Bird banding is internationally recognized as one of the most useful and cost-effective methods for avian monitoring. While widely adopted in Europe and North America—where it has played a pivotal role in collecting foundational data, significantly advancing the understanding of avian demography, migration, population dynamics, and conservation—bird banding in Asia lags considerably behind. Given Asia's rich avian diversity and the severe threats the birds face, there is an urgent need to promote increased bird banding as part of a strategy to effectively conserve both resident and migratory birds and protect their habitats across the region. However, information on the overall status of bird banding in Asia remains scarce, limiting the development of future initiatives in this field. To address this gap, based on integrative methods of banding data analysis, a literature review, and a questionnaire survey across 16 major Asian countries, we delineate the history and status of bird banding across the region, and review how bird banding efforts contributed to the collection of standardized data supporting avian conservation and research. We identify the key challenges facing bird banding in Asia, with a focus on the lack of legislation and policy support, shortage of trained personnel, and incomplete bird banding network. As a response, we indicate the prospects for the future development of Asian bird banding, highlighting priorities of establishing clear and consistent protocols, training and recruiting qualified banders, building and connecting banding networks, and expanding the educational and outreach role of banding stations. We offer new insights into promoting Asian bird banding as an indispensable bird monitoring tool in the challenges of avian conservation at both the flyway and global scales.

Evaluating the habitat suitability of flagship species and its key influencing factors is vital for understanding potential conservation issues and developing coping strategies. We surveyed the wintering population size and distribution of the Black-necked Crane (Grus nigricollis) in the Yarlung Zangbo River Basin (YZRB) from 10 to 29 January 2022, and predicted the current potentially suitable habitat distribution and its effective factors using the MaxEnt model. A total of 9337 wintering Black-necked Cranes were recorded in the YZRB in 2022, 76.58 % of which were primarily found in Lhunzub, Samzhubze, Namling, and Lhaze. Compared to 2018, the crane population has exhibited a notable decline in Samzhubze and Taktse, likely due to farmland plowing, winter irrigation, changes in agricultural practices, road construction and hydraulic projects. The crane population within various counties exhibited a significant positive correlation with the suitable habitat area (r = 0.70, P = 0.002, n = 17). We also found that the currently suitable habitat area covered 17,204 km2, of which only 3244 km2 (18.86 %) was effectively protected at the national level, which was predominantly distributed in farmland and rangeland habitats characterized by gentle slopes, altitudes not exceeding 4500 m, and proximity to human settlements along rivers, where suitable isothermal values (51) and less seasonal precipitation (20 mm) prevail. Our study will be helpful for formulating reasonable conservation strategies to protect the core population of this threatened highland flagship species.

Migratory birds, because of their migration and roosting characteristics, can serve as major vectors for long-distance transmission, recombination, and evolution of adenoviruses. China is one of the countries possessing the widest variety of birds in the world, with the global migration routes covering almost the entire territory. However, avian adenoviruses haven't been systematically studied. In the current study, PCR-based molecular methods were used to characterize the adenoviruses in 38 migratory bird species from nine provinces in China from October 2020 to March 2021. Aviadenoviruses (11.4%, 79/690) were predominantly detected, followed by siadenoviruses (6.2%, 43/690) and barthadenoviruses (1.3%, 9/690). Phylogenetic analysis demonstrated about half of the aviadenoviruses clustered with Duck adenovirus 2, revealing potential association with poultry animals. A high portion (67.2%, 88/131) of the DNA polymerase sequences had <85% identity to any known sequences, indicating the potential presence of novel species, particularly in bar-headed goose where adenoviruses of all three genera were detected for the first time. The clustering of adenovirus sequences from different birds and regions in the same branch of the phylogenetic analysis suggested their close genetic relationships, indicating the transmission of adenoviruses across bird species. Host exchange and recombination events were observed, which might reflect the plasticity of these viruses and the mechanism for the emergence of novel viruses. The prevalence and characteristics of the adenoviruses in migratory birds demonstrated the wide distribution of novel adenovirus species and possible transmission between wild birds and domestic animals.

Migratory birds have been found to carry and spread pathogens, contaminating the environment and causing diseases in humans and other animals. To our knowledge, there hasn’t been any systematic targeted screening for known pathogens in migratory birds. In the current study, customized real time PCR based TaqMan Array Cards (TAC) were used to detect 99 human disease related pathogens and 20 antimicrobial resistance (AMR) genes in migratory birds at 10 habitat sites in China. The results showed that 30.5

Extrinsic and endocrine factors are important mechanisms influencing the timing of spring bird migration. Whooper swans (Cygnus cygnus), including 122 adults and subadults over one year old and 98 juveniles under one year old, were satellite tracked to obtain detailed locational data at a wintering ground from 2015 to 2020. We assessed the effects of temperature, wind, photoperiod, available food resources, and sex hormones on age-related timing of spring migration. Our results suggested that both photoperiod and temperature had the greatest impacts on the timing of spring migration of adults, subadults and juveniles when food resources and wind conditions were favourable. With increasing photoperiod and temperature, the peak sex hormone concentrations of adults and subadults occurred one month earlier than that of juveniles, which corresponded to the peak of their departure time. Our study showed the synergistic impact of photoperiod and temperature and their variation among adults, subadults and juveniles on the initiation of spring migration. Compared with juveniles, adults and subadults with spring migration experience and reproductive needs could adjust their behaviours more quickly before departure based on changes in environmental conditions.

Highly pathogenic avian influenza virus (HPAIV) A H5, particularly clade 2.3.4.4, has caused worldwide outbreaks in domestic poultry, occasional spillover to humans, and increasing deaths of diverse species of wild birds since 2014. Wild bird migration is currently acknowledged as an important ecological process contributing to the global dispersal of HPAIV H5. However, this mechanism has not been quantified using bird movement data from different species, and the timing and location of exposure of different species is unclear. We sought to explore these questions through phylodynamic analyses based on empirical data of bird movement tracking and virus genome sequences of clade 2.3.4.4 and 2.3.2.1. First, we demonstrate that seasonal bird migration can explain salient features of the global dispersal of clade 2.3.4.4. Second, we detect synchrony between the seasonality of bird annual cycle phases and virus lineage movements. We reveal the differing exposed bird orders at geographical origins and destinations of HPAIV H5 clade 2.3.4.4 lineage movements, including relatively under-discussed orders. Our study provides a phylodynamic framework that links the bird movement ecology and genomic epidemiology of avian influenza; it highlights the importance of integrating bird behavior and life history in avian influenza studies.

The Eurasian Goshawk (Accipiter gentilis schvedowi) is widely distributed across Russia and East Asia and is a second-class key protected wild animal species in China. There have been few studies on the migration routes of this species. Here, we present data from solar-powered satellite transmitters we placed on 4 goshawks at Changdao Island, Shangdaong Province, China, to follow them over the period of 2008-2013 and document their migratory routes and site fi delity. We obtained 7 spring and 9 autumn migration trajectories. We identified Shangdong and Anhui in China as wintering sites and Inner Mongolia, China, and Russia as breeding areas of Eurasian Goshawks. The spring migration fl ights covered 1,936 +/- 847.08 km and took 27 +/- 11.20 d (n 1 / 4 3), and the autumn migration covered 2,382.50 +/- 781.35 km and took 39 +/- 15.56 d (n 1 / 4 2). We found no significant difference in migration distance covered or number of traveling days between autumn and spring. We identified 7 stopover sites during spring and 21 stopover sites during autumn migration. Goshawks had strong site fi delity to breeding and wintering sites, and the arrival dates at wintering and breeding sites were similar among years. Our data will aid in the conservation of this species, including guiding decision- making and conservation action plans by providing basic data for the protection of goshawk populations and habitats. Received 11 August 2023. Accepted 14 August 2024.

Avian influenza is a global zoonotic disease influencing bird conservation and public health. Climate and land-cover changes can significantly impact influenza-susceptible species' distribution, thereby influencing avian influenza outbreaks. The Qinghai-Tibetan Plateau (QTP) plays a crucial role in avian influenza virus transmission and is susceptible to environmental changes. Here, we focused on two influenza-susceptible birds, the bar-headed goose (Anser indicus) and brown-headed gull (Chroicocephalus brunnicephalus), to predict their distribution on the QTP under climate and land-cover change scenarios. We integrated satellite tracking, field surveys, and publicly available datasets to collect species occurrence. Then, we utilized Biomod models to predict bird distribution under current and future scenarios. Our results indicated that the distance to water bodies (DW) and the mean temperature of the wettest quarter (BIO 8) significantly influenced the distribution of bar-headed geese and brown-headed gulls. The highly suitable distributions of both species are concentrated in the northeastern QTP and the Changtang Plateau, with only the Qaidam Basin showing a decrease in the future. Their future distribution has roughly doubled, with expansions toward western and higher elevations. We highlighted the influence of climate and land cover changes on bird distribution, and identified key areas of bird distribution, which are also critical areas for future avian influenza monitoring and prevention.

Campylobacter species, especially C. jejuni and C. coli, are the main zoonotic bacteria causing human gastroenteritis. A variety of Campylobacter species has been reported in wild birds, posing a potential avian–human transmission pathway. Currently, there has been little surveillance data on Campylobacter carriage in migratory birds in China. In the current work, fresh fecal droppings from individual migratory birds were collected at four bird wintering/stopover sites in China from May 2020 to March 2021. Nucleic acid was extracted and tested for Campylobacter with PCR-based methods. Overall, 73.8% (329/446) of the samples were positive for Campylobacter, demonstrating location and bird host specificity. Further speciation revealed the presence of C. jejuni, C. coli, C. lari, C. volucris, and an uncharacterized species, which all harbored a variety of virulence factors. Phylogenetic analysis performed on concatenated 16S rRNA-atpA-groEL genes elucidated their genetic relationship, demonstrating both inter- and intra-species diversity. The wide distribution and high diversity of Campylobacter spp. detected in migratory birds in China indicated potential transmission across territories. The existence of virulence factors in all of these species highlighted their public health importance and the necessity of monitoring and controlling Campylobacter and other pathogens carried by migratory birds.

Xinghua Bay is one of the largest wintering sites of the black-faced spoonbill Platalea minor in mainland China. The ecosystem of Xinghua Bay has shown a deteriorating trend with the increasing pressure of economic development in recent decades. To understand the current conservation status of the wintering spoonbills in Xinghua Bay, we collected water samples along the coast of Xinghua Bay and important spoonbill habitats during the wintering period to analyze the pollution degree of 7 target heavy metals and organics. The Nemerow pollution index (NPI), heavy metal pollution index (HPI) and contamination degree (CD) were used to assess the heavy metal pollution levels. The ecological risk index of a target heavy metal ( E f i ) and potential ecological risk index of all target heavy metals (RI) were used to assess the ecological risk of heavy metals levels in Xinghua Bay. Positive matrix factorization (PMF) was used to determine the sources of heavy metals in coastal waters with the EPA PMF5.0 model. The results showed that there was moderate to very heavy pollution by heavy metals and moderate associated ecological risks in Xinghua Bay, in which Hg and Cd were the major heavy metal pollution sources, and the level of organic pollution was of serious concern. The use of fertilizers for cultured shellfish and aquaculture in and around the bay were the major cause of the excessive nitrogen and phosphorus levels, and factories surrounding Xinghua Bay were the major sources of heavy metals and organic pollution. We propose conservation measures to increase black-faced spoonbill population and enhance its habitats.

Migratory birds face diverse threats during migration. Critical stopover sites (CSSs) are essential refueling and resting sites for migratory birds that ensure their complete migration and survival. Therefore, identifying bird migration patterns, routes, and critical habitats is vital for conservation. From 2018-2022, we deployed satellite tracking devices on 30 Bewick's swans (Cygnus columbianus bewickii) wintering in China to determine their migration routes. Using a dynamic Brownian bridge movement model, we identified migration corridors, core movement areas, and CSSs for Bewick's swans. Combining protected area databases and human settlement types, we further assessed the swans' conservation status and human impacts on CSSs. The results showed that Bewick's swans migrated north from their wintering grounds using one of three routes (west, middle, and east), passing through Mongolia to reach the Russian Arctic (breeding grounds) in spring. They followed similar routes during autumn to return to wintering grounds. We found a new middle route within the East Asian-Australasian Flyway (EAAF) and several northward expanded wintering sites. Our study revealed similarities and differences in the spring and autumn migrations, with longer stopover durations in spring due to migration strategies and ice conditions. Moreover, our findings identified the Inner Mongolia region, the Songnen Plain, the Bohai Rim of China, and the main streams of the Lena River and the Ob River of Russia as CSSs for Bewick's swans. However, the conservation status of the CSSs was relatively low; and the situation was more severe in spring than in autumn, only 4.3% of the total area was protected, likely due to the distribution of farmland and urban areas. Specifically, 14.3% of the CSSs in China were in urban areas during spring, while in Mongolia and Russia this figure was less than 1%. Therefore, it is necessary to balance waterbird conservation with sustainable agriculture and urban development. This research contributes to our understanding of the migratory ecology of Bewick's swans wintering in China. The identified migration corridors and CSSs are crucial for the future conservation of swans along the EAAF.

33 Highly pathogenic avian influenza virus (HPAIV) A H5 clade 2.3.4.4 has caused 34 worldwide outbreaks in domestic poultry, occasional spillover to humans, and in35 creasing deaths of diverse species of wild birds since 2014. Wild bird migration 36 is currently acknowledged as an important ecological process contributing to the 37 global dispersal of HPAIV H5. However, it is unclear how seasonal bird migration 38 facilitates global virus dispersal, and which avian species are exposed to HPAI H5 39 clade 2.3.4.4 viruses and where. To shed light on ongoing global outbreaks, we 40 sought to explore these questions through phylodynamic analyses based on empir41 ical data of bird movement tracking and virus genome sequences. First, based on 42 viral phylogeography and bird migration networks, we demonstrate that seasonal 43 bird migration can explain salient features of the global dispersal of clade 2.3.4.4. 44 Second, we detect synchrony between the seasonality of bird annual cycle phases 45 and virus lineage movements. We reveal the differing vulnerable bird orders at 46 geographical origins and destinations of HPAIV H5 lineage movements. Notably, 47 we highlight the potential importance of relatively under-discussed Suliformes and 48 Ciconiiformes, in addition to Anseriformes and Charadriiformes, in virus lineage 49 movements. Our study provides a phylodynamic framework that links the bird 50 movement ecology and genomic epidemiology of avian influenza; it highlights the 51 importance of integrating bird behaviour and life history in avian influenza studies. 52

The Oriental Stork（Ciconia boyciana） is listed as ’Endangered’ on the International Union for the Conservation of Nature（IUCN） Red List of Threatened Species and is classified as a first category nationally protected bird species in China.Understanding this species’ seasonal movements and migration will facilitate effective conservation to promote its population.We tagged 27 Oriental Stork nestlings at Xingkai Lake on the Sanjiang Plain in Heilongjiang Province,China,used GPS tracking to follow them over the periods of 2014-2017 and 2019-2022,and confirmed their detailed migratory routes using the spatial analysis function of ArcGIS 10.7.We discovered four migration routes during autumn migration:one common long-distance migration route in which the storks migrated along the coastline of Bohai Bay to the middle and lower reaches of the Yangtze River for wintering,one short-distance migration route in which the storks wintered in Bohai Bay and two other migration routes in which the storks crossed the Bohai Strait around the Yellow River and wintered in South Korea.There were no significant differences in the number of migration days,residence days,migration distances,number of stopovers and average number of days spent at stopover sites between the autumn and spring migrations（P＞ 0.05）.However,the storks migrated significantly faster in spring than in autumn（P=0.03）.The same individuals did not exhibit a high degree of repetition in their migration timing and route selection in either autumn or spring migration.Even storks from the same nest exhibited considerable between-individual variation in their migration routes.Some important stopover sites were identified,especially in the Bohai Rim Region and on the Songnen Plain,and we further explored the current conservation status at these two important sites.Overall,our results contribute to the understanding of the annual migration,dispersal and protection status of the endangered Oriental Stork and provide a scientific basis for conservation decisions and the development of action plans for this species.

Migratory birds play a critical role in the rapid spread of highly pathogenic avian influenza (HPAI) H5N8 virus clade 2.3.4.4 across Eurasia. Elucidating the timing and pattern of virus transmission is essential therefore for understanding the spatial dissemination of these viruses. In this study, we surveyed >27,000 wild birds in China, tracked the year-round migration patterns of 20 bird species across China since 2006, and generated new HPAI H5N8 virus genomic data. Using this new data set, we investigated the seasonal transmission dynamics of HPAI H5N8 viruses across Eurasia. We found that introductions of HPAI H5N8 viruses to different Eurasian regions were associated with the seasonal migration of wild birds. Moreover, we report a backflow of HPAI H5N8 virus lineages from Europe to Asia, suggesting that Europe acts as both a source and a sink in the global HPAI virus transmission network.

Highly pathogenic avian influenza virus (HPAIV) A H5 clade 2.3.4.4 has caused worldwide outbreaks in domestic poultry, occasional spillover to humans, and increasing deaths of diverse species of wild birds since 2014. Wild bird migration is currently acknowledged as an important ecological process contributing to the global dispersal of HPAIV H5. However, it is unclear how seasonal bird migration facilitates global virus dispersal , and which avian species are exposed to HPAI H5 clade 2.3.4.4 viruses and where . To shed light on ongoing global outbreaks, we sought to explore these questions through phylodynamic analyses based on empirical data of bird movement tracking and virus genome sequences. First, based on viral phylogeography and bird migration networks, we demonstrate that seasonal bird migration can explain salient features of the global dispersal of clade 2.3.4.4. Second, we detect synchrony between the seasonality of bird annual cycle phases and virus lineage movements. We reveal the differing vulnerable bird orders at geographical origins and destinations of HPAIV H5 lineage movements. Notably, we highlight the potential importance of relatively under-discussed Suliformes and Ciconiiformes, in addition to Anseriformes and Charadriiformes, in virus lineage movements. Our study provides a phylodynamic framework that links the bird movement ecology and genomic epidemiology of avian influenza; it highlights the importance of integrating bird behaviour and life history in avian influenza studies. ### Competing Interest Statement The authors have declared no competing interest.

Black-necked cranes (Grus nigricollis) are national first-level protected wild animals in China. Artificial breeding has been adopted by many zoos and reserves to achieve ex-situ conservation of black-necked cranes, but the breeding rate of the species in cages is low. This study used non-invasive methods combined with behavioural observations to investigate changes in sex hormones and glucocorticoid metabolites in the droppings of black-necked cranes during the breeding cycle, with the results showing that (i) levels of estradiol and testosterone in black-necked cranes increased significantly when they entered the breeding period, and these levels could be used as an important physiological indicator to effectively monitor the physiological status of females and males during the reproductive period, thus providing a theoretical basis for the timing of semen collection; (ii) the level of progesterone in the mid-reproduction stage was significantly higher than that in other stages in female black-necked cranes after successful mating, and this level could be an effective indicator of the mating status of female black-necked cranes; (iii) droppings’ glucocorticoid metabolites in the breeding period showed different dynamics between paired and singly caged black-necked cranes, indicating that the physiological phenomenon of reproduction could result in a certain amount of physiological burden on black-necked cranes. These results provide a theoretical basis for the selection of physiological parameters in the artificial breeding of black-necked cranes.

大鸨(Otis tarda)是我国Ⅰ级重点保护野生鸟类,对大鸨重要栖息地种群数量的变化趋势进行研究,将为大鸨及其栖息地的保护提供科学依据.2017年至2020年,对内蒙古图牧吉国家级自然保护区内及周边的大鸨种群数量动态进行了全面调查,共选择33个监测地点,对大鸨的数量、性别和分布地点进行了调查.结果表明,大鸨种群数量从2017年193只增加至2020年253只;大鸨1月的越冬种群数量从2017年67只减少至2019年55只,2020年重新恢复至67只.各月大鸨种群数量呈现较大的变化,数量高峰期分别是5月和10月.12月至次年2月,越冬种群数量50～70只.雌性大鸨从3月开始监测到,数量高峰值出现在4月和5月,达到50～70只,不同的年份略有差别;6月之后数量开始下降,至9月开始略有回升,在10月以后,野外基本观察不到雌性个体.在野外易于观察的4月,2017至2020年4年中雌雄比的平均值是1:2.2017年和2018年,大鸨在马鞍山区域分布较多,数量也较为稳定.然而进入2019年,分布地点减少,这可能与当地人类活动的干扰有关;2020年保护区功能区进行了调整,将2014年调整出保护区范围的马鞍山区域重新划入保护区中,湿地和草地面积均有所增加,大鸨分布地点数量逐渐恢复.针对目前保护区存在的问题,建议采取退耕还草、加强保护空缺管理及禁牧等保护措施对大鸨及其栖息地进行保护.

The 2020 COVID-19 lockdown provides an opportunity to assess how the anthropause affected the behavior of birds. Black-headed gulls ( Larus ridibundus ) wintering at Dianchi Lake (Yunnan Province, southwestern China) prefer to forage on easily accessible human-provided food at various sites along the lake. Following the closure of the lake because of the pandemic, synthetic food was provided at a single location. We expected that the home range size and distribution of gulls would change in response to these changes in food provisioning. A total of 91 gulls were tagged with satellite transmitters in November 2018 and March 2019, and their movements were tracked during the winter months. We analyzed their home range size and spatial distribution in four periods, SCP2019, SOP2019, SCP2020, and SOP2020 (Scenic Opening/Closing Period in 2019/2020), and the difference between SOP2019 and SCP2019 was used as the control group. The eutrophication level in the wintering periods “ Nov. 2018–Apr. 2019 ” and “ Oct. 2019–Apr. 2020 ” was determined using the Normalized Difference Vegetation Index (NDVI), and the coverage ratio of algal blooms and NDVI were used as indicators of the amount of naturally available food. The home range sizes of gulls were reduced in SCP2020 compared with SOP2019, SCP2019, and SOP2020. The gulls were most abundant in the 600–900 m buffer zone and least abundant in the 0–300 m buffer zone in SCP2019; they were most abundant in the 0–300 m buffer zone and least abundant in the 900–2000 m buffer zone in SCP2020. These patterns were consistent with variation in the NDVI and the coverage ratio of algal blooms among buffer zones. Changes in wintering behaviors in SCP2020 relative to other periods suggested that gulls modified their behavior following anthropause-related changes in the distribution and provisioning of food. Our findings provide insights into the role of behavioral plasticity in mediating adaptation to changes in human activities in birds.

Summary Four of China’s six wintering populations of “grey” geese Anser spp. declined during the last decade. In contrast, the Bar-headed Goose A. indicus wintering population in China’s Tibet Autonomous Region more than doubled. During six surveys in Tibet over a 27-year period (1991/92 to 2017/18 winters) we documented an annual growth rate of 6.8% in the Bar-headed Goose population – an increase from approximately 10,100 to 68,100 birds. We propose that in addition to the cessation of hunting, the population growth of Bar-headed Goose is being driven by changes in agricultural land use patterns in Tibet, the establishment of protected areas on the wintering and breeding grounds, and the impacts of climate change across the Tibetan Plateau. Consistent with this hypothesis, the sown area of winter wheat in Tibet has increased and geese have shifted from primarily feeding in crop stubble to planted winter wheat fields. We also found that the most rapid population growth coincided with a 1998 climate regime shift across the Tibetan Plateau resulting in warmer temperatures, an increase in net precipitation, the appearance of new lakes and changes in the water levels and surface area of historical lakes. We suggest that warmer temperatures and high-quality forage on the south-central Tibet wintering grounds may be enhancing over-winter survival, while on the breeding grounds the expansion of lakes and wet meadows is augmenting breeding and brood-rearing habitat.