1) Biology & ecology
- Zhu, B. R., M. A. Verhoeven, C. J. Hassell, K. K. S. Leung, D. Dorofeev, Q. Ma, K. Eiamampai, J. T. Coleman, U. Tserenbat, G. Purev-Ochir, D. V. Li, Z. W. Zhang, and T. Piersma. 2023. Predicting the non-breeding distributions of the two Asian subspecies of Black-tailed Godwit using morphological information. Avian Research 14.
- Maslovsky, K. S., P. N. Maleko, V. V. Pronkevich, J. C. Slaght, and A. N. Powell. 2023. First nests of Endangered Nordmann's Greenshank Tringa guttifer found in over 40 years indicate nesting plasticity. Bird Conservation International 33.
- Loktionov, E. Y., R. A. Digby, N. N. Yakushev, I. A. Shepelev, J. P. Clements, P. S. Tomkovich, N. S. Jarrett, N. A. Clark, R. E. Green, E. G. Lappo, and E. E. Syroechkovskiy. 2023. Evaluating the Impact of Headstarting on the Critically Endangered Spoon-Billed Sandpiper Calidris pygmaea. Diversity-Basel 15.
- Liu, W., X. M. Chen, T. Liang, T. Mu, Y. Z. Ding, Y. Liu, and X. S. Liu. 2023. Varying abundance of microplastics in tissues associates with different foraging strategies of coastal shorebirds in the Yellow Sea. Science of the Total Environment 866.
- Yu, C., R. L. Zhang, L. Z. Zhou, L. Cheng, Y. W. Bao, and Y. W. Song. 2023. Morphological characteristics influence the spatial mixing patterns of shorebirds at Shengjin Lake. Ecology and evolution 13.
- Liu, J., Z. Chai, H. Wang, A. Ivanov, V. Kubelka, R. Freckleton, Z. Zhang, and T. Szekely. 2023. Egg characteristics vary longitudinally in Arctic shorebirds. iScience 26:106928.
- Wang, Y. F., Q. Chen, L. Li, H. F. Ding, J. D. Fraser, J. J. Hou, and W. J. Wang. 2023. The cascading effects of submerged macrophyte collapse on geese at Poyang Lake, China. Freshwater Biology 68:926-939.
- Gilg, O., R. S. A. van Bemmelen, H. Lee, J.-Y. Park, H.-J. Kim, D.-W. Kim, W. Y. Lee, K. Sokolovskis, and D. V. Solovyeva. 2023. Flyways and migratory behaviour of the Vega gull (Larus vegae), a little-known Arctic endemic. PLoS ONE 18:e0281827.
- Liang, Y. Y., B. Dong, P. F. Li, K. Zhang, and X. Gao. 2023. Prediction of overwintering crane population in Poyang Lake wetland based on RS and regression Model, China. Ecological Indicators 149.
- Ansari, A. 2023. Prediction of Climate Change Effects on Siberian Crane (Grus leucogeranus) Habitat Suitability by Using Ensemble Modeling in Asia Wetlands. Wetlands 43.
- Wang, C., G. Wang, T. Li, R. Yu, H. L. Duan, Y. Su, X. M. Wu, Q. Su, R. Lu, and G. Y. Chen. 2023. Habitat seasonal competition and coexistence of typical wetland species in the Yellow Sea-Bohai Gulf Natural Heritage Site. Ecological Indicators 147.
- Gao, M., B. Erdenechimeg, G. Purev-Ochir, A. Gungaa, and Y. M. Guo. 2023. Young, wild, and free-Subadult White-naped Crane (Antigone vipio) exhibit wider home range movements than breeding adults during the summering period. Journal of Ornithology 164:561-572.
2) Conservation & management
- Qu, F. Y., S. Q. Wang, W. Wang, S. H. Liu, S. Y. Li, H. D. Liu, and Z. H. Zhang. 2023. Macrobenthic community structure of Rudong coastal wetland, China: the impact of invasive Spartina alterniflora and its implication for migratory bird conservation. Wetlands Ecology and Management 31:159-168.
- Sun, X. P., J. M. Shen, Y. Xiao, S. Li, and M. C. Cao. 2023. Habitat suitability and potential biological corridors for waterbirds in Yancheng coastal wetland of China. Ecological Indicators 148.
- Lee, J.-H., I.-C. Kim, S.-W. Lee, J.-J. Son, J.-U. Jang, and H.-C. Sung. 2023. International importance of tidal flats in the Republic of Korea as shorebird stopover sites in the East Asian–Australasian flyway. Avian Conservation and Ecology 18.
- Xu, Z. L., B. Dong, C. Wang, X. Gao, H. F. Xu, Z. Z. Wei, Z. P. Lu, and X. Liu. 2023. Construction of international important wetland White-headed crane ecological corridor in Chongming Dongtan, China. Ecological Indicators 149.
- Wei, Z. Z., Z. L. Xu, B. Dong, H. F. Xu, Z. P. Lu, and X. Liu. 2023. Habitat suitability evaluation and ecological corridor construction of wintering cranes in Poyang Lake. Ecological Engineering 189.
3) Avian Influenza /Others
- Takekawa, J. Y., D. J. Prosser, J. D. Sullivan, S. L. Yin, X. X. Wang, G. L. Zhang, and X. M. Xiao. 2023. Potential Effects of Habitat Change on Migratory Bird Movements and Avian Influenza Transmission in the East Asian-Australasian Flyway. Diversity-Basel 15.
- Espano, E., S.-M. Shim, E.-J. Song, J.-H. Nam, S.-H. Jeong, B. T. Padasas, S.-H. Kim, and J.-K. Kim. 2023. Surveillance of avian influenza viruses from 2014 to 2018 in South Korea. Scientific Reports 13:8410.
- Xie, R., W. Wang, Y. Gao, W. Liu, B. Yue, S. Liu, W. Fan, S. Song, and L. Yan. 2023. Evolution and mammalian adaptation of H3 and H10 subtype avian influenza viruses in wild birds in Yancheng Wetland of China. Veterinary Microbiology 279:109669.
- Zhang, H., S. Y. Han, B. Wang, Y. A. Xing, G. H. Yuan, Y. Wang, Z. L. Zhao, G. J. Li, Q. Q. Li, J. C. Pan, W. C. Li, and H. X. He. 2023. Genetic Characterization and Pathogenesis of Avian Influenza Virus H3N8 Isolated from Chinese pond heron in China in 2021. Viruses-Basel 15.
1) Biology & Ecology
Zhu, B. R., Verhoeven, M. A., Hassell, C. J., Leung, K. K. S., Dorofeev, D., Ma, Q., Eiamampai, K., Coleman, J. T., Tserenbat, U., Purev-Ochir, G., Li, D. V., Zhang, Z. W., Piersma, T.
Abstract: Until recently, Limosa limosa melanuroides was thought to be the only subspecies of Black-tailed Godwit in the East Asian-Australasian Flyway. For this reason, all previous occurrences and counts of Black-tailed Godwits in the flyway have been assigned to melanuroides. However, a larger-bodied subspecies, bohaii, has recently been discovered in the flyway. As a result, the occurrence of Black-tailed Godwits in the flyway needs to be recon-sidered such that the specific distribution of each subspecies becomes known. To this end, we developed a simple discriminant function to assign individuals to subspecies based on their bill and wing length. Cross-validation with individuals known to be bohaii or melanuroides, based on molecular analysis, showed the developed func-tion to be 97.7% accurate. When applied to measurements of godwits captured at 22 sites across 9 countries in East-Southeast Asia and Australia, we found that bohaii and melanuroides occurred at most sites and overlapped in their distribution from Kamchatka to Australia. We examined photos from all along the flyway to verify this surprising result, confirming that both subspecies co-occur in most locations. Based on these results, we hypothesise that bohaii and melanuroides from the west of their breeding ranges mostly migrate over Chinese mainland. Birds of both subspecies from the east of their ranges are expected to migrate along the Pacific Ocean. We encourage ringing groups in East-Southeast Asia and Australia to use this simple method to keep adding knowledge about Black-tailed Godwits in the East Asian-Australasian Flyway.
Maslovsky, K. S., Maleko, P. N., Pronkevich, V. V., Slaght, J. C., Powell, A. N.,
Abstract: Knowledge of the breeding ecology of Endangered Nordmann's Greenshank Tringa guttifer is necessary to develop a comprehensive species-specific conservation plan. We found nine greenshank nests in Schaste Bay, Russian Far East during the summers of 2019-2021. These are the first nests found in over 40 years and the only discovered to date on mainland Russia. In contrast to previous nest descriptions, we found greenshanks do not exclusively nest in trees, but also place nests on the ground at the base of mature or sapling larches. Our results indicate greenshanks may be larch obligates during the breeding season, and protecting coastal larch forest ecosystems near bogs, meadows, and mudflats throughout the Russian Far East may be critical to the species' conservation.
Loktionov, E. Y., Digby, R. A., Yakushev, N. N., Shepelev, I. A., Clements, J. P., Tomkovich, P. S., Jarrett, N. S., Clark, N. A., Green, R. E., Lappo, E. G., Syroechkovskiy, E. E.
Abstract: Headstarting is a conservation approach that suggests offering an advantage to a population by improving egg production, survival of embryos and/or juveniles. In this article, we are providing the quantitative data obtained during 10 years for different stages of headstarting (production of eggs per pair, hatching and fledging rates) and the resulting impact (survival to maturity, philopatry rate, sex ratio, apparent survival, growth/decline rate) on the local population of the critically endangered spoon-billed sandpiper. We have shown that headstarting gains are reduced over time from fledging to long-term recruitment to the local breeding population. The possible reasons for this reduction are suggested and discussed. The unexpected finding was a drastic difference in sex ratios of the new recruits, which was about even for headstarting, but strongly male-biased for wild-reared birds. We suggest this happens due to increased mortality of female chicks in nature. We have also shown only headstarting could stop the global decline of the species, particularly once the suggested improvements are implemented and the number of pairs involved is scaled up. Headstarting also had a significant social effect due to the involvement of increasing numbers of people both in the local communities in Chukotka and from many countries on the flyway into searching for marked birds and learning about waders, raising awareness about ecological problems on the East Asian-Australasian Flyway. Thus, it has made the need for conservation actions on the flyway more obvious and sensible.
Liu, W., Chen, X. M., Liang, T., Mu, T., Ding, Y. Z., Liu, Y., Liu, X. S.
Abstract: With the wide application of plastic products, microplastics are now ubiquitous in coastal wetlands, representing a serious threat to the health of coastal organisms. In East Asia, millions of migratory shorebirds depend on the tidal flats of Yellow Sea in China, and they have experienced rapid populations declines due at least partially to the environmental pollution. However, our understanding about the specific exposures and hazards of microplastics, and the factors affecting the bioavailability of microplastics to different shorebird species remains limited, which hinders our ability to address the potential detrimental effects of microplastic accumulation to these fast-disappearing birds. Therefore, this study aims to assess the risk of microplastic exposure in shorebirds, determine the enrichment of microplastics in different tissues, and establish the relationship between shorebirds' foraging strategies and microplastic intake. We extracted and identified microplastics in different tissues sample from the carcasses of 13 individuals in four shore-bird species, and measure the abundance, color, size, and roughness of all microplastics found. Microplastics were found in all species except one red-necked stint (Calidris ruficollis). Polyethylene, silicone, polypropylene, and polyure-thane were the main polymers identified in shorebirds. Microplastics found in shorebirds that use mixed tactile and visual foraging strategy were smaller, less rough, and low in color diversity, compared to those found in shorebirds that forage predominately using visual cues. In addition, ingested microplastics were disproportionately enriched in different tissues; in particular, the abundance and size of microplastics in the digestive tract were significantly higher than those in the pectoral muscles. Understanding the stress of microplastics posed to coastal shorebirds is critical to facilitate more effective and targeted measurements in coastal pollution control.
Morphological characteristics influence the spatial mixing patterns of shorebirds at Shengjin Lake
Yu, C., Zhang, R. L., Zhou, L. Z., Cheng, L., Bao, Y. W., Song, Y. W.
Abstract: SThe coexistence of species with similar ecological niches is one of the core interests of community ecology research. However, how functional feeding traits, including bill size and leg length, determine the niche of mixed flocks of shorebird species has seldomly been studied, as well as, microhabitat variables affect the spatial patterns of availability and the quality of patches for wintering. From October 2016 to March 2017 at Shengjin Lake, Anhui Province, China, we recorded 226 scan samples from the different microhabitats and 93 focal animal videos of four common shorebird species: common greenshank, spotted redshank, Kentish plover, and little ringed plover. We found that the species participating in the mixed groups were different in each microhabitat. The results of the overlap index for microhabitats and foraging techniques between the species were consistent with the morphological characteristics of these species. Kentish and little ringed plovers had the highest Pianka's niche overlap index values of 0.95 and 0.98 for microhabitats and foraging techniques, respectively, whereas common greenshank and spotted redshank had values of 0.78 and 0.89, respectively. Common greenshank and spotted redshank used four foraging techniques: a single probe (PR), multiple probes (MPR), a single peck (PE), and multiple pecks (MPE). Kentish and little ringed plovers only used PE and MPE. The mean bill size, mean leg length, and mean foraging frequency were significantly associated with water depth. The mean bill size and mean leg length were both significantly correlated with the mean foraging frequency of shorebirds. The vegetated area was the most important variable for grouping among shorebirds. We concluded that the four species showed differences in their preferred microhabitats and foraging patterns. Interspecific morphological differences, including bill and leg lengths, resulted in niche differentiation. Thus, effective resource allocation by regional species was realized, and a dynamic balance was achieved by the mixed foraging species. The information on foraging behavior and habitat requirements could be useful in the management of water levels in natural areas and conservation of a diversity of wintering shorebirds.
Egg characteristics vary longitudinally in Arctic shorebirds
Liu, Jin, Chai, Ziwen, Wang, Hui, Ivanov, Anton, Kubelka, Vojtech, Freckleton, Robert, Zhang, Zhengwang, Szekely, Tamas
Abstract: Arctic environments are changing rapidly and if we are to understand the resilience of species to future changes, we need to investigate alterations in their life histories. Egg size and egg shape are key life-history traits, reflecting parental investment as well as influencing future reproductive success. Here we focus on egg characteristics in two Arctic shorebirds, the Dunlin (Calidris alpina) and the Temminck's stint (Calidris temminckii). Using egg photos that encompass their full breeding ranges, we show that egg characteristics exhibit significant longitudinal variations, and the variation in the monogamous species (Dunlin) is significantly greater than the polygamous species (Temminck's stint). Our finding is consistent with the recent "disperse-to-mate" hypothesis which asserts that polygamous species disperse further to find mates than monogamous species, and by doing so they create panmictic populations. Taken together, Arctic shorebirds offer excellent opportunities to understand evolutionary patterns in life history traits.
The cascading effects of submerged macrophyte collapse on geese at Poyang Lake, China
Wang, Y. F., Chen, Q., Li, L., Ding, H. F., Fraser, J. D., Hou, J. J., Wang, W. J.
Abstract: Wetland habitat degradation has become more common in recent decades, leading to an increasing occurrence of food shortages for wild animals. Although the direct effects of food shortages on consumers have been well studied, the cascading effects on interspecific interactions remain poorly understood. Targeted research is required to improve our understanding of the impacts of food shortage on animals and to facilitate the development of conservation plans. Here, we used DNA metabarcoding and field observations of goose foraging behaviour to assess the cascading effects of collapse of tubers of Vallisneria spp., the dominant submerged macrophytes at Poyang Lake, China, on the diet of the swan goose (Anser cygnoides) and on the interspecific competition among goose species, the swan goose, the bean goose (Anser fabalis), and the greater white-fronted goose (Anser albifrons). The metabarcoding analyses were carried out on faecal samples collected in winter 2016/17 and 2018/19, and behavioural observations were conducted in winter 2021/22. Our study elucidated the dietary compositions of the three goose species in greater detail than previously known. When Vallisneria tubers became rare, swan geese switched their foraging focus to Carex spp. and other grassland plants. When tuber abundance rebounded, swan geese resumed tuber foraging, suggesting the superiority of tubers as food for swan geese. Swan geese foraging on Carex, the major foods of bean geese and greater white-fronted geese, potentially increased interspecific competition among goose species. Swan geese increased their pecking rates while bean geese increased time spent foraging apparently to cope with interspecific competition. Given the severe impacts of tuber collapses on waterbirds and the important role of Poyang Lake in waterbird protection, we advocate restoring submerged macrophytes to provide high quality foods for tuber-foraging waterbirds. Our study emphasises that, in addition to directly influencing consumers, food collapses may also influence other species through changes in interspecific interactions. Our study also illustrates the importance of behavioural plasticity to cope with interspecific competition and to respond to environment change.
Flyways and migratory behaviour of the Vega gull (Larus vegae), a little-known Arctic endemic
Gilg, Olivier, van Bemmelen, Rob S. A., Lee, Hansoo, Park, Jin-Young, Kim, Hwa-Jung, Kim, Dong-Won, Lee, Won Y., Sokolovskis, Kristaps, Solovyeva, Diana V.
Abstract: Large gulls are generalist predators that play an important role in Arctic food webs. Describing the migratory patterns and phenology of these predators is essential to understanding how Arctic ecosystems function. However, from all six large Arctic gull taxa, including three long-distance migrants, to date seasonal movements have been studied only in three and with small sample sizes. To document the flyways and migratory behaviour of the Vega gull, a widespread but little-studied Siberian migrant, we monitored 28 individuals with GPS loggers over a mean period of 383 days. Birds used similar routes in spring and autumn, preferring coastal to inland or offshore routes, and travelled 4000-5500 km between their breeding (Siberia) and wintering grounds (mainly the Republic of Korea and Japan). Spring migration mainly occurred in May, and was twice as fast and more synchronized among individuals than autumn migration. Migration bouts mainly occurred during the day and twilight, but rates of travel were always higher during the few night flights. Flight altitudes were nearly always higher during migration bouts than during other bouts, and lower during twilight than during night or day. Altitudes above 2000m were recorded during migrations, when birds made non-stop inland flights over mountain ranges and vast stretches of the boreal forest. Individuals showed high inter-annual consistency in their movements in winter and summer, indicating strong site fidelity to their breeding and wintering sites. Within-individual variation was similar in spring and autumn, but between individual variation was higher in autumn than in spring. Compared to previous studies, our results suggest that the timing of spring migration in large Arctic gulls is likely constrained by snowmelt at breeding grounds, while the duration of migration windows could be related to the proportion of inland versus coastal habitats found along their flyways ('fly-and-forage' strategy). Ongoing environmental changes are hence likely in short term to alter the timing of their migration, and in long term possibly affect the duration if e.g. the resource availability along the route changes in the future.
Liang, Y. Y., Dong, B., Li, P. F., Zhang, K., Gao, X.
Abstract: Reasonable prediction of the crane population that arrives at Poyang Lake Reserve for overwintering every year is of great significance to protect cranes and to provide data about reserve planning. In this paper, considering the time-lag effect of landscape index on crane population, the Landsat satellite images of Poyang Lake wetland in 19 winter periods from 2001 to 2019 were selected. The land-use types of the images were classified by support vector machine to acquire the landscape pattern index. In addition, the Pearson test was adopted to examine the correlation between crane population dynamics and landscape pattern index during overwintering. Finally, the regression model of the crane population was obtained by multivariate linear regression analysis. The results showed that the landscape index had a delayed impact on the crane population, which was significantly correlated with the crane population in the following five years. This effect on different crane population was disparate. The number of siberian cranes and white-naped crane populations showed a downward trend, while that of hooded cranes and common crane populations showed an upward trend. Furthermore, the landscape index affects the crane population to a certain extent, but the landscape pattern has diverse effects on different crane populations. It is suggested that corresponding protection measures be taken for different crane pop-ulations to provide a better habitat for cranes in Poyang Lake.
Ansari, A.
Abstract: The Siberian Crane (Grus leucogeranus) is the third rarest and the most endangered crane species in the world. This study aimed at predicting the effect of climate change on Siberian Crane habitat suitability of breeding range and wintering range in Asia Wetlands by using ensemble modeling under future climate scenarios before the year 2050. In this regard, we used 4 modeling methods, Surface Range Envelop (SRE), Random Forest (RF), Classification Tree Analysis (CTA) and Flexible Discriminant Analysis (FDA) to determine the relationships between the species occurrence and bioclimatic variables under the ensemble framework by using Biomod2 and R software. The results showed that the AUC values were greater than 0.9 and functioning of all models was excellent. The Temperature Seasonality and Temperature Annual Range in the breeding range and Temperature Seasonality and Mean Temperature of Coldest Quarter in the wintering range had the most important role for habitat suitability of this species and respectively 105.64% and 136.27% changes was justified in Siberian Crane habitat suitability. Under RCP2.6 and RCP8.5 climate scenario for Siberian Crane breeding and wintering range, it is possible that climate change will cause a 100% loss of suitable habitat in West Sibera, and a 25.28% loss in Iran and China by 2050. The results of this study can be used in planning and conservation of crane species.
Wang, C., Wang, G., Li, T., Yu, R., Duan, H. L., Su, Y., Wu, X. M., Su, Q., Lu, R., Chen, G. Y.
Abstract: The Natural Heritage Site of the Coast of Yellow Sea-Bohai Gulf of China plays a prominent role in the conservation of global biodiversity. However, with the increase in the number of species inhabiting here, the problem of competition in the habitat space of species within the heritage site has gradually emerged, which has become an important bottleneck restricting the sustainable development of the heritage site. Therefore, this study selected the typical wetland wildlife in this area, red crowned crane (Grus japonensis) and Chinese water deer (Hydropotes inermis), as the study objects. This study used their continuous GPS tracking data to reveal the seasonal laws of habitat selection and suitability of two typical wetland species, and analyze their spatial competition and coexistence relationship. The study results showed that the distribution of home range of the crane and the deer in spring and summer was significantly larger than that in autumn and winter. The area of the sub and most suitable area of the deer in spring was larger than that of the crane. In autumn and winter, the area of the sub and most suitable areas for the deer was small, while the area of the most suitable area for the crane was more than 50 hm2. Except in spring, the two species kept a certain distance from each other in other seasons, and their habitat selection was stable. The optimal threshold range of the crane for D_ree variable was 0-202 m in spring and 0-1200 m in summer and autumn. The deer was affected by vegetation factors in the four seasons. The threshold range of D_ree variable in spring, autumn and winter was 0-80 m, the suitable vegetation height of the deer was 2.31-2.92 m. Finally, this study proposed a refined management pattern of habitat with multiple species coexist.
Gao, M., Erdenechimeg, B., Purev-Ochir, G., Gungaa, A., Guo, Y. M.
Abstract: Understanding space use and how it changes over time is critical in animal ecology. The subadult period is the transition from juvenile to adult. Adults and subadults have different biological requirements in summer, resulting in differential space use patterns. We tagged 66 White-naped Cranes (Antigone vipio) in eastern Mongolia, including 22 adults and 44 hatch-year juveniles, using GPS/GSM trackers from July to August, 2017-2019. The objectives are to characterize and compare space use, especially home ranges of adults and subadults, of White-naped Cranes and to investigate patterns in summer. We split the entire summering period into 6 stages (pre-incubation, incubation/nestling, pre-molting, molting/post-molting, post-fledging, moving to another area before autumn migration) and estimated home ranges, core areas using kernel density estimates (KDE) and minimum convex polygons (MCPs). We found that subadults exhibit wider home range movements than adults and that subadults' ranging areas (corresponding to the home range of adults) decreased from the first half to the second half of the summer. Breeding adults had the smallest home ranges, while one-year-old and two-year-old subadults had equally the largest ranging areas but which decreased significantly when subadults reached sexual maturity at three years old. Throughout the summer, the changing pattern of breeders was generally opposite to that of subadults. All subadult age groups had the largest ranging areas when breeders' home ranges were the smallest during the incubation/nestling stage. This study highlights the difference between adults and subadults and contributes to subadult ecology.
2) Conservation & Management
Qu, F. Y., Wang, S. Q., Wang, W., Liu, S. H., Li, S. Y., Liu, H. D., Zhang, Z. H.,
Abstract: Spartina alterniflora is an invasive plant whose effects on macrobenthic communities are still unclear. The Rudong coast has been invaded by S. alterniflora for years. The effects of S. alterniflora on the macrobenthic community structure have rarely been investigated along the Rudong coast. As the Rudong coastal wetland is an important staging site for migratory birds along the East Asian-Australasian Flyway, an alteration in its macrobenthic community structure may have implications for the conservation of coastal wetland birds and rare waterbirds along that flyway, since macrobenthos are a major food source for these migratory birds. We conducted a survey in the Rudong coastal wetland to compare the macrobenthic community structure and sediment properties between a S. alterniflora-invaded area and a bare mud flat. The results showed that there was no significant difference in the biomass, abundance, species number or biodiversity between the invaded area and the mud flat. However, there were significantly higher heavy metal concentrations in the invaded area, and the community structure was obviously altered. The dominant Mactra veneriformis in the bare mud flat was replaced by another surface-feeding bivalve, Laternula anatina, in the invaded area. Our study suggested that the growth stage of the plants might be an important factor when assessing the impact of S. alterniflora on the macrobenthic community structure. Short and sparse S. alterniflora plants altered the benthic environment and species composition but did not necessarily reduce the biodiversity, abundance or biomass of macrobenthos. The dominant bivalve (L. anatina) living in the sparsely vegetated area was abundant, small, and soft-shelled, which might make it a better food source for the birds than the hard-shelled bivalve (M. veneriformis). Thus, S. alterniflora cannot be simply classified as a threatening factor to the Rudong coastal wetland ecosystem, and its advantages must also be considered.
Sun, X. P., Shen, J. M., Xiao, Y., Li, S., Cao, M. C.
Abstract: Yancheng coastal wetland, as an important part of the East Asian-Australasian Flyway, provided habitat for more than 200 migratory waterbirds by rest and over-winter. After it was listed as a "World Heritage List" in 2019, the protection of waterfowl habitat in Yancheng coastal wetland has attracted extensive attention from the inter-national community. As an indicator species of Yancheng coastal wetland ecosystem health, waterbirds have practical significance for the protection of Yancheng coastal wetlands. Due to the long-term impact of human activities, the waterbird habitats are facing the threat of habitat fragmentation and lose, posing a serious challenge to its survival and diversity. Based on the survey data obtained Gruiformes, Charadriiformes, and Anseriformes waterbirds during the whole years from 2017 to 2021, this paper used the Maxent software for modeling species niches and distributions, a comprehensive evaluation method based on fuzzy mathematics, and Linkage Mapper model to assess the habitat suitability distribution of waterbirds, identify protection gaps and potential biological corridors for waterbirds in Yancheng coastal wetland. The results showed that habitat suitability and anthropogenic disturbance were the decisive factors affecting habitat selection of waterbirds. The suitable habitats for Gruiformes, Charadriiformes, and Anseriformes waterbirds were 23868, 22670, and 24870 ha, respectively. The suitable habitat area of waterbirds was 121,930 ha, concentrated on the study area's central and southern coast. Sheyang estuary was identified as a vital conservation gap in the study area. Meanwhile, biological corridors of a total of 33 waterbirds were identified in the study area. The longest biological corridor was 18.78 km, and the shortest was 0.09 km. Our research can provide scientific support for Yancheng coastal wetland protection and the improvement of waterbird diversity, together with the achievements of an ecological and sustainable situation between environmental conservation and economic development.
Lee, Ju-Hyun, Kim, In-Cheol, Lee, Si-Wan, Son, Jong-Ju, Jang, Jae-Ung, Sung, Ha-Cheol
Abstract: Tidal flats along the southwestern coast of the Republic of Korea are known as internationally important habitats for migratory shorebirds in the East Asian–Australasian Flyway (EAAF). Recent habitat destruction at stopover sites has caused declines in migratory shorebird populations, but the population sizes and habitat use patterns of these species remain poorly understood. We investigated the status of migratory shorebirds using tidal flats in the Republic of Korea. Using population sizes and species diversity, we identified internationally important stopover sites for shorebirds and compared the results of shorebird surveys conducted during the 2014–2015 and 2019–2020 migration period. On Korean tidal flats, 230,000–270,000 shorebirds were counted on their northward migration, and approximately 120,000 individuals were counted on their southward migration. All surveyed areas met internationally important stopover site criteria because they contained more than 0.25% of the shorebird population of one or more species (as opposed to 1% to allow for turnover). We estimated that approximately 20% of the EAAF populations of the Eurasian Curlew (Numenius arquata), Far Eastern Curlew (Numenius madagascariensis), Kentish Plover (Charadrius alexandrinus), and Eurasian Oystercatcher (Haematopus ostralegus) used tidal flats in the Republic of Korea. Importantly, we also confirmed that the critically endangered Spoon-billed Sandpiper (Calidris pygmaea) continued to migrate to the Republic of Korea. These results imply that Korean tidal flats still have great international importance as shorebird stopover sites. Thus, expanding the protection of internationally important stopover sites is necessary to ensure the conservation of migratory shorebirds in the EAAF.
Xu, Z. L., Dong, B., Wang, C., Gao, X., Xu, H. F., Wei, Z. Z., Lu, Z. P., Liu, X.
Abstract: At the Yangtze River estuary, the Chongming Dongtan International Important Wetland is a typical estuary wetland. It is an essential habitat for international migratory birds. The habitat of birds in this area changes rapidly. The ecological corridor is an important means to maintain the stability of the watershed ecosystem and enhance the ecological sustainability of the watershed. It has significant demonstration implications for the preservation of biodiversity and the restoration of ecological functions of wetlands with significant ecological value. In this study, the rare white-headed crane distributed in Chongming Dongtan was taken as the research object, and the land use change in Chongming Dongtan in recent ten years was obtained by ENVI and ArcGIS10.8 software. The ecological sources of the white-headed crane population were screened using morphological spatial pattern analysis (MSPA) and landscape connectivity. Using GIS technology to construct a comprehensive resistance surface, combined with circuit theory, the ecological processes in heterogeneous landscapes are simulated by calculating ' resistance ' or ' current ' to identify important ecological corridors, ecological pinch points, and ecological obstacles. The results showed that the region included 24 ecological sources, 46 ecological corridors, 127 ecological pinch points, and 134 Ecological obstacle points. The habitat in the study area showed a trend of fragmentation. The high-resistance areas of Chongming Dongtan were mainly distributed in low-altitude areas with rapid urbanization and frequent human activities, such as Qiyao Town and Yuxi Village. The ecological corridors of White-headed cranes are mainly distributed in bare flat, reed beaches, grassland, and paddy fields. The optimal threshold of MSPA landscape in the study area is 500 m. At the same time, the ecological function area is optimized and divided into different levels, such as ecological core area, ecological buffer zone, ecological crisscross area, production and living area. This study constructs the ecological corridor of the White-headed crane in Chongming Dongtan from the regional wetland scale, which is helpful to optimize the suitable habitat pattern, and provide the method basis for the habitat protection and ecological network construction of regional wetland habitat.
Wei, Z. Z., Xu, Z. L., Dong, B., Xu, H. F., Lu, Z. P., Liu, X.
Abstract: The construction of ecological corridor is of great significance in alleviating the impact of habitat fragmentation on habitat quality and maintaining the stability of regional ecosystem. Taking overwintering cranes in a typical wetland of Poyang Lake as the research object, the ecological source was screened by calculating landscape connectivity, and the resistance factor and minimum cumulative resistance model were determined by analytic hierarchy process (AHP) to construct an ecological corridor, and the habitat connectivity scheme of over-wintering cranes in a typical wetland of Poyang Lake was discussed. The results showed that: (1) The resistance surface was relatively high in the central, northern, eastern, central, western and southwestern regions of the study area, but relatively low in the eastern, northwestern and southeastern regions of the study area. (2) From 2010 to 2020, the optimal habitat changed from 104.51 km2 to 79.03 km2, and concentrated in the eastern and southern regions of the study area. The least suitable habitat changed from 59.53 km2 to 104.78 km2, and concentrated in the middle line of the study area. (3) In this study, 18 potential ecological corridors were constructed, which were mainly distributed in Fenglin Mountain, Dengjia Village and Banshan Village in the south of the study area and Wangjiadun, Desert Zhou, Houshanzhou and Laoxu Village in the east.
3) Avian Influenza /Others
Takekawa, J. Y., Prosser, D. J., Sullivan, J. D., Yin, S. L., Wang, X. X., Zhang, G. L., Xiao, X. M.
Abstract: Wild waterbirds, and especially wild waterfowl, are considered to be a reservoir for avian influenza viruses, with transmission likely occurring at the agricultural-wildlife interface. In the past few decades, avian influenza has repeatedly emerged in China along the East Asian-Australasian Flyway (EAAF), where extensive habitat conversion has occurred. Rapid environmental changes in the EAAF, especially distributional changes in rice paddy agriculture, have the potential to affect both the movements of wild migratory birds and the likelihood of spillover at the agricultural-wildlife interface. To begin to understand the potential implications such changes may have on waterfowl and disease transmission risk, we created dynamic Brownian Bridge Movement Models (dBBMM) based on waterfowl telemetry data. We used these dBBMM models to create hypothetical scenarios that would predict likely changes in waterfowl distribution relative to recent changes in rice distribution quantified through remote sensing. Our models examined a range of responses in which increased availability of rice paddies would drive increased use by waterfowl and decreased availability would result in decreased use, predicted from empirical data. Results from our scenarios suggested that in southeast China, relatively small decreases in rice agriculture could lead to dramatic loss of stopover habitat, and in northeast China, increases in rice paddies should provide new areas that can be used by waterfowl. Finally, we explored the implications of how such scenarios of changing waterfowl distribution may affect the potential for avian influenza transmission. Our results provide advance understanding of changing disease transmission threats by incorporating real-world data that predicts differences in habitat utilization by migratory birds over time.
Surveillance of avian influenza viruses from 2014 to 2018 in South Korea
Espano, Erica, Shim, Sang-Mu, Song, Eun-Jung, Nam, Jeong-Hyun, Jeong, Seo-Hee, Padasas, Bill Thaddeus, Kim, Sang-Hyun, Kim, Jeong-Ki
Abstract: Surveillance of influenza A viruses (IAVs) among migratory waterfowl is a first step in understanding the ecology, biology, and pathogenicity of IAVs. As part of the nationwide surveillance effort for IAVs in fowl in South Korea, we collected environmental fecal samples in different migratory bird stopover sites in South Korea during the winter seasons within November 2014 through January 2018. We collected a total of 6758 fecal samples, 75 of which were positive for IAV (1.11% positivity). Prevalence of IAVs varied per site and per year. Based on sequencing, the most prevalent hemagglutinin (HA) subtypes were H1, H6, and H5, and the most prevalent neuraminidase (NA) subtypes were N1, N3, and N2. Phylogenetic analyses showed that the genes we isolated clustered with reported isolates collected from other locations along the East Asian-Australasian Flyway. All the H5 and H7 isolates collected in this study were of low pathogenicity. None of the N1 and N2 genes carried amino acid markers of resistance against NA inhibitors. The winter 2016-2017 subset were primarily borne by migratory geese (Anser spp.). These results suggest that majority of the IAVs circulating among migratory wild fowl in South Korea in 2014-2018 were of low pathogenicity. © 2023. The Author(s).
Sun, X. P., Shen, J. M., Xiao, Y., Li, S., Cao, M. C.
Abstract: Yancheng coastal wetland, as an important part of the East Asian-Australasian Flyway, provided habitat for more than 200 migratory waterbirds by rest and over-winter. After it was listed as a "World Heritage List" in 2019, the protection of waterfowl habitat in Yancheng coastal wetland has attracted extensive attention from the inter-national community. As an indicator species of Yancheng coastal wetland ecosystem health, waterbirds have practical significance for the protection of Yancheng coastal wetlands. Due to the long-term impact of human activities, the waterbird habitats are facing the threat of habitat fragmentation and lose, posing a serious chal-lenge to its survival and diversity. Based on the survey data obtained Gruiformes, Charadriiformes, and Anser-iformes waterbirds during the whole years from 2017 to 2021, this paper used the Maxent software for modeling species niches and distributions, a comprehensive evaluation method based on fuzzy mathematics, and Linkage Mapper model to assess the habitat suitability distribution of waterbirds, identify protection gaps and potential biological corridors for waterbirds in Yancheng coastal wetland. The results showed that habitat suitability and anthropogenic disturbance were the decisive factors affecting habitat selection of waterbirds. The suitable habitats for Gruiformes, Charadriiformes, and Anseriformes waterbirds were 23868, 22670, and 24870 ha, respectively. The suitable habitat area of waterbirds was 121,930 ha, concentrated on the study area's central and southern coast. Sheyang estuary was identified as a vital conservation gap in the study area. Meanwhile, biological corridors of a total of 33 waterbirds were identified in the study area. The longest biological corridor was 18.78 km, and the shortest was 0.09 km. Our research can provide scientific support for Yancheng coastal wetland protection and the improvement of waterbird diversity, together with the achievements of an ecological and sustainable situation between environmental conservation and economic development.
Zhang, H., Han, S. Y., Wang, B., Xing, Y. A., Yuan, G. H., Wang, Y., Zhao, Z. L., Li, G. J., Li, Q. Q., Pan, J. C., Li, W. C., He, H. X.
Abstract: In October 2021, a wild bird-origin H3N8 influenza virus-A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8)-was isolated from Chinese pond heron in China. Phylogenetic and molecular analyses were performed to characterize the genetic origin of the H3N8 strain. Phylogenetic analysis revealed that eight gene segments of this avian influenza virus H3N8 belong to Eurasian lineages. HA gene clustered with avian influenza viruses is circulating in poultry in southern China. The NA gene possibly originated from wild ducks in South Korea and has the highest homology (99.3%) with A/Wild duck/South Korea/KNU2020-104/2020 (H3N8), while other internal genes have a complex and wide range of origins. The HA cleavage site is PEKQTR down arrow GLF with one basic amino acid, Q226 and T228 at HA preferentially bind to the alpha-2,3-linked sialic acid receptor, non-deletion of the stalk region in the NA gene and no mutations at E627K and D701N of the PB2 protein, indicating that isolate A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8) was a typical avian influenza with low pathogenicity. However, there are some mutations that may increase pathogenicity and transmission in mammals, such as N30D, T215A of M1 protein, and P42S of NS1 protein. In animal studies, A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8) replicates inefficiently in the mouse lung and does not adapt well to the mammalian host. Overall, A/Chinese pond heron/Jiangxi 5-1/2021 (H3N8) is a novel wild bird-origin H3N8 influenza virus reassortant from influenza viruses of poultry and wild birds. This wild bird-origin avian influenza virus is associated with wild birds along the East Asian-Australasian flyway. Therefore, surveillance of avian influenza viruses in wild birds should be strengthened to assess their mutation and pandemic risk in advance.
