impact the breeding and non-breeding areas of the European Bee-eater Merops apiaster, a long-distance migratory bird, by combining correlative species distribution models with recent tracking data to account for population connectivity between breeding and non-breeding sites. The three populations studied (Iberian, German, and Bulgarian) demonstrated different levels of exposure to climate change, as well as different patterns of connectivity. The Iberian breeding population showed high exposure to climate change in both its breeding and non-breeding sites, which may result in significant, interacting impacts on this population. In contrast, breeding populations in Germany are likely to benefit from climate change, both in their breeding and non-breeding range. Connectivity also varied; while most populations demonstrated extremely high connectivity between breeding and non-breeding sites, the Iberian population was substantially more behaviourally flexible, indicating there may be some adaptive capacity of this population to change non-breeding sites if some become less suitable due to climate change. Incorporating breeding and non-breeding areas into species distribution modelling highlights how the impacts of climate change may combine into multiplicative impacts across a species' annual cycle, and how combining methodologies and data sources can provide greater insight into the impact of climate change on migratory species and, in turn, inform conservation action. [ABSTRACT FROM AUTHOR]

Sexing bird species with monomorphic plumage is generally challenging, and sexual size dimorphism (SSD) is often used to develop morphometric-based sexing tools, e.g., using discriminant functions. Within species, local selection pressures, age-related and season-related growth may, however, induce geographical and temporal variations in body size and SSD. Such variations may complicate the development of reliable morphometric-based sexing methods at a broad scale. We first investigated body size variations in a migratory shorebird species with wide breeding and wintering ranges, the Sanderling Calidris alba, within the two breeding populations (Greenland and Russia) and three staging/wintering populations (United Kingdom, Iceland and Mauritania), which belong to the same flyway. Then, for samples from each region, we tested whether site-specific (i.e., "regional") functions performed better than functions developed for birds from the other sites (i.e., "foreign" functions) or than an overall ("flyway") function that combined all sampled individuals. We found minor variations in SSD between regions, but significant differences in body size between sexes and regions. Females were larger than males and, for instance, breeders had longer wings than staging and wintering birds. Regional functions had similar sexing efficiency as any other functions applied to sample from each region, except for Western Africa where the regional function performed slightly better than some of the other functions. Furthermore, the flyway function developed after merging all subsamples had a similar efficiency than the regional functions, i.e., from 75.4% to 90% of correct sex assignment depending on the region. Given the small or lack of benefit in using regional functions, we conclude that the flyway function can be used reliably to sex Sanderlings measured at different sites, years or seasons within the East Atlantic flyway. Our results may help to develop global sexing function for other bird species. [ABSTRACT FROM AUTHOR]

The present study aims to provide a comprehensive bird checklist of Graphic Era (Deemed to be University), Dehradun, India. The study was conducted in from April 2020–March 2022. A total of 85 bird species belonging to 43 families were observed during the study period. The most abundant families were Motacillidae with Six species, followed by Cisticolidae, Columbidae, Muscicapidae, Sturnidae with five species each. Out of total 73 residents and 10 winters migratory and 2 summer migratory species were identified. The percentage of resident, winter visitor and Summer Migratory avian species was found to be 85.58, 11.76 and 2.35% respectively. The Analysis of RDi (relative diversity) results indicated that the family Motacillidae was the most diverse family, with the highest RDi value of 7.1. Total three avian species namely Red-vented bulbul (Pycnonotus cafer) and Rock Pigeons (Columba livia) and Rose-ringed parakeet (Psittacula krameri) were dominantly spared in the University Campus. One species Alexandrine Parakeet (Psittacula eupatria) which observed during the study falls under the Near Threatened (NT) category. The results of the study reflect the importance of such areas as important bird habitats where various local and migratory birds are found to rest and feed. [ABSTRACT FROM AUTHOR]

H5 subtype high-pathogenicity avian influenza (HPAI) viruses continue to devastate the poultry industry and threaten food security and public health. The first outbreak of H5 HPAI in the Philippines was reported in 2017. Since then, H5 HPAI outbreaks have been reported in 2020, 2022, and 2023. Here, we report the first publicly available complete whole-genome sequence of an H5N1 high-pathogenicity avian influenza virus from a case in Central Luzon. Samples were collected from a flock of layer chickens exhibiting signs of lethargy, droopy wings, and ecchymotic hemorrhages in trachea with excessive mucus exudates. A high mortality rate of 96–100% was observed within the week. Days prior to the high mortality event, migratory birds were observed around the chicken farm. Lungs, spleen, cloacal swabs, and oropharyngeal–tracheal swabs were taken from two chickens from this flock. These samples were positive in quantitative RT-PCR assays for influenza matrix and H5 hemagglutinin (HA) genes. To further characterize the virus, the same samples were subjected to whole-virus-genome amplification and sequencing using the Oxford Nanopore method with mean coverages of 19,190 and 2984, respectively. A phylogenetic analysis of the HA genes revealed that the H5N1 HPAI virus from Central Luzon belongs to the Goose/Guangdong lineage clade 2.3.4.4b viruses. Other segments also have high sequence identity and the same genetic lineages as other clade 2.3.4.4b viruses from Asia. Collectively, these data indicate that wild migratory birds are the likely source of H5N1 viruses from the 2022 outbreaks in the Philippines. Thus, biosecurity practices and surveillance for HPAI viruses in both domestic and wild birds should be increased to prevent and mitigate HPAI outbreaks. [ABSTRACT FROM AUTHOR]

Avian influenza viruses (AIV) are a highly contagious disease with economic and public health impact that belongs to the Orthomyxoviridae family. Wild migratory waterbirds are known as the main reservoirs of AVI which can distribute viruses to poultry and humans. Considering that Neor Lake, located in the southeast of Ardabil, is the habitat of migratory waterbirds from the countries around the region, there is a risk of transmission and distribution of influenza viruses from wild migratory birds. The present study aimed to monitor the seroprevalence of AI virus H5, H7, and H9 subtypes in migratory waterbirds of Neor Lake, Ardabil, northwest of Iran. A total of 101 blood samples were randomly collected from seven migratory bird species. HI, test was carried out on sera based on OIE protocol to detect H5, H7, and H9 subtypes. In this study, H5N2 and H7N1 antigens were used for the detection H5 and H7 subtypes, respectively. Suspicious samples on the first test were re-examined with H5N1 and H7N7 antigens. H9N2 antigen was used for the detection H9. Results of the tests performed on sera were negative for H5N1, H5N2, H7N1 and H7N7 viruses. Overall, 11.89 % of birds were seropositive for the H9N2 virus. The highest seroprevalence of the H9N2 virus was in Mallard (25 %) and the lowest seroprevalence was in Whooper swan (10.5 %). In this survey, despite seronegative evidence against H5 and H7 of subtypes, because of the prevalence of high pathogenic avian influenza (HPAI) viruses in countries of the region and some areas of Iran, it is recommended to periodically implement surveillance and control programs such as monitoring of circulating AIV in migratory waterbirds of Neor Lake. [ABSTRACT FROM AUTHOR]

Recently, there has been increased focus on the origins and history of common names for organisms, especially birds. Of particular interest are eponymous common names that reflect our colonial past. While identification of alternative names can be straightforward for some species, for those that migrate across jurisdictions including the lands of multiple Traditional Owner/Indigenous groups, reaching consensus on a single name that reflects the features of the species and their cultural importance can be substantially more complex. Using the migratory Ardenna carneipes as a case study, we propose a new common name (Sable Shearwater) for the species and discuss the many challenges that others will need to consider when navigating this important yet sensitive space. [ABSTRACT FROM AUTHOR]

Assessing habitat quality is critical for migrating birds, with implications for fuel loading, predation risk and timing of departure. To efficiently distribute within stopover sites, migrants rely on various cues that facilitate habitat quality assessment. In this study, we conducted a playback experiment at a mid‐route stopover site to test the effects of vocal cues, specifically bird songs, on habitat redistribution during spring migration. To estimate the effect of bird songs on bird abundance we mist‐netted and ringed birds for 60 days on alternating playback treatment (playing songs of three sylviid warbler species) and no playback (control) days. A nearby site was used to control for fluctuations caused by migration waves. Overall, total bird abundance was significantly increased by the playback treatment. This increase resulted from the attraction of conspecifics (species whose songs were played) rather than of other species – sylviids or others. Correspondingly, species richness was seemingly unaffected. To investigate the relationship between internal‐state factors and the attraction to playback in the most abundantly attracted species, Eurasian Blackcap Sylvia atricapilla, we tested associations with age, sex and body condition index but found no significant effects, possibly because of the limited sample size. Our findings challenge established ideas regarding heterospecific attraction and contradict previous studies. Attraction to bird song is discussed in the context of geographical location, timing and internal drivers. Vocal cues, specifically bird songs, may affect micro‐habitat selection by migrating songbirds during stopovers. Consequently, we call for consideration of the influence of the acoustic environment on birds during migratory stopover in future studies, habitat management and conservation efforts. [ABSTRACT FROM AUTHOR]

Migratory waterfowl are a harvested resource shared among multiple European countries, exposing them to potential overexploitation. Management of take is challenging since the life cycle of migratory waterfowl consists of several stages distributed among several locations, with possible spatio-temporal overlap among populations with differing population trends. Successful harvest management in such situations requires knowledge about the connections between breeding and non-breeding locations, and where birds are harvested. Breeding populations of Eurasian wigeon (Mareca penelope) are declining in Finland, underlining the need for more effective harvest management. Relative proportions and temporal distribution of local breeding birds and migrants from a larger Russian breeding population within the Finnish hunting bag has been unknown to date. We studied spatio-temporal origins of Finnish harvested wigeon by measuring stable-hydrogen (δ2H) isotope values from legally harvested birds. We modelled the changes in δ2H values of the feather samples within the hunting season using Gaussian processes and found that the origin of harvested wigeon in Finland changed during the hunting season and differed by age and sex. In juveniles and adult females but not in adult males, origin of harvested birds shifted from local and possibly western Russian birds to more long-distance migratory birds during the harvest season. These patterns likely reflected sex- and age-specific differences in migratory behaviour of Eurasian wigeon in the East Atlantic flyway, which can be used to guide future management and conservation of this species through the implementation of spatio-temporal harvest regulation. [ABSTRACT FROM AUTHOR]

Migration is one of the most extreme and energy demanding life history strategies to have evolved in the animal kingdom. In birds, champions of long-distance migrations, the seasonal emergence of the migratory phenotype is characterised by rapid physiological and metabolic remodelling, including substantial accumulation of fat stores and increases in nocturnality. The molecular underpinnings and brain adaptations to seasonal migrations remain poorly understood. Here, we exposed Common quails (Coturnix coturnix) to controlled changes in day length to simulate southward autumn migration, and then blocked the photoperiod until birds entered the non-migratory wintering phase. We first performed de novo RNA-Sequencing from selected brain samples (hypothalamus) collected from birds at a standardised time at night, either in a migratory state (when restlessness was highest and at their body mass peak), or in a non-migratory state and conducted differential gene expression and functional pathways analyses. We found that the migratory state was associated with up-regulation of a few, yet functionally well defined, gene expression networks implicated in fat trafficking, protein and carbohydrate metabolism. Further analyses that focused on candidate genes (apolipoprotein H or APOH, lysosomal associated membrane protein-2 or LAMP2) from samples collected during the day or night across the entire study population suggested differences in the expression of these genes depending on the time of the day with the largest expression levels being found in the migratory birds sampled at night. We also found that expression of APOH was positively associated with levels of nocturnal activity in the migratory birds; such an association was absent within the non-migratory birds. Our results provide novel experimental evidence revealing that hypothalamic changes in expression of apolipoprotein pathways, which regulate the circulatory transport of lipids, are likely key regulatory activators of nocturnal migratory movements. Our study paves the way for performing deeper functional investigations on seasonal molecular remodelling underlying the development of the migratory phenotype. [ABSTRACT FROM AUTHOR]

Human activities are forcing wildlife to confront selective pressures different from those under which they evolved. In seasonal environments, migration evolved as an adaptation to fluctuating resource availability. Anthropogenic subsidies modify resource dynamics by providing a steady food source that is not subject to seasonality. Globally, many migratory populations are becoming increasingly resident in response to food supplementation. While these population-level shifts are assumed to arise from changing fitness consequences of individual behaviour in response to resource dynamics, these mechanisms are often difficult to quantify and disentangle. Here, we quantified fitness consequences of responses to anthropogenic subsidies in partially migratory wood storks (Mycteria americana) in the heavily urbanized southeastern United States. First, we tested whether individual migratory behaviour is linked to different responses to anthropogenic subsidies. Second, we quantified fitness consequences of these behavioural responses. We found that, in our system, migration and residency are alternative behavioural tactics associated with different responses to food supplementation. In turn, the use of anthropogenic resources alters a fitness component by enhancing nest survival. These results provide a mechanistic examination of how animals may respond to human-modified resource dynamics and how fitness consequences of individual tactics may translate into behavioural shifts at the population level. [ABSTRACT FROM AUTHOR]

ABSTRACT Our study represents the first attempts to describe the ultrastructure features in addition to SEM‐EDX analysis of the pecten oculi of the nocturnal, visually active Eurasian stone‐curlew. The present study was carried out on 10 normal pecten oculi from the migrant Eurasian stone‐curlew (Burhinus oedicnemus) that was captured from the Northern Egyptian coast, Edku Lake, Edku, Behera, Egypt. The intraocular folded quadrilateral fan black pecten oculi was observed on the posteroinferior wall of the eyeball. The pecten oculi had 18–20 pleats, with narrow spaces in‐between. Our SEM findings showed a tortuous, coiled pecteneal surface due to numerous blood capillaries. The apical part was oriented toward the ciliary body, but the basal part was derived from the retina, just behind the optic nerve. The outer pleat surfaces are covered by the vitreopecteneal limiting membrane, which carries numerous hyalocyte cells on the outer pleat surface. The transverse sections revealed numerous blood capillaries surrounded by numerous melanin granules. Each basal part was surrounded by a thin, elevated ridge. Our SEM‐EDX analysis revealed that carbon is the highest (half percent), oxygen represents about one‐third, and nitrogen is one‐fifth percent of all elements. The lowest elements are sulfate at the apical part and phosphorus in the middle and basal parts. In conclusion, our findings reveal that the number of pecteneal pleats is related to the nocturnal active visual pattern and the lifestyle of this migratory bird. [ABSTRACT FROM AUTHOR]

Migratory shorebirds are one of the fastest declining groups of North American avifauna. Yet, relatively little is known about how these species select habitat during migration. We explored the habitat selection of Buff-breasted Sandpipers (Calidris subruficollis) during spring and fall migration through the Texas Coastal Plain, a major stopover region for this species. Using tracking data from 118 birds compiled over 4 years, we found Buff-breasted Sandpipers selected intensively managed crops such as sod and short-stature crop fields, but generally avoided rangeland and areas near trees and shrubs. This work supports prior studies that also indicate the importance of short-stature vegetation for this species. Use of sod and corn varied by season, with birds preferring sod in spring, and avoiding corn when it is tall, but selecting for corn in fall after harvest. This dependence on cropland in the Texas Coastal Plain is contrary to habitat use observed in other parts of their non-breeding range, where rangelands are used extensively. The species' almost complete reliance on a highly specialized crop, sod, at this critical stopover site raises concerns about potential exposure to contaminants as well as questions about whether current management practices are providing suitable conditions for migratory grassland birds. [ABSTRACT FROM AUTHOR]

Until recent events, the Antarctic was the only major geographical region in which high pathogenicity avian influenza virus (HPAIV) had never previously been detected. Here we report on the detection of clade 2.3.4.4b H5N1 HPAIV in the Antarctic and sub-Antarctic regions of South Georgia and the Falkland Islands, respectively. We initially detected H5N1 HPAIV in samples collected from brown skuas at Bird Island, South Georgia on 8th October 2023. Since this detection, mortalities were observed in several avian and mammalian species at multiple sites across South Georgia. Subsequent testing confirmed H5N1 HPAIV across several sampling locations in multiple avian species and two seal species. Simultaneously, we also confirmed H5N1 HPAIV in southern fulmar and black-browed albatross in the Falkland Islands. Genetic assessment of the virus indicates spread from South America, likely through movement of migratory birds. Critically, genetic assessment of sequences from mammalian species demonstrates no increased risk to human populations above that observed in other instances of mammalian infections globally. Here we describe the detection, species impact and genetic composition of the virus and propose both introductory routes and potential long-term impact on avian and mammalian species across the Antarctic region. We also speculate on the threat to specific populations following recent reports in the area. High pathogenicity avian influenza virus has a wide host range and has been detected across a large geographic area. Here, the authors present evidence of spread to the Antarctic and sub-Antarctic regions, with signs of clinical infection and positive virus detection in birds and elephant seals. [ABSTRACT FROM AUTHOR]

Ecologically, the presence of avifauna is a crucial indicator of ecosystem equilibrium. The diversity of bird species and their community structure serves as an essential tool for assessing ecological impacts. This study aimed to evaluate the species composition, evenness, and diversity of wild bird species across different habitats in Egypt from May 2023 to February 2024. The study identified 17,387 individuals from 40 resident bird species belonging to 25 families and 10 orders. The house sparrow exhibited the highest relative abundance among resident bird species, followed by the western cattle egret, barn swallow, house crow, rock pigeon, little egret, hooded crow, laughing dove, and common myna. In terms of migratory birds, 6,050 individuals from 39 species across 22 families and 11 orders were observed. The slender-billed gull, little stint, great cormorant, common ringed plover, the European beeeater, black-winged stilt, and white wagtail had the highest relative abundances among migratory species. The distribution of bird species across different sites revealed that the coastal area (CA) and the Suez Canal & Gulf Suez (SCGS) each harbored 25% of the total number of resident species, followed by the Nile Delta (ND) with 21%, the Nile Valley (NV) with 16%, and the Faiyum (F) area with 13%. For migratory birds, the CA accounted for 48% of all migratory species, followed by the F area at 23%, ND at 13%, SCGS at 11%, and NV at 5%. The highest species richness was recorded in the CA, followed by SCGS, ND, F, and NV. The highest values for the Shannon and Simpson indices were found in the CA, NV, ND, SCGS, and F areas, respectively. It can be concluded that the Egyptian environment, especially aquatic habitats, is a valuable resource for the Egyptian avifauna by providing food sources and nesting sites. [ABSTRACT FROM AUTHOR]

Simple Summary: There are few data sets in bird migration research that go back more than a century. The Carpathian Basin is one of the exceptions, where spring return data for migratory birds were intensively collected and published between 1894 and 1926. One of the most numerous records was that of the Eurasian Woodcock, which provided an opportunity to study the timing of migration of the species and the influence of different environmental and geographical factors on migration. In years with snowier and colder weather, birds returned later than in years with milder weather. The migration occurred earlier in lowlands than in mountain and hill areas. Food availability played a key role in explaining the differences between years and geographical regions. We also showed a two week difference in arrival time between southwestern and northeastern regions. It is likely that climate change is now causing the species to migrate much earlier, but the extent of this cannot be accurately determined without comparison with recent data. In the present study, 7344 spring observations of a short-distance migratory species, the Eurasian Woodcock, from the Carpathian Basin between 1894 and 1926 were used to investigate the timing of the species' migration and how different environmental factors influenced it. We used a generalized additive model (GAM) to explore migratory patterns by using environmental and geographical variables. In years when the weather was colder and snowier, the birds migrated weeks later than in years with milder weather. This may be due to the availability of earthworms, which are the most important food for the species. In areas at lower altitudes, migration occurred earlier than in mountainous areas, which may also be due to the different weather. Furthermore, a two week difference was observed between the south-western and north-eastern parts of the Carpathian Basin. This difference is still present nowadays, but the timing of migration has shifted earlier than in the past, probably due to climate change. It would also be important to compare the historical data with recent data to gain a better understanding of the effects of climate change on the migration of the Eurasian Woodcock. [ABSTRACT FROM AUTHOR]

Simple Summary: The study focused on the comparison of culturable yeast communities in the feces of two populations of Mew Gulls depending on the breeding site: natural and urban. It was found that the species diversity of yeasts in the feces of gulls from the natural population was significantly higher, while the diversity of pathogenic species in the feces of birds from the anthropogenic population increased. The proportion of strains of pathogens (Candida, Rhodotorula) isolated from the feces of the anthropogenic colony that were resistant to conventional antibiotics was high. Indeed, populations of migratory birds breeding in an anthropogenic area could be involved in the global spread of the "alarming" geography of antifungal resistance, which is an urgent public health problem. Migratory birds play an important role in the spread of yeasts in the environment over long distances and in different geographical regions. Human activities, in turn, have a major impact on the biology of wild birds and, consequently, on the microbial communities for which birds act as carriers and disseminators. We sought to assess the "response" of the diversity of culturable yeasts in the feces of Mew Gulls to the type of nesting site (natural/anthropogenic) during the breeding season from April to October 2023. We isolated and molecularly identified 26 yeast species. The species composition in the feces of birds from the natural habitat was more diverse, and the diversity increased from April to October. In contrast, the diversity in the feces of birds from the urban habitat decreased from April to October. Analysis of susceptibility to conventional antibiotics (fluconazole, voriconazole, and amphotericin B) using the CLSI BMD (Clinical and Laboratory Standards Institute broth microdilution) method in isolated strains of opportunistic Candida (C. parapsilosis and C. tropicalis) and strains of the emerging pathogen Rhodotorula mucilaginosa showed that the proportion of resistant strains was higher in strains isolated from the feces of birds from the anthropogenic population. Mew Gulls that spent their breeding season near a landfill and flew away for wintering appear to be a source for the spread of pathogenic yeasts with resistance against antifungal agents. [ABSTRACT FROM AUTHOR]

As industrial informatization progresses, virtual simulation technologies are increasingly demonstrating their potential in industrial applications. These systems utilize various sensors to capture real-time factory data, which are then transmitted to servers via communication interfaces to construct corresponding digital models. This integration facilitates tasks such as monitoring and prediction, enabling more accurate and convenient production scheduling and forecasting. This is particularly significant for flexible or mixed-flow production modes. Bionic optimization algorithms have demonstrated strong performance in factory scheduling and operations. Centered around these algorithms, researchers have explored various strategies to enhance efficiency and optimize processes within manufacturing environments.This study introduces an efficient migratory bird optimization algorithm designed to address production scheduling challenges in an assembly shop with mold quantity constraints. The research aims to minimize the maximum completion time in a batch flow mixed assembly flow shop scheduling problem, incorporating variable batch partitioning strategies. A tailored virtual simulation framework supports this objective. The algorithm employs a two-stage encoding mechanism for batch partitioning and sequencing, adapted to the unique constraints of each production stage. To enhance the search performance of the neighborhood structure, the study identifies and analyzes optimization strategies for batch partitioning and sequencing, and incorporates an adaptive neighborhood structure adjustment strategy. A competition mechanism is also designed to enhance the algorithm's optimization efficiency. Simulation experiments of varying scales demonstrate the effectiveness of the variable batch partitioning strategy, showing a 5–6% improvement over equal batch strategies. Results across different scales and parameters confirm the robustness of the algorithm. [ABSTRACT FROM AUTHOR]

Changes in leaf phenology from warming spring and autumn temperatures have lengthened the temperate zone growing "green" season and breeding window for migratory birds in North America. However, the fitness benefits of an extended breeding season will depend, in part, on whether species have sufficient dietary flexibility to accommodate seasonal changes in prey availability. We used fecal DNA metabarcoding to test the hypothesis that seasonal changes in the diets of the insectivorous, migratory black‐throated blue warbler (Setophaga caerulescens) track changes in the availability of arthropod prey at the Hubbard Brook Experimental Forest, New Hampshire, USA. We examined changes across the breeding season and along an elevation gradient encompassing a 2‐week difference in green season length. From 98 fecal samples, we identified 395 taxa from 17 arthropod orders; 242 were identified to species, with Cecrita guttivitta (saddled prominent moth), Theridion frondeum (eastern long‐legged cobweaver), and Philodromus rufus (white‐striped running crab spider) occurring at the highest frequency. We found significant differences in diet composition between survey periods and weak differences among elevation zones. Variance in diet composition was highest late in the season, and diet richness and diversity were highest early in the season. Diet composition was associated with changes in prey availability surveyed over the green season. However, several taxa occurred in diets more or less than expected relative to their frequency of occurrence from survey data, suggesting that prey selection or avoidance sometimes accompanies opportunistic foraging. This study demonstrates that black‐throated blue warblers exhibit diet flexibility and track seasonal changes in prey availability, which has implications for migratory bird responses to climate‐induced changes in insect communities with longer green seasons. [ABSTRACT FROM AUTHOR]

Environment and behavior are widely understood to affect bird morphology, which can lead to differences among subspecies or populations within a wide‐ranging species. Several patterns of latitudinal gradients in morphology have been described, though Allen's and Bergmann's rules are the most well‐known and have been tested and confirmed across a diversity of taxa and species. These state that individuals at higher latitudes will have larger bodies (Bergmann's Rule) but smaller extremities (Allen's Rule) to conserve heat in colder climates. Migratory behavior also can influence avian morphology, particularly wing shape, where migratory birds tend to have longer, more pointed wings than residents. The Black Oystercatcher (Haematopus bachmani) is a large, partially migratory shorebird species restricted to intertidal habitats and distributed from Alaska to Baja California, spanning about 35° of latitude. A large proportion of Black Oystercatchers that breed in Alaska are migratory, where nearly all individuals breeding in British Columbia through the southern end of their range remain resident through the annual cycle. Their broad latitudinal range and diversity in migratory behavior may drive geographic variation in morphology. Here we evaluate three explanations for geographic variation in morphology of the Black Oystercatcher using data from seven sites across two regions: Alaska and British Columbia. We found evidence consistent with Allen's but not Bergmann's rule; birds in Alaska have shorter bills than those in British Columbia, and these findings held when controlling for body size using wing length. Despite regional differences in migratory behavior, we detected no difference in the wing shape of birds in Alaska and British Columbia. Differences between sexes and among sites suggest that multiple factors drive patterns of morphological variation in the Black Oystercatcher. [ABSTRACT FROM AUTHOR]

During spring, migratory birds are required to optimally balance energetic costs of migration across heterogeneous landscapes and weather conditions to survive and reproduce successfully. Therefore, an individual's migratory performance may influence reproductive outcomes. Given large‐scale changes in land use, climate, and potential carry‐over effects, understanding how individuals migrate in relation to breeding outcomes is critical to predicting how future scenarios may affect populations. We used GPS tracking devices on 56 Greater White‐fronted Geese (Anser albifrons) during four spring migrations to examine whether migration characteristics influenced breeding propensity and breeding outcome. We found a strong longitudinal difference in arrival to the breeding areas (18 days earlier), pre‐nesting duration (90.9% longer), and incubation initiation dates (9 days earlier) between western‐ and eastern‐Arctic breeding regions, with contrasting effects on breeding outcomes, but no migration characteristic strongly influenced breeding outcome. We found that breeding region influenced whether an individual likely pursued a capital or income breeding strategy. Where individuals fell along the capital‐income breeding continuum was influenced by longitude, revealing geographic effects of life‐history strategy among conspecifics. Factors that govern breeding outcomes likely occur primarily upon arrival to breeding areas or are related to individual quality and previous breeding outcome, and may not be directly tied to migratory decision‐making across broad scales. [ABSTRACT FROM AUTHOR]

Migration timing in long‐distance migratory birds plays an essential role in individual survival and fitness and is thought to be driven by circannual routines cued by photoperiod with some plasticity to environmental conditions. We examined the individual order of migration timing in purple martins (Progne subis), a neotropical migratory songbird that travels between breeding sites throughout eastern North America and nonbreeding sites in Brazil. Migration timing data were collected for 295 different individual purple martins over 9 years using light‐level geolocators deployed at breeding sites across the range. We used linear mixed‐effect models to examine the influence of the rank order of individual departure dates in one season on the rank order of four subsequent migration events while controlling for the effects of breeding latitude, sex, and age. Overall, we found evidence for consistent individual timing that can extend across 8 months and 12,000–24,000 km of migration. Individual rank order of migration timing in purple martins was generally conserved across migrations with consistent timings between fall departure dates from, and spring arrival dates to the breeding site the following year (0.28 ± 0.03, 95% CI 0.22–0.34), as well as at a finer scale across fall migration (0.33 ± 0.05, 95% CI 0.23–0.43), over the stationary nonbreeding period (0.39 ± 0.04, 95% CI 0.31–0.47), and across spring migration (0.03 ± 0.001, 95% CI 0.028–0.032). These results demonstrate that purple martins exhibit consistency in individual migration timing throughout the annual cycle that is likely driven by inherent individual circannual schedules. We additionally found that migration distance played a significant role, as the consistency of individual timing lessened over longer distances. Understanding how individual birds time migrations and if individuals are consistent between events can provide insight into how birds respond to shifts in their environment with climate change. [ABSTRACT FROM AUTHOR]

Worldwide, shorebirds are some of the most endangered migratory species, especially the rufa Red Knot (Calidris canutus). Global change (e.g., human development, habitat loss, climate variability, sea level rise) has a significant impact on Red Knot populations, generating threats throughout their flyway. Since the initial decline of Red Knot populations in the late 1990s, research has been conducted to understand the threats Red Knots face and inform management actions to protect and aid in the recovery of these migratory birds. Shorebird physiology, especially for Red Knots, however, places limitations on attachment methods for long retention of tags. For this reason, we report on the novel use of satellite tags attached to Red Knots in the Atlantic Flyway using a new glue and suture method and describe this new methodology for tag attachment. Our results showed that tags attached with the glue and suture method versus only glue stayed on the bird 142% longer in year 1 and 162–320% longer in year 2 (depending on the tag type), with a tag retention time of up to 5 months. The glue and suture attachment method is a successful tag attachment method for migratory shorebirds, especially for species where other methods cause adverse effects. This method provides long-term retention of the tag without causing negative impacts to migration, survival, or breeding. With advances in transmitter technology, this is the best available method for longer retention time for these satellite tags. [ABSTRACT FROM AUTHOR]

In the last decade, geolocators have been implemented to track birds and have provided insights into the migration patterns of small birds not previously available. These devices have been assumed to have minimal impact on survival, although formal survival analyses are often not conducted when geolocators are used. We deployed geolocators on 29 Cliff Swallows (Petrochelidon pyrrhonota) and compared their survival rates over 2 subsequent seasons to 95 birds caught at the same time and site but that had standard aluminum bands only. We recovered 1 geolocator with usable data. The migratory track for this bird indicated stopover behavior, more rapid movement in spring than in fall, and significant over-water travel during spring migration. We found that birds with geolocators had an annual survival probability of 0.07, compared to 0.60 for birds without geolocators. Although this result should be interpreted with caution due to small sample sizes, it suggests that geolocators may affect survival of small aerial insectivore species. Geolocators provide invaluable information on migratory routes of birds, but the effects of geolocators on survival should be further studied. [ABSTRACT FROM AUTHOR]

Every night during spring and autumn, the mass movement of migratory birds redistributes bird abundances found on the ground during the day. However, the connection between the magnitude of nocturnal migration and the resulting change in diurnal abundance remains poorly quantified. If departures and landings at the same location are balanced throughout the night, we expect high bird turnover but little change in diurnal abundance (stream‐like migration). Alternatively, migrants may move simultaneously in spatial pulses, with well‐separated areas of departure and landing that cause significant changes in the abundance of birds on the ground during the day (wave‐like migration). Here, we apply a flow model to data from weather surveillance radars (WSR) to quantify the daily fluxes of nocturnally migrating birds landing and departing from the ground, characterizing the movement and stopover of birds in a comprehensive synoptic scale framework. We corroborate our results with independent observations of the diurnal abundances of birds on the ground from eBird. Furthermore, we estimate the abundance turnover, defined as the proportion of birds replaced overnight. We find that seasonal bird migration chiefly resembles a stream where bird populations on the ground are continuously replaced by new individuals. Large areas show similar magnitudes of take‐off and landing, coupled with relatively small distances flown by birds each night, resulting in little change in bird densities on the ground. We further show that WSR‐inferred landing and take‐off fluxes predict changes in eBird‐derived abundance turnover rate and turnover in species composition. We find that the daily turnover rate of birds is 13% on average but can reach up to 50% on peak migration nights. Our results highlight that WSR networks can provide real‐time information on rapidly changing bird distributions on the ground. The flow model applied to WSR data can be a valuable tool for real‐time conservation and public engagement focused on migratory birds' daytime stopovers. [ABSTRACT FROM AUTHOR]

The article delves into the confusion with the interpretations and enforcement of the Migratory Bird Treaty Act (MBTA) regarding avian interactions with the built environment, particularly the intentional taking or killing of protected bird species. Topics discussed include sustainable development and voluntary initiatives for the protection of plants and animal species, provisions of the Lacey Act and MBTA on wildlife protection, and building modifications to prevent bird collisions.

Consequences of climatic change in migratory and resident birds in terms of behavior, physiology, genetics, ecology, and evolution are the best documented changes reported in the animal world. This systematic review focuses on the studies conducted/published in the two most recent decades (2001–2020) regarding the effects of global climate change on birds. The PSALSAR [Protocol, Search, Appraisal, Synthesis, Analysis and Reporting results] approach was used to conduct the review. Information from a total of 170 publications in two databases (PUBMED and Google Scholar) including journal articles, books, book chapters, reviews, and reports were extracted and analyzed under ten criteria. An increase in publication number was observed in both databases. Overall, the highest number of publications were available for the year 2019. The highest number (141) of selected publications were journal articles. The highest number of articles (41) were from PLOS One. Selected articles' study periods ranged between 1830 to 2100. Twenty‐eight studies were done in a global scale. Other studies scaled around eight regions, five continents and 40 countries. Behavior and ecology related consequences were studied the most. Eighty‐two studies used primary data sources and 88 studies used secondary data sources. Quantification, mapping, and modeling were the most utilized modes of assessments. Most studies species are Pied Flycatcher (Ficedula hypoleuca), Blue Tit (Cyanistes caeruleus), and Tree Swallow (Tachycineta bicolor). Majority of the publications were based on expansion of knowledge. [ABSTRACT FROM AUTHOR]

Abstract Multidrug resistance (MDR) considered as global crisis facing poultry industry. Migratory birds play very important role in the dissemination of antimicrobial resistant pathogen during their fly way specially to poultry farms. Therefore, 750 samples from migratory birds and 300 samples from broiler chicken farms and its environment were collected during the winter seasons of five years (2019 to 2023). The samples were subjected to the isolation of Salmonella enterica and Escherichia coli with the detection of antimicrobial resistance (phenotypic and genotypic) with insight to the genetic similarity between the isolates from migratory birds and broiler chickens’ farms. Different members of Enterobacteriaceae were isolated; Salmonella enterica, Escherichia coli, Citrobacter, Enterobacter, Klebsiella, Proteus, Providencia, Serratia, Hafnia. 298 (28.4%) of S. enterica strains belonging to 27 serovars. S. Typhimurium, S. Kentucky, S. Enteritidis and S. Shangani were the common 4 serotypes between migratory birds and farms. Meanwhile, we found 489 (46.6%) isolates of E. coli belonging to 24 serogroups and O91, O128, O26, O125, O55, O103 and O159 were the common 7serogroups between migratory birds and farms samples. The majority of Salmonella (91.6%; 274 out of 298) and E. coli (92%; 450 out of 489) were MDR. The MDRI range of Salmonella and E. coli was 0.08- 1.The genetic similarity between the isolates of migratory birds and broiler chicken farms were detected by ERICPCR and hot map. This study suggests the continuous applications of surveillance programs for migratory birds and biosecurity measures in poultry farms.

Abstract The recent Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic highlights the significant threat coronaviruses (CoVs) pose to public health. With their extensive cross-continental movements, migratory birds have the potential to serve as reservoirs and vectors for CoVs. This study aimed to investigate the prevalence of CoVs in birds in densely populated areas of Guangdong Province, China. Of the 128 samples collected from birds, six tested positive for CoVs (4.7%, 95% CI: 1.7–9.9%), and three complete viral genomes were obtained through viral metagenomics and PCR. Phylogenetic analysis revealed that two CoVs (MD_XN18 and SG_DWY40) belonged to the Gammacoronavirus genus, while one (CP_XN11) belonged to the Deltacoronavirus genus. Homology analysis revealed that the MD_XN18 strain discovered in mallards shares 95.6–97.4% sequence similarity with chicken infectious bronchitis viruses (IBVs), providing direct evidence that migratory mallards can transmit avian IBVs. Recombination analysis suggested that two genomic regions of SG_DWY40 could originate from unknown sources through recombination, potentially leading to the expression of a novel viral protein, provisionally named NS3.5. These findings underscore the ongoing transmission and evolution of CoVs among birds in cities near Guangdong Province, emphasizing the need for continued monitoring and research.