1) Biology & Ecology
- Murray, N. J., T. A. Worthington, P. Bunting, S. Duce, V. Hagger, C. E. Lovelock, R. Lucas, M. I. Saunders, M. Sheaves, M. Spalding, N. J. Waltham, and M. B. Lyons. 2022. High-resolution mapping of losses and gains of Earth's tidal wetlands. Science 376:744-749.
- Kuang, F. L., W. Wu, D. V. Li, C. J. Hassell, G. Maglio, K. S. K. Leung, J. T. Coleman, C. Y. Cheng, P. S. Tomkovich, and Z. J. Ma. 2022. Detecting the non-breeding region and migration route of Whimbrels (Numenius phaeopus rogachevae) in the East Asian-Australasian Flyway. Avian Research 13.
- Lagasse, B. J., R. B. Lanctot, S. Brown, A. G. Dondua, S. Kendall, C. J. Latty, J. R. Liebezeit, E. Y. Loktionov, K. S. Maslovsky, A. I. Matsyna, E. L. Matsyna, R. L. McGuire, D. C. Payer, S. T. Saalfeld, J. C. Slaght, D. V. Solovyeva, P. S. Tomkovich, O. P. Valchuk, and M. B. Wunder. 2022. Migratory network reveals unique spatial-temporal migration dynamics of Dunlin subspecies along the East Asian-Australasian Flyway. PLoS ONE 17.
- Nicol, S., M. J. Cros, N. Peyrard, R. Sabbadin, R. Trepos, R. A. Fuller, and B. K. Woodworth. FlywayNet: A hidden semi-Markov model for inferring the structure of migratory bird networks from count data. Methods in Ecology and Evolution.
- Zhu, B. R., M. A. Verhoeven, N. Velasco, L. Sanchez-Aguilar, Z. W. Zhang, and T. Piersma. 2022. Current breeding distributions and predicted range shifts under climate change in two subspecies of Black-tailed Godwits in Asia. Global Change Biology 28:5416-5426.
- Joo, S., Y. S. Choi, and S. Y. Lee. 2022. Home Range and Habitat Use of the Swan Goose (Anser cygnoides 1758) during Wintering in the Seocheon Tidal Flat, South Korea, Using GPS-Based Telemetry. Animals 12.
- Du, F., S. Y. Wang, Z. Han, X. B. Liu, C. Liu, A. P. Huang, K. Q. Chen, S. L. Zhao, L. Wang, and Z. Jiang. 2022. Impact of hydrological processes on wetland landscapes and wintering migratory birds in a large floodplain lake (Poyang Lake, China). Ecohydrology 15.
- Jang, M., W. J. Shim, G. M. Han, S. Y. Ha, Y. Cho, M. Kim, and S. H. Hong. 2022. Spatial distribution and temporal trends of classical and emerging persistent organic pollutants (POPs) in black-tailed gull (Larus crassirostris) eggs from Korea. Science of the Total Environment 845.
- Hansen, B. D., D. I. Rogers, D. Watkins, D. R. Weller, R. S. Clemens, M. Newman, E. J. Woehler, T. Mundkur, and R. A. Fuller. 2022. Generating population estimates for migratory shorebird species in the world’s largest flyway. Ibis 164:735-749.
2) Conservation & management
- Shi, X., C. Hu, J. Soderholm, J. Chapman, H. F. Mao, K. Cui, Z. J. Ma, D. L. Wu, and R. A. Fuller. Prospects for monitoring bird migration along the East Asian-Australasian Flyway using weather radar. Remote Sensing in Ecology and Conservation.
- Duan, H. L., and X. B. Yu. 2022. Linking landscape characteristics to shorebird habitat quality changes in a key stopover site along the East Asian-Australasian Flyway migratory route. Ecological Indicators 144.
- Xu, H. F., B. Dong, X. Gao, Z. L. Xu, C. Q. Ren, L. Fang, Z. Z. Wei, X. Liu, and Z. P. Lu. Habitat quality assessment of wintering migratory birds in Poyang Lake National Nature Reserve based on InVEST model. Environmental Science and Pollution Research.
- Shumway, N., M. I. Saunders, S. Nicol, R. A. Fuller, N. Ben-Moshe, T. Iwamura, S. W. Kim, N. J. Murray, J. E. M. Watson, and M. Maron. 2022. Exploring the risks and benefits of flexibility in biodiversity offset location in a case study of migratory shorebirds. Conservation biology : the journal of the Society for Conservation Biology:e14031.
- La Sorte, F. A., M. F. J. Aronson, C. A. Lepczyk, and K. G. Horton. 2022. Assessing the combined threats of artificial light at night and air pollution for the world's nocturnally migrating birds. Global Ecology and Biogeography 31:912-924.
- Yang, Y. W., F. F. Sun, K. Liu, J. F. Chen, T. Zheng, and M. Z. Tang. 2022. Influence of heavy metals on Saunders's Gull (Saundersilarus saundersi) reproduction in the Yellow River Estuary: risk assessment and bioaccumulation. Environmental Science and Pollution Research 29:82379-82389.
- Mukherjee, A., S. Pal, P. Das, and S. K. Mukhopadhyay. 2022. Heavy metal exposure to a migratory waterfowl, Northern Pintail (Anas acuta), in two peri-urban wetlands. The Science of the total environment 851:158238.
- Yang, X. T., Z. Z. Duan, S. S. Li, C. X. Zhang, M. Qu, G. D. Hua, X. A. Niu, H. J. Hu, and D. M. Yu. 2022. Factors Driving the Abundance of Wintering Waterbirds in Coastal Areas of Guangdong Province, China. Frontiers in Ecology and Evolution 9.
- Moores, N., H. Jung, H.-J. Kim, B.-Y. Hwang, W.-H. Hur, and A. Borzée. 2022. The Hwaseong Wetlands Reclamation Area and Tidal Flats, Republic of Korea: A Case of Waterbird Conservation in the Yellow Sea. Conservation 2:526-549.
3) Avian Influenza /Others
- Yin, S. L., Y. J. Xu, M. S. Xu, M. C. M. de Jong, M. R. S. Huisman, A. Contina, H. H. T. Prins, Z. Y. X. Huang, and W. F. de Boer. 2022. Habitat loss exacerbates pathogen spread: An Agent-based model of avian influenza infection in migratory waterfowl. PLoS Computational Biology 18.
- Yao, Z. Z., H. B. Zheng, J. S. Xiong, L. P. Ma, R. Gui, G. L. Zhu, Y. Li, G. X. Yang, G. Chen, J. Zhang, and Q. J. Chen. Genetic and Pathogenic Characterization of Avian Influenza Virus in Migratory Birds between 2015 and 2019 in Central China. Microbiology Spectrum.
1) Biology & Ecology
Murray, Nicholas J.; Worthington, Thomas A.; Bunting, Pete; Duce, Stephanie; Hagger, Valerie; Lovelock, Catherine E.; Lucas, Richard; Saunders, Megan I.; Sheaves, Marcus; Spalding, Mark; Waltham, Nathan J.; Lyons, Mitchell B.
Abstract: Tidal wetlands are expected to respond dynamically to global environmental change, but the extent to which wetland losses have been offset by gains remains poorly understood. We developed a global analysis of satellite data to simultaneously monitor change in three highly interconnected intertidal ecosystem types—tidal flats, tidal marshes, and mangroves—from 1999 to 2019. Globally, 13,700 square kilometers of tidal wetlands have been lost, but these have been substantially offset by gains of 9700 km2, leading to a net change of −4000 km2 over two decades. We found that 27% of these losses and gains were associated with direct human activities such as conversion to agriculture and restoration of lost wetlands. All other changes were attributed to indirect drivers, including the effects of coastal processes and climate change.
Fenliang Kuang, Wei Wu, David Li, Chris J. Hassell, Grace Maglio, Kar-Sin K. Leung, Jonathan T. Coleman, Chuyu Cheng, Pavel S. Tomkovich, Zhijun Ma
Abstract: Determining the migration routes and connections of migratory birds at the population level helps clarify intraspecific differences in migration. Five subspecies have been recognized in the Whimbrel (Numenius phaeopus) in Eurasia. Ssp. rogachevae is the most recently described subspecies. It breeds in Central Siberia, while its non-breeding region and migration routes are still unclear. We tracked the migration of Eurasian Whimbrels captured at three non-breeding sites (Moreton Bay in east coast of Australia, Roebuck Bay in Northwest Australia and Sungei Buloh Wetland in Singapore) and two migration stopover sites (Chongming Dongtan and Mai Po Wetland in China). We determined the breeding sites and inferred the subspecies of the tagged birds in the East Asian - Australasian Flyway (EAAF) based on the known breeding distribution of each subspecies. Of the 30 tagged birds, 6 and 21 birds bred in the breeding range of ssp. rogachevae and variegates, respectively; one bred in the presumed transition area between the breeding range of ssp. phaeopus and rogachevae, and two bred in the region between the breeding range of ssp. rogachevae and variegates. The birds that bred in the ssp. rogachevae breeding range spent their non-breeding season in the northern Sumatra, Singapore, East Java and Northwest Australia and mainly stopped over along China's coasts during migration. None of our birds bred in the exclusive breeding range of the phaeopus subspecies. Previous studies have predicted that rogachevae whimbrels migrate along the Central Asian Flyway and spend the non-breeding season in West India and East Africa. We found that at least some rogachevae whimbrels migrate along the EAAF and spend the non-breeding season in Southeast Asia and Australia. The ssp. phaeopus is at best sparsely distributed in the EAAF in the west region, or possibly does not occur at all.
Benjamin J. Lagasse, Richard B. Lanctot, Stephen Brown, Alexei G. Dondua, Steve Kendall, Christopher J. Latty, Joseph R. Liebezeit, Egor Y. Loktionov, Konstantin S. Maslovsky, Alexander I. Matsyna, Ekaterina L. Matsyna, Rebecca L. McGuire10, David C. Payer, Sarah T. Saalfeld, Jonathan C. Slaght, Diana V. Solovyeva, Pavel S. Tomkovich, Olga P. Valchuk, Michael B. Wunder
Abstract: Determining the dynamics of where and when individuals occur is necessary to understand population declines and identify critical areas for populations of conservation concern. However, there are few examples where a spatially and temporally explicit model has been used to evaluate the migratory dynamics of a bird population across its entire annual cycle. We used geolocator-derived migration tracks of 84 Dunlin (Calidris alpina) on the East Asian Australasian Flyway (EAAF) to construct a migratory network describing annual subspecies-specific migration patterns in space and time. We found that Dunlin subspecies exhibited unique patterns of spatial and temporal flyway use. Spatially, C. a. arcticola predominated in regions along the eastern edge of the flyway (e.g., western Alaska and central Japan), whereas C. a. sakhalina predominated in regions along the western edge of the flyway (e.g., N China and inland China). No individual Dunlin that wintered in Japan also wintered in the Yellow Sea, China seas, or inland China, and vice-versa. However, similar proportions of the 4 subspecies used many of the same regions at the center of the flyway (e.g., N Sakhalin Island and the Yellow Sea). Temporally, Dunlin subspecies staggered their south migrations and exhibited little temporal overlap among subspecies within shared migration regions. In contrast, Dunlin subspecies migrated simultaneously during north migration. South migration was also characterized by individuals stopping more often and for more days than during north migration. Taken together, these spatial-temporal migration dynamics indicate Dunlin subspecies may be differentially affected by regional habitat change and population declines according to where and when they occur. We suggest that the migration dynamics presented here are useful for guiding on-the-ground survey efforts to quantify subspecies' use of specific sites, and to estimate subspecies' population sizes and long-term trends. Such studies would significantly advance our understanding of Dunlin space-time dynamics and the coordination of Dunlin conservation actions across the EAAF.
Sam Nicol, Marie-Josée Cros, Nathalie Peyrard, Régis Sabbadin, Ronan Trépos, Richard A Fuller, Bradley K Woodworth
Abstract: Every year, millions of birds migrate between breeding and nonbreeding habitat, but the relative numbers of animals moving between sites are difficult to observe directly. Here we propose FlywayNet, a discrete network model based on observed count data, to determine the most likely migration links between regions using statistical modelling and efficient inference tools. Our approach advances on previous studies by accounting for noisy observations and flexible stopover durations by modelling using interacting hidden semi-Markov Models. In FlywayNet, individual birds sojourn in stopover nodes for a period of time before moving to other nodes with an unknown probability that we aim to estimate. Exact estimation using existing approaches is not possible, so we designed customised versions of the Monte Carlo expectation-maximisation and approximate Bayesian computation algorithms for our model. We compare the efficiency and quality of estimation of these approaches on synthetic data and an applied case study. Our algorithms performed well on benchmark problems, with low absolute error and strong correlation between estimated and known parameters. On a case study using citizen science count data of the Far Eastern Curlew (Numenius madagascariensis), an endangered shorebird from the East Asian-Australasian Flyway, the ABC and MCEM algorithms generated contrasting recommendations due to a difference in optimisation criteria and noise in the data. For ABC, we recovered key features of population-level movements predicted by experts despite the challenges of noisy unstructured data. Understanding connectivity places local conservation efforts and threat mitigation in the global context, yet it has proven difficult to rigorously quantify connectivity at the population level. Our approach provides a flexible framework to infer the structure of migratory networks in birds and other organisms.
Zhu, Bing-Run; Verhoeven, Mo; Velasco Saragoni, Nicolás; Sanchez Aguilar, Lisa; Zhang, Zhengwang; Piersma, Theunis
Abstract: Habitat loss and shifts associated with climate change threaten global biodiversity, with impacts likely to be most pronounced at high latitudes. With the disappearance of the tundra breeding habitats, migratory shorebirds that breed at these high latitudes are likely to be even more vulnerable to climate change than those in temperate regions. We examined this idea using new distributional information on two subspecies of Black-tailed Godwits Limosa limosa in Asia: the northerly, bog-breeding L. l. bohaii and the more southerly, steppe-breeding L. l. melanuroides. Based on breeding locations of tagged and molecularly assayed birds, we modelled the current breeding distributions of the two subspecies with species distribution models, tested those models for robustness and then used them to predict climatically suitable breeding ranges in 2070 according to bioclimatic variables and different climate change scenarios. Our models were robust and showed that climate change is expected to push bohaii into the northern rim of the Eurasian continent. Melanuroides is also expected to shift northward, stopping in the Yablonovyy and Stanovoy Ranges, and breeding elevation is expected to increase. Climatically suitable breeding habitat ranges would shrink to 16% and 11% of the currently estimated ranges of bohaii and melanuroides, respectively. Overall, this study provides the first predictions for the future distributions of two little-known Black-tailed Godwit subspecies and highlights the importance of factoring in shifts in bird distribution when designing climate-proof conservation strategies.
Joo, Sungbae; Choi, Yu-Seong; Lee, Sang-Yeon
Abstract: Simple Summary Due to the rapid environmental changes in the Seocheon Tidal Flat, South Korea, important staging and wintering sites of the vulnerable Far East Russin population of Swan Goose are threatened. To provide practical information for establishing protection strategies based on Swan Goose behavioral characteristics, we estimated core home range and habitat use patterns over time at the Seocheon Tidal Flat during wintering. Based on the GPS tracking data, the core home range and habitat use characteristics of the Swan Goose differed significantly between daytime and nighttime (Day: 59.9 km(2), Night: 40.3 km(2), on average, 100% MCP). In addition, our data indicated that Swan Goose has two important overnight resting areas in the Seocheon Tidal Flat, South Korea, namely the Janggu Bay and sand dune areas in Yubu Island. The Seocheon Tidal Flat is an important staging and wintering site for the Far East Russian population of Swan Goose (Anser cygnoides) in the East Asian-Australasian Flyway. However, rapid environmental changes for tourism in this area can threaten the survival of this vulnerable population by hindering sufficient rest and wintering; therefore, establishing protection strategies based on Swan Goose behavioral characteristics is necessary. Here, we estimated Swan Goose core home ranges and habitat use based on GPS tracking data collected at the Seocheon Tidal Flat in South Korea from 2017-2018. The home range of Swan Geese was estimated to be an area from Yubu Island in the south to Janggu Bay in the north; however, the core home range and habitat use characteristics differed significantly between daytime and nighttime (Day: 59.9 km(2), Night: 40.3 km(2), on average, 100% MCP). During the day (08:00-18:00), Swan Geese mostly spent time resting or feeding on tidal flats, especially those around tidal channels or paddy fields near Janggu Bay, whereas they mostly rested on sand dunes near Yubu Island along with the mudflats at Janggu Bay at night. Our results provide practical information on the habitat use of wintering Swan Geese population over time and indicate that Yubu Island is an important resting place. Hence, these results can contribute to evaluating threats to Swan Geese and establishing management and protection strategies for the Seocheon Tidal Flat, a major wintering site for the Far East Russian population of Swan Geese.
Fei Du, Shiyan Wang, Zhen Han, Xiaobo Liu, Chang Liu, Aiping Huang, Kaiqi Chen, Shilin Zhao, Liang Wang, Zhi Jiang
Abstract: Hydrological processes are an important factor influencing the wetland landscapes and the quality of wintering migratory birds habitat in Poyang Lake. However, most of the research on a small spatiotemporal scale and there is a lack of studies on the impact of hydrological processes on migratory bird habitats. This study analysed the response of the Poyang Lake wetland landscape to low water levels from 1990 to 2016 and determined the relationship between hydrological processes, wetland landscape characteristics and migratory bird habitats. According to the results, the number of days during the study period when the maximum water level was higher than the current water level (MaxDay) and the average water level from the 40th to 50th day prior to the current day (D50) are two critical factors affecting the area of grassland in Poyang Lake. In particular, a D50 value of 9.5-11.0 m is important for maintaining the grassland area and growth of wetland vegetation. Besides, the water level should not exceed 11 m from mid-late October to early November and should be maintained between 7.58 and 7.97 m in mid-late December that can maximize the habitat area of migratory birds. Furthermore, this study used ecological threshold to propose the optimal inundation period of Cyperus rotundus L. community, Leersia japonica community, Polygonum criopolitanum community, Phragmites australis community, Triarrhena lutarioriparia community, Carex spp. community and Phalaris arundinacea community, which are 124-174, 31-101, 199-249, 65-147, 51-121, 110-190 and 175-253 days, respectively.
Mi Jang, Won Joon Shim, Gi Myung Han, Sung Yong Ha, Youna Cho, Miran Kim, Sang Hee Hong
Abstract: This study monitored the spatiotemporal trends of persistent organic pollutants (POPs) contamination along the Korean coasts using eggs of the black-tailed gull, a resident bird that occupies a high trophic position in the marine food web. Black-tailed gull eggs were collected from three breeding islands located in the western (Seoman-do), southern (Hong-do), and eastern (Dok-do) seas of Korea during 2015-2019, and egg contents were analyzed for classical and emerging POPs. Among the target analytes, levels of emerging POPs such as brominated flame retardants (BFRs) and perfluoroalkyl acids (PFAAs) were significantly higher in eggs from Seoman-do than other islands. Global positioning system tracking data show that seagulls from Seoman-do traveled frequently to two neighboring major cities (Incheon and Seoul), indicating that the accumulation of BFRs and PFAAs in bird eggs is directly affected by the pollution characteristics of urban areas. Overall, the ratios of PFAA and BFR to the total POPs in eggs from the islands increased over time, while the proportion of classical POPs decreased. A shift from classical POPs to BFRs and PFAAs in seagull eggs was identified. Interestingly, perfluorooctanoic acid (PFOA), which exhibits limited bioaccumulation, was detected at higher levels in eggs from Seoman-do, indicating widespread use of PFOA and maternal transfer to seabird eggs. Continuous monitoring of PFAAs in marine environments of Korea is needed. This study demonstrates that monitoring of seabird eggs is effective for detecting spatial and temporal trends of POPs in the marine environment, and provides insights into emerging POPs such as PFAAs.
Birgita D. Hansen, Danny I. Rogers, Doug Watkins, Dan R. Weller, Robert S. Clemens, Mike Newman, Eric J. Woehler, Taej Mundkur, Richard A. Fuller
Abstract: Population estimates are widely used to underpin conservation decisions. However, determining accurate population estimates for migratory species is especially challenging, as they are often widespread and it is rarely possible to survey them throughout their full distribution. In the East Asian–Australasian Flyway (EAAF), this problem is compounded by its size (85 million square kilometres) and the number of migratory species it supports (nearly 500). Here, we provide analytical approaches for addressing this problem, presenting a revision of the EAAF population estimates for 37 migratory shorebird species protected under Australian national environmental legislation. Population estimates were generated by (1) summarizing existing count data in the non-breeding range, (2) spatially extrapolating across uncounted areas, and (3) modelling abundance on the basis of estimates of breeding range and density. Expert review was used to adjust modelled estimates, particularly in under-counted areas. There were many gaps in shorebird monitoring data, necessitating substantial use of extrapolation and expert review, the extent of which varied among species. Spatial extrapolation to under-counted areas often produced estimates that were much higher than the observed data, and expert review was used to cross-check and adjust these where necessary. Estimates of population size obtained through analyses of breeding ranges and density indicated that 18 species were poorly represented by counts in the non-breeding season. It was difficult to determine independently the robustness of these estimates, but these breeding ground estimates were considered the best available data for 10 species that mostly use poorly surveyed freshwater or pelagic habitats in the non-breeding season. We discuss the rationale and limitations of these approaches to population estimation, and how they could be modified for other applications. Data available for population estimates will vary in quality and extent among species, regions and migration stage, and approaches need to be flexible enough to provide useful information for conservation policy and planning.
2) Conservation & Management
Xu Shi, Cheng Hu, Joshua Soderholm, Jason Chapman, Huafeng Mao, Kai Cui, Zhijun Ma, Dongli Wu, Richard A. Fuller
Abstract: Each year, billions of birds migrate across the globe, and interpretation of weather radar signals is increasingly being used to document the spatial and temporal migration patterns in Europe and America. Such approaches are yet to be applied in the East Asian-Australasian Flyway (EAAF), one of the most species-rich and threatened flyways in the world. Logistical challenges limit direct on-ground monitoring of migratory birds in many parts of the EAAF, resulting in knowledge gaps on population status and site use that limit evidence-based conservation planning. Weather radar data have great potential for achieving comprehensive migratory bird monitoring along the EAAF. In this study, we discuss the feasibility and challenges of using weather radar to complement on-ground bird migration surveys in the flyway. We summarize the location, capacity and data availability of weather radars across EAAF countries, as well as the spatial coverage of the radars with respect to migrants' geographic distribution and migration hotspots along the flyway, with an exemplar analysis of biological movement patterns extracted from Chinese weather radars. There are more than 430 weather radars in EAAF countries, covering on average half of bird species' passage and non-breeding distributions, as well as 70% of internationally important sites for migratory shorebirds. We conclude that the weather radar network could be a powerful resource for monitoring bird movements over the full annual cycle throughout much of the EAAF, providing estimates of migration traffic rates, site use, and long-term population trends, especially in remote and less-surveyed regions. Analyses of weather radar data would complement existing ornithological surveys and help understand the past and present status of the avian community in a highly threatened flyway.
Houlang Duan, Xiubo Yu
Abstract: The area and quality of shorebird stopover habitat along the key East Asian-Australasian Flyway migratory route has decreased. The cause is not fully understood. We apply an InVEST (Integrated Valuation of Ecosystem Services and Trade-offs) model to examine shorebird habitat quality between 1975 and 2020 in the Yellow River Delta (YRD), and link landscape characteristics to habitat quality. Mean habitat quality declined from 0.42 to 0.20, areas of high habitat quality declined by 31.75%, and those of low and medium quality increased by 18.67% and 12.98%, respectively. Increased percentages of landscape (PLAND) and largest patch index (LPI) for city, industrial mining, reservoir/pond, and mariculture land-usage categories, and decreased PLAND and LPI for coastal wetlands significantly contribute to decreased mean habitat quality. Increased mean patch area (AREA_MN) and area-weighted mean patch fractal dimension (FRAC_AM) for city and reservoir/pond also greatly contribute to habitat quality decrease. For Spartina alterniflora, increased PLAND, LPI, number of patches (NP), AREA_MN, FRAC_AM and aggregation index (AI) contribute to reduced mean habitat quality. In the Shandong YRD National Nature Reserve, the impact of increased S. alterniflora invasion on shorebird habitat quality is greater than that of other forms of land use. In contrast, in Non-Reserve, the increased area of degraded land poses a greater threat to habitat quality than other factors. Managing S. alterniflora in Reserve, and reducing human activity in Non-Reserve, is required to curtail further decreases in habitat quality.
Haifeng Xu, Bin Dong, Xiang Gao, Zhili Xu, Chunqiu Ren, Lei Fang, Zezhu Wei, Xiao Liu & Zhipeng Lu
Abstract: Poyang Lake National Nature Reserve (PLNNR) is an important resting place for wintering migratory birds on the East Asian-Australasian Flyway (EAAF). In recent years, due to human activities and climate change, the area of wetlands has shown a downward trend, and the number and habitat of wintering migratory birds have been threatened. It is urgent to evaluate the habitat quality of wintering migratory birds in PLNNR. Therefore, the InVEST model and landscape index were used to evaluate the habitat quality of wintering migratory birds, and the grey correlation theory was used to reveal the response of typical wintering migratory bird population to habitat quality. The results showed that the habitat quality of the PLNNR was still at a high level, but showed a downward trend, with the average index of habitat quality decreasing from 0.872 to 0.817. The area of the highest quality habitat decreased by 3394.92 hm(2), the area of the lowest, low, and medium quality habitats increased by 3112.11 hm(2), and the area of the high quality habitat remained stable. The lowest, low, and medium quality habitat expanded from the middle to the south of the PLNNR mainly because of the expansion of construction land and cultivated land. The area with deterioration in habitat quality was 10,477.53 hm(2), mainly concentrated in the center and south of the PLNNR. The area with restoration in habitat quality was 6148.26 hm(2), mainly concentrated in the Bang Lake and Dacha Lake. The area with no change in habitat quality remained stable. The fragmentation degree and shape complexity of highest and high quality habitats increased, dominance degree and connectivity decreased, and the landscape pattern of habitat quality showed a downward trend. Typical wintering migratory birds have a strong correlation with highest, high, and low habitat quality, and there is a downward trend with the deterioration of habitat quality. Finally, this paper puts forward constructive suggestions on the degradation of habitat quality caused by land-use change.
Nicole Shumway, Megan I Saunders, Sam Nicol, Richard A Fulle, Noam Ben-Moshe, Takuya Iwamura, Sun W Kim, Nicholas J Murray, James E M Watson, Martine Maron
Abstract: Biodiversity offsets aim to counterbalance the residual impacts of development on species and ecosystems. Guidance documents explicitly recommend that biodiversity offset actions be located close to the location of impact because of higher potential for similar ecological conditions, but allowing greater spatial flexibility has been proposed. We examined the circumstances under which offsets distant from the impact location could be more likely to achieve no net loss or provide better ecological outcomes than offsets close to the impact area. We applied a graphical model for migratory shorebirds in the East Asian-Australasian Flyway as a case study to explore the problems that arise when incorporating spatial flexibility into offset planning. Spatially flexible offsets may alleviate impacts more effectively than local offsets; however, the risks involved can be substantial. For our case study, there were inadequate data to make robust conclusions about the effectiveness and equivalence of distant habitat-based offsets for migratory shorebirds. Decisions around offset placement should be driven by the potential to achieve equivalent ecological outcomes; however, when considering more distant offsets, there is a need to evaluate the likely increased risks alongside the potential benefits. Although spatially flexible offsets have the potential to provide more cost-effective biodiversity outcomes and more cobenefits, our case study showed the difficulty of demonstrating these benefits in practice and the potential risks that need to be considered to ensure effective offset placement.
Frank A. La Sorte, Myla F. J. Aronson, Christopher A. Lepczyk, Kyle G. Horton
Abstract: Aim Two important environmental hazards for nocturnally migrating birds are artificial light at night (ALAN) and air pollution, with ambient fine particulate matter (PM2.5) considered to be especially harmful. Nocturnally migrating birds are attracted to ALAN during seasonal migration, which could increase exposure to PM2.5. Here, we examine PM2.5 concentrations and PM2.5 trends and the spatial correlation between ALAN and PM2.5 within the geographical ranges of the world's nocturnally migrating birds. Location Global. Time period 1998-2018. Major taxa studied Nocturnally migrating birds. Methods We intersected a global database of annual mean PM2.5 concentrations over a 21-year period (1998-2018) with the geographical ranges (breeding, non-breeding and regions of passage) of 225 nocturnally migrating bird species in three migration flyways (Americas, n = 143; Africa-Europe, n = 36; and East Asia-Australia, n = 46). For each species, we estimated PM2.5 concentrations and trends and measured the correlation between ALAN and PM2.5, which we summarized by season and flyway. Results Correlations between ALAN and PM2.5 were significantly positive across all seasons and flyways. The East Asia-Australia flyway had the strongest ALAN-PM2.5 correlations within regions of passage, the highest PM2.5 concentrations across all three seasons and the strongest positive PM2.5 trends on the non-breeding grounds and within regions of passage. The Americas flyway had the strongest negative air pollution trends on the non-breeding grounds and within regions of passage. The breeding grounds had similarly negative air pollution trends within the three flyways. Main conclusions The combined threats of ALAN and air pollution are greatest and likely to be increasing within the East Asia-Australia flyway and lowest and likely to be decreasing within the Americas and Africa-Europe flyways. Reversing PM2.5 trends in the East Asia-Australia flyway and maintaining negative PM2.5 trends in the Americas and Africa-Europe flyways while reducing ALAN levels would likely be beneficial for the nocturnally migrating bird populations in each region.
Yuewei Yang, Fengfei Sun, Kai Liu, Junfeng Chen, Tong Zheng & Meizhen Tang
Abstract: The heavy metal migration in the food chain exerted significant influence on the survival and reproduction of wetland birds and then disturbed and threatened the balance and health of the estuary ecosystem. In this study, the concentration of heavy metals (Cu, Cr, Fe, Mn, Cd, Ni, and Pb) in surface sediment of the Yellow River Estuary (YRE), the food sources of Saunders's Gull (Saundersilarus saundersi) nestlings, and the egg structure of birds were analyzed to determine the bioaccumulation and reproductive influence on wetland bird. The results indicated higher mean concentrations of sediment heavy metals than their corresponding background values in 2019, with the exception of Fe. Notably, the metal Cd exceeded geochemical background value by 1561.5% in 2018 and 1353.9% in 2019, resulting in severe contamination associated with Cd in the YRE (with geo-accumulation indexes of 3.44 and 3.23). Biomagnification factor (BMF) of heavy metals demonstrated that the concentrations of Cr, Ni, and Cu decreased with the trophic level rising while Cd, Mn, Pb, and Fe denoted bio-amplification in the food chain. The residual indexes showed that the food resources of Saunders's Gull were polluted by Cr, Pb, and Cu. Additionally, a higher enrichment of heavy metals was observed in the eggshell membrane. Metal concentrations had significant influences on the reproduction of Saunders's Gull, except for Cd, among which Ni, Pb, Cu, and Fe may have contributed to the reproductive success of birds, whereas the hatching failure of birds may be caused by Cr and Mn. It is of great importance to monitor the contamination of the wetland ecosystem and provide effective management and protection of the wildlife in the YRE.
Mukherjee, Arkajyoti; Pal, Sudin; Das, Papita; Mukhopadhyay, Subhra Kumar
Abstract: In this study, the heavy metal exposure risk model was employed to assess the exposure risk to a predominantly herbivore waterfowl, Northern Pintail, wintering in two wetland habitats in the Purulia district of West Bengal, located on overlapping Central Asian Flyway (CAF) and East Asian-Australasian Flyway (EAAF). Both wetlands were important staging and roosting grounds for migratory waterfowl for ages. The exposure model was used to quantify the risk of exposure to metals through oral ingestion. Exposure doses of Cu, Zn, Pb, and Cr through food plants ingestion and food-associated sediment consumption pathways were two potent sources of heavy metal exposure in the waterfowl under study. Exposure through water intake was ignored as metals were either of negligible concentrations or below the detection limit in water samples. Heavy metal concentrations showed significant positive correlations between bottom sediment and plant at both sites. At Purulia Sahebbandh (Site 1), the total exposure dose of all four metals was much higher than their conforming tolerable daily intake (TDI), and thereby, the metals might pose threats to the migratory wintering herbivorous waterfowl populations. However, in Adra Sahebbandh (Site 2), total exposure doses of Pb, Zn and Cu were much below their corresponding TDI. The Hazard Quotient (HQ) of Cr was highest followed by nonessential toxic Pb and these two elements could be considered as priority pollutants at Site 1. Prioritize threats were decreased in the following sequence: Cr > Pb > Cu > Zn at Site 1 and Cr > Zn > Pb > Cu at Site 2. Hazard Index was found to be >5 at Site 1 and for much higher metal loads a significant correlation between metal concentrations in plants, bottom sediment and exposure doses were also recorded. Therefore, the peri-urban Purulia Sahebbandh wetland could immediately be considered for risk control and demanded holistic management of important waterfowl habitats.
Xitao Yang, Zhizhao Duan, Shuangshuang Li, Chunxia Zhang, Ming Qu, Guodong Hua, Xiaonan Niu, Huijian Hu and Dongmei Yu
Abstract: The diverse habitat of the coastal areas of Guangdong, China, supports important waterbird populations, thereby contributing to the conservation of waterbirds in China and globally. The sensitivity of different waterbirds to environmental driving factors results in differences in habitat selection, which in combination affect waterbird abundance. This study investigated the effects of environmental and human disturbance factors on the abundance of waterbirds based on a survey of waterbirds in coastal areas of Guangdong Province, China. Redundancy analysis (RDA) was mainly used to study the relationships between the abundance of waterbirds and environmental and human factors. The results showed that the areas of mangrove and tidal flats were the main factors driving the abundance of shorebirds and open water waterbirds, whereas the areas of mangrove and water bodies were the main factors driving the abundance of wading birds and waterfowl, respectively. Road length and the areas of construction land were found to have negative effects on the abundance of waterbirds. A waterbird protection and management strategy was proposed based on the results.
Nial Moores, Hanchul Jung, Hwa-Jung Kim, Bo-Yeon Hwang, Wee-Haeng Hur and Amaël Borzée
Abstract: The reclamation of tidal flats is implicated in the declines of a large number of migratory waterbird species along the East Asia-Australasian Flyway, and has resulted in the assessment of Yellow Sea tidal flats as an Endangered habitat by the IUCN. Created in their present form by large-scale reclamation, the Hwaseong Wetlands on the Yellow Sea coast of the Republic of Korea are comprised of tidal flats, a large reclamation lake, and extensive areas of rice-fields and fallow land. As part of preparation for increased protections for these wetlands, we conducted bird surveys between late June 2020 and mid-June 2021. During this period, we recorded more than 150,000 waterbirds in the wetland and concentrations of 1% or more of 25 populations of waterbird. We also recorded a total of 16 globally threatened wetland species. As at many other coastal wetlands in the Yellow Sea, tidal flat obligate waterbird species used the tidal flats for foraging; and roosted in artificial wetlands which had been created through the reclamation process. The extensive areas of rice-field and other freshwater habitats in the Hwaseong Wetlands were also internationally important in their own right, supporting globally threatened amphibians and internationally important concentrations of foraging geese and floodplain-associated waterbird species. The movements of waterbirds between foraging and roosting areas we recorded make clear that conservation of the site’s biodiversity either as a Ramsar site or within a serial World Heritage Property would require protection of all the contiguous tidal flats and also of the most biodiverse rice-field and freshwater wetland areas. As elsewhere in the coastal zone of the Republic of Korea, this would first require the support of local stakeholders and also a reduction in jurisdictional issues between various local and national decision-making bodies.
3) Avian Influenza /Others
Shenglai Yin, Yanjie Xu, Mingshuai Xu, Mart C M de Jong, Mees R S Huisman, Andrea Contina, Herbert H T Prins, Zheng Y X Huang, Willem F de Boer
Abstract: Habitat availability determines the distribution of migratory waterfowl along their flyway, which further influences the transmission and spatial spread of avian influenza viruses (ATVs). The extensive habitat loss in the East Asian-Australasian Flyway (EAAF) may have potentially altered the virus spread and transmission, but those consequences are rarely studied. We constructed 6 fall migration networks that differed in their level of habitat loss, wherein an increase in habitat loss resulted in smaller networks with fewer sites and links. We integrated an agent-based model and a susceptible-infected-recovered model to simulate waterfowl migration and AIV transmission. We found that extensive habitat loss in the EAAF can 1) relocate the outbreaks northwards, responding to the distribution changes of wintering waterfowl geese, 2) increase the outbreak risk in remaining sites due to larger goose congregations, and 3) facilitate AIV transmission in the migratory population. In addition, our modeling output was in line with the predictions from the concept of "migratory escape", i.e., the migration allows the geese to "escape" from the location where infection risk is high, affecting the pattern of infection prevalence in the waterfowl population. Our modeling shed light on the potential consequences of habitat loss in spreading and transmitting AIV at the flyway scale and suggested the driving mechanisms behind these effects, indicating the importance of conservation in changing spatial and temporal patterns of AIV outbreaks.
Zhongzi Yao, Huabin Zheng, Jiasong Xiong, Liping Ma, Rui Gui, Gongliang Zhu, Yong Li, Guoxiang Yang, Guang Chen, Jun Zhang, and Quanjiao Chen
Abstract: Active surveillance of avian influenza virus (AIV) in wetlands and lakes is important for exploring the gene pool in wild birds. Through active surveillance from 2015 through 2019, 10,900 samples from wild birds in central China were collected, and 89 AIVs were isolated, including 2 subtypes of highly pathogenic AIV and 12 of low-pathogenic AIV; H9N2 and H6Ny were the dominant subtypes. Phylogenetic analysis of the isolates demonstrated that extensive intersubtype reassortments and frequent intercontinental gene exchange occurred in AIVs. AIV gene segments persistently circulated in several migration seasons, but interseasonal persistence of the whole genome was rare. The whole genomes of one H6N6 and polymerase basic 2 (PB2), polymerase acidic (PA), hemagglutinin (HA), neuraminidase (NA), M, and nonstructural (NS) genes of one H9N2 virus were found to be of poultry origin, suggesting a spillover of AIVs from poultry to wild birds. Importantly, one H9N2 virus only bound to human-type receptor, and one H1N1, four H6, and seven H9N2 viruses possessed dual receptor-binding capacity. Nineteen of 20 representative viruses tested could replicate in the lungs of mice without preadaptation, which poses a clear threat of infection in humans. Together, our study highlights the need for intensive AIV surveillance. IMPORTANCE Influenza virus surveillance in wild birds plays an important role in the early recognition and control of the virus. However, the AIV gene pool in wild birds in central China along the East Asian-Australasian flyway has not been well studied. Here, we conducted a 5-year AIV active surveillance in this region. Our data revealed the long-term circulation and prevalence of AIVs in wild birds in central China, and we observed that intercontinental gene exchange of AIVs is more frequent and continuous than previously thought. Spillover events from poultry to wild bird were observed in H6 and H9 viruses. In addition, in 20 representative viruses, 12 viruses could bind human-type receptors, and 19 viruses could replicate in mice without preadaption. Our work highlights the potential threat of wild bird AIVs to public health. Influenza virus surveillance in wild birds plays an important role in the early recognition and control of the virus. However, the AIV gene pool in wild birds in central China along the East Asian-Australasian flyway has not been well studied.