Abstract
1 Introduction
Habitat loss and degradation are the most pertinent causal factors driving rapid biodiversity decline globally (
Migratory waterbirds include some of the most threatened bird populations in the world, and the identification and protection of key sites and habitats along their flyways has attracted worldwide attention (
In order to formulate an “ecological redline” for China based on waterbird survey data, a handful of studies have presented the broad situation of waterbirds with relevant information (
Sufficient species distribution and abundance data are essential for the effective identification of key habitats, yet the lack of such data is a long-standing barrier to the setting up of conservation plans globally (
In this study, waterbird survey data from coordinated surveys and birdwatchers’ records in the Yangtze River floodplain were used to identify priority sites for conservation based on a standardized framework. The importance of individual priority sites is quantified and a spatio-temporal distribution of waterbird importance is mapped. This study supports the provision of a scientific foundation for waterbird conservation and strategic planning in the Yangtze River floodplain.
2 Data and methodology
2.1 Study area
The Middle and Lower Yangtze floodplain (MLY), with a wetland area of 7.7 × 106 ha, accounts for 17% of the gross wetland area in China (
Figure 1.
2.2 Data collection and processing
Most data used in this study are sourced from coordinated waterbird surveys undertaken in the MLY floodplain in 2004 (
Identifying priority sites using feeding guild as a determinant, rather than single species, may provide more meaningful information for policy makers and managers to promote conservation activities (
2.3 Criteria and thresholds for identifying priority sites and the conservation status of the Middle and Lower Yangtze floodplain for waterbirds
The criteria and population thresholds used to identify priority sites in the MLY floodplain are shown in
Criteria | Source | Thresholds for identifying priority sites |
---|---|---|
Criterion 1 | Criterion 2 for identifying Ramsar sites ( | Regular presence of a single individual for Critically Endangered (CR) and Endangered (EN) species; presence of 30 individuals for Vulnerable species (VU) according to IUCN Red List category |
Criterion 2 | Criterion 6 for identifying Ramsar sites ( | Population exceeds 1% of flyway population (hereafter Ramsar 1% criterion) |
Criterion 3 | Criterion 5 for identifying Ramsar sites ( | Supports 20,000 or more waterbirds |
Table 1.
Criteria and thresholds for identifying priority sites of the Yangtze River floodplain for the conservation of wintering waterbirds
The Importance Index (
where
We also established a Conservation Effectiveness Index (
$C={{C}_{p}}/{{C}_{t}}$
${{C}_{p}}=\sum{_{i=1}^{s}}{{I}_{p}};\ {{C}_{t}}=\sum{_{i=1}^{n}}{{I}_{t}}$
where
2.4 Data processing, priority setting and gap analysis
Globally threatened species were identified according to the International Union for Conservation of Nature and Natural Resources (IUCN) Red List (
3 Results
3.1 Priority sites in the Middle and Lower Yangtze floodplain
Waterbird data from 309 sites throughout the MLY floodplain were analyzed. Overall, 140 sites (45% of the total) were identified as priorities, 120 of which (39% of the total) supported at least one species listed as globally threatened on IUCN’s Red List). In total, 13 globally threatened species were recorded (
No. | Region | Site name | Latitude | Feeding guilds | |||||||
---|---|---|---|---|---|---|---|---|---|---|---|
Longitude | Protected area status | Importance Index | Tuber eaters | Grass eaters | Seed and aquatic vegetation | Invertebrate eaters | Fish eaters | ||||
18 | Anhui | Caizi Lake# | 30.85 | 117.03 | PNR | 115.04 | 52.26 | 7.70 | 5.09 | 38.58 | 11.41 |
19 | Jiangsu | Gaoyou Lake# | 32.86 | 119.35 | NR | 106.36 | 1.62 | 2.42 | 95.80 | 3.37 | 3.15 |
20 | Jiangxi | Dawu Lake# | 29.02 | 116.15 | UN | 105.43 | 90.93 | 1.05 | 1.10 | 6.76 | 5.59 |
21 | Hubei | Chenhu Lake*# | 30.36 | 113.86 | PNR | 98.90 | 4.19 | 19.49 | 24.49 | 18.81 | 31.92 |
22 | Hunan | West Dongting Lake*# | 29.02 | 112.08 | PNR | 93.05 | 1.40 | 1.08 | 9.00 | 4.02 | 77.55 |
23 | Jiangxi | Nanjiang Lake# | 28.95 | 116.48 | UN | 86.02 | 50.46 | 4.95 | 0.80 | 1.89 | 27.92 |
24 | Jiangxi | Zhouxi Lake# | 29.21 | 116.05 | UN | 83.72 | 42.75 | 24.37 | 10.00 | 6.08 | 0.52 |
25 | Shanghai | Chongming Dongtan*# | 31.23 | 121.47 | NNR | 80.06 | 32.91 | 0.12 | 25.07 | 15.37 | 6.59 |
26 | Jiangxi | Kangshan Lake# | 28.89 | 116.58 | NR | 79.15 | 45.12 | 1.99 | 0.41 | 8.05 | 23.58 |
27 | Hubei | Wang Lake* | 29.87 | 115.38 | PNR | 60.55 | 4.55 | 3.28 | 22.95 | 8.45 | 21.32 |
28 | Jiangxi | Jinxi Lake# | 28.66 | 116.35 | UN | 43.48 | 36.51 | 0.69 | 2.95 | 3.00 | 0.33 |
29 | Jiangsu/ | Shijiu Lake# | 31.45 | 118.88 | PNR | 41.23 | 7.07 | 12.97 | 2.39 | 17.00 | 1.80 |
30 | Anhui | Huanghu Lake | 30.02 | 116.52 | PNR | 41.09 | 5.24 | 29.50 | 1.63 | 0.14 | 4.58 |
31 | Jiangxi | Qinglan Lake | 28.43 | 116.20 | NR | 40.80 | 7.77 | 2.53 | 26.14 | 2.27 | 2.09 |
32 | Jiangxi | Chenjia Lake# | 28.66 | 116.35 | UN | 40.55 | 26.87 | 0.25 | 5.55 | 5.66 | 2.22 |
33 | Hubei | Hannan Lake | 30.63 | 114.38 | UN | 40.55 | 0.31 | 1.49 | 28.11 | 0.28 | 10.36 |
34 | Jiangxi | Nanbeigang Lake# | 29.68 | 116.21 | UN | 40.19 | 0.93 | 0.92 | 1.60 | 15.35 | 21.39 |
35 | Anhui | Bohu Lake | 30.21 | 116.36 | PNR | 39.35 | 0.23 | 2.30 | 0.52 | 18.31 | 17.99 |
36 | Anhui | Wuchang Lake | 30.32 | 116.80 | PNR | 38.67 | 10.60 | 23.80 | 1.53 | 0.30 | 2.44 |
37 | Jiangxi | Yugan Nanhu Lake | 28.80 | 116.26 | UN | 35.35 | 26.61 | 0.97 | 2.75 | 3.15 | 1.87 |
38 | Jiangxi | Yugan Donghu Lake | 28.30 | 116.93 | UN | 35.08 | 28.37 | 0.55 | 0.83 | 4.09 | 1.24 |
39 | Jiangxi | Boyang Lake | 29.63 | 116.20 | UN | 34.54 | 2.44 | 1.50 | 1.24 | 23.73 | 5.63 |
40 | Hubei | Dongxi Lake | 30.56 | 114.26 | UN | 30.91 | 0.67 | 6.06 | 2.16 | 6.30 | 15.72 |
41 | Jiangxi | Luojiao Lake# | 29.09 | 116.04 | UN | 30.54 | 17.81 | 6.76 | 2.26 | 0.64 | 3.07 |
42 | Hunan | Hengling Lake | 28.82 | 112.76 | PNR | 29.86 | 0.14 | 1.14 | 12.31 | 6.44 | 9.83 |
43 | Anhui | Fengsha Lake | 30.96 | 117.65 | PNR | 29.36 | 18.16 | 0.33 | 8.05 | 1.21 | 1.61 |
44 | Jiangxi | Duchang Xi Lake# | 29.25 | 116.47 | UN | 29.21 | 5.67 | 3.12 | 3.82 | 15.40 | 1.20 |
45 | Jiangxi | Fanghu Lake# | 29.83 | 116.48 | NR | 29.10 | 11.00 | 7.65 | 5.20 | 3.01 | 2.24 |
46 | Anhui | Baidang Lake | 30.84 | 117.34 | PNR | 28.90 | 11.39 | 4.11 | 2.06 | 10.99 | 0.35 |
47 | Jiangxi | Junshan Lake# | 28.63 | 116.30 | UN | 27.53 | 15.59 | 0.72 | 5.34 | 0.57 | 5.31 |
48 | Jiangxi | Xieshan Lake# | 29.63 | 116.14 | UN | 26.40 | 3.49 | 10.84 | 0.20 | 4.79 | 7.08 |
49 | Jiangxi | Qili Lake | 29.69 | 115.91 | UN | 25.77 | 1.57 | 1.58 | 3.87 | 0.57 | 18.18 |
50 | Jiangxi | Taibo Lake | 30.01 | 116.70 | NR | 25.61 | 5.56 | 4.19 | 9.42 | 4.68 | 1.76 |
51 | Jiangxi | Liaohuachi | 29.34 | 116.00 | NR | 25.43 | 8.81 | 0.92 | 4.52 | 3.97 | 7.21 |
52 | Jiangxi | Gaoqiang Lake | 29.53 | 116.17 | UN | 25.13 | 1.27 | 6.67 | 13.86 | 3.19 | 0.14 |
53 | Hubei | Liangzi Lake | 30.28 | 114.61 | PNR | 25.04 | 3.28 | 0.15 | 13.50 | 1.55 | 6.56 |
Table 2.
(Continued)
One hundred and fifteen sites (37% of the total) met the Ramsar 1% criterion, and eight of these sites (namely Poyang Lake NNR, Nanji wetland NNR, Duchang PNR, Zhuhu Lake and Dalianzi Lake in Jiangxi; East Dongting Lake NNR in Hunan, Shengjin Lake NNR in Anhui, Chenhu Lake in Hubei) had more than 15 species which met the 1% criterion. Twenty-seven sites (8% of the total) supported 5000 or more waterbirds and seven sites supported 20,000 or more waterbirds (criterion 3).
Figure 2.
In total, 140 sites met either the Ramsar criteria or IBA criteria, while only 10 of these sites of them are currently designated as Ramsar sites and 54 are identified as or included in IBAs (Appendix B). The spatial distribution of these sites is shown in
3.2 Spatio-temporal variation of waterbird conservation values in the Yangtze River floodplain
The total Importance Index values from various time periods (1980-2000, 2001-2005, 2006-2010 and 2011-2015) were calculated to present waterbirds abundance changes, as well as waterbirds spatial patterns in the MLY floodplain (
Figure 3.
3.3 Importance Index for different waterbird feeding guilds in the Yangtze River floodplain
We also analyzed the spatial patterns of the Importance Index for various feeding guilds. The results of this analysis show that waterbirds are most dependent on wetland habitats in Jiangxi Province, which had the highest Importance Index for all five feeding guilds (
Figure 4.
3.4 Conservation Effectiveness Index and gaps in the Yangtze River floodplain
The total protected areas in MLY floodplain is 2.07×106 ha, which account for 26.1% of the total wetland areas in this region; most are natural wetlands. After comparative analysis with the distribution of protected areas, we found that 87 of the 140 priority sites (62.1%) identified in this study are located outside of the current protected area network in the MLY.
The status of protected area coverage, along with the size of the protected areas in each region of the MLY, is shown in
Items (Regions) | Anhui | Hubei | Hunan | Jiangsu | Jiangxi | Shanghai | MLY |
---|---|---|---|---|---|---|---|
Number of suevey sites | 32 | 71 | 43 | 64 | 78 | 21 | 309 |
Total Importance Index | 672.44 | 610.66 | 677.87 | 154.27 | 5142.45 | 152.19 | 7409.88 |
Importance Index of sites being | 661.22 | 516.69 | 660.72 | 121.98 | 3557.17 | 86.66 | 5604.44 |
Protected area (103 ha) | 328.51 | 289.44 | 485.64 | 533.47 | 341.94 | 93.88 | 2072.88 |
Proportion of protected area to | 31.5 | 20.0 | 47.6 | 18.9 | 34.6 | 20.2 | 26.90 |
Conservation gap rate (%) | 30.0 | 52.0 | 58.3 | 62.5 | 75.8 | 75.0 | 62.10 |
Conservation Effectiveness Index (%) | 98.3 | 84.6 | 97.5 | 79.1 | 69.1 | 56.9 | 75.63 |
Table 3.
Protected areas and conservation effectiveness indices in the Yangtze River floodplain
To strengthen the protected area network in the MLY, we suggest enhancing the conservation effectiveness by increasing the total Importance Index value for protection and assigning a greater priority to sites with high individual importance values. After further analysis, six sites are proposed as the best for increasing the
Figure 5.
4 Discussion
4.1 Conservation assessment methods in this study
A spatial prioritization method was applied in this study, and wetland priorities, as well as the
Citizen science data and coordinated waterbird survey data were compiled in this study to maximize the accuracy and comprehensiveness of the results. Coordinated waterbird survey data are only available after 2004 in the MLY River and such waterbird survey data, supported by WWF and WWT, from 2004, 2005, 2011 and 2015 were the main data source in this study. Citizen science data (e.g. China Birdwatching Association, CBA) were particularly useful for identifying occurrences of globally threatened species. In the future, we anticipate that a large quantity of data will be generated through citizen-science approaches and rigorous data validation processes will be required during data collation and any follow-up studies (
4.2 Policy implication on waterbirds and their habitats conservation
Waterbirds along the EAAF faithfully utilize a number of traditional wintering sites and studies have shown that the MLY floodplain has been a long-standing wintering habitat for waterbirds along the flyway since at least the 1960s (
Meanwhile, the study also showed that there are 140 sites met either Ramsar or IBA criteria or both, while only ten of them are designated as Ramsar sites and 54 of them identified as or included in current IBAs, which indicates that the value of the MLY floodplain is currently underestimated.
Furthermore, this study also highlighted the unbalanced distribution pattern in the MLY. Jiangxi and Hunan account for almost 60% of the Importance Index for all five feeding guilds. For tuber eaters and invertebrate eaters, they account for in excess of 70% (
Scientific conservation planning coupled with effective governance is essential to achieve successful waterbird conservation (
5 Conclusions
This paper establishes a framework and roadmap for biodiversity assessment based on conservation priority by using wintering waterbirds as an indicator. We proposed the use of Conservation Effectiveness Index (
The main findings of this study are as follows:
The Importance Index of the entire Yangtze River floodplain has decreased slightly from 2001-2005 which implies a decline in overall waterbird abundance, while the spatial pattern of Importance Index in the region is unbalanced; more than 60% of the priority sites are currently located outside protected areas; we therefore recommend further strengthening of the protected area network to better protect declining and internationally important waterbird populations; six sites are the priority for protected status, namely Dalianzi Lake, Linchong Lake, Qihu Lake, Chihu Lake, Chengjiachi and Dawu Lake as their designation increase the total Importance Index (
This study provides support to the implementation and planning of the ecological ‘redline’ along the Yangtze River, as well as the construction of the Yangtze River Ecological Corridor.
Acknowledgement
We sincerely thank WWF-China, the Wildfowl & Wetlands Trust (WWT), HSBC, Coca- Cola, UPS, and Bird report in China for supporting data collection.
References
[1] AmanoT, SzekelyT, SandelB et al. Successful conservation of global waterbird populations depends on effective governance. Nature, 553, 199-202(2018).
[2] AmbalR, DuyaM, CruzM et al. Key biodiversity areas in the Philippines: Priorities for conservation. Journal of Threatened Taxa, 4, 2788-2796(2012).
[3] BarterM, LeiG, CaoL. Waterbird Survey of the Middle and Lower Yangtze River Floodplain (February 2004)(2005).
[4] BarterM, LeiG, CaoL. Waterbird Survey of the Middle and Lower Yangtze River Floodplain (February 2005)(2006).
[5] . Waterbird Research in China.(1994).
[6] BonnA, Gaston KJ. Capturing biodiversity: Selecting priority areas for conservation using different criteria. Biodiversity and Conservation, 14, 1083-1100(2005).
[7] BrooksT, MittermeierR, Da FonsecaG et al. Global biodiversity conservation priorities. Science, 313, 58-61(2006).
[8] CaoL, Fox AD. Birds and people both depend on China’s wetlands. Nature, 460, 173-173(2009).
[9] CaoL, TangS, WangX et al. The importance of eastern China for shorebirds during the non-breeding season. Emu, 109, 170-178(2009).
[10] CaoL, ZhangY, BarterM et al. Anatidae in eastern China during the non-breeding season: Geographical distributions and protection status. Biological Conservation, 143, 650-659(2010).
[11] ChapeS, HarrisonJ, SpaldingM et al. Measuring the extent and effectiveness of protected areas as an indicator for meeting global biodiversity targets. Philosophical Transactions of the Royal Society B, 360, 443-455(2005).
[12] Cohn JP. Citizen science: Can volunteers do real research?. BioScience, 58, 192-197(2008).
[13] Cowling RM, Pressey RL, RougetM et al. A conservation plan for a global biodiversity hotspot - the Cape Floristic Region, South Africa. Biological Conservation, 112, 191-216(2003).
[14] CuiP, WuY, DingH et al. Status of wintering waterbirds at selected locations in China. Waterbirds, 37, 402-409(2014).
[15] FishpoolL, EvansM. Important Bird Areas (IBA) in Africa and associated islands: Priority sites for conservation. Cambridge, UK: BirdLife International (Conservation Series No.11).(2001).
[16] Fox AD, CaoL, ZhangY et al. Declines in the tuber-feeding waterbird guild at Shengjin Lake National Nature Reserve, China: A barometer of submerged macrophyte collapse. Aquatic Conservation: Marine and Freshwater Ecosystems, 21, 82-91(2011).
[17] FreudenbergerL, HobsonP, SchluckM et al. Nature conservation: Priority-setting needs a global change. Biodiversity and Conservation, 22, 1255-1281(2013).
[18] Fu BJ, Yu DD, LuN. Indicator system for biodiversity and ecosystem services evaluation in China. Acta Ecologica Sinica, 37, 341-348(2017).
[19] GaoC, Zhang TL. Eutrophication in a Chinese context: Understanding various physical and socio-economic aspects. Ambio, 39, 385-393(2010).
[20] GuC, HuL, ZhangX et al. Climate change and urbanization in the Yangtze River Delta. Habitat International, 35, 544-552(2011).
[21] GuanL, Lei JL, Zuo AJ et al. Optimizing the timing of water level recession for conservation of wintering geese in Dongting Lake, China. Ecological Engineering, 88, 90-98(2016).
[22] HeinerM, HigginsJ, Li XH et al. Identifying freshwater conservation priorities in the upper Yangtze River Basin. Freshwater Biology, 56, 89-105(2011).
[23] Hoekstra JM, Boucher TM, Ricketts TH et al. Confronting a biome crisis: Global disparities of habitat loss and protection. Ecology Letters, 8, 23-29(2005).
[24] HuR, WenC, GuY et al. A bird’s view of new conservation hotspots in China. Biological Conservation, 211, 47-55(2017).
[25] IwamuraT, Possingham HP, ChadesI et al. Migratory connectivity magnifies the consequences of habitat loss from sea-level rise for shorebird populations. Proceedings of the Royal Society B Biological Sciences, 280, 20130325(2013).
[26] KearJ. Ducks, Geese and Swans: Species Accounts (Cairina to Mergus)(2005).
[27] Kirby JS, Stattersfield AJ, Butchart S HM et al. Key conservation issues for migratory land- and waterbird species on the world’s major flyways. Bird Conservation International, 18, S49-S73(2008).
[28] Kordi MN, O’LearyM. A spatial approach to improve coastal bioregion management of the north western Australia. Ocean & Coastal Management, 127, 26-42(2016).
[29] LeiG, Lei JY, Tao X et al. Report on waterbird survey of the Middle and Lower Yangtze in 2011. In: Living Yangtze Program, World Wide Fund for Nature China.(2011).
[30] Li XY, LiangL, GongP et al. Bird watching in China reveals bird distribution changes. Chinese Science Bulletin, 58, 649-656(2013).
[31] Li Z WD, MundkurT, BakewellD et al. Status of waterbirds in Asia: Results of the Asian waterbird census, 1987-2007. Wetlands International Kuala Lumpur, Malaysia.(2009).
[32] Ma ZJ, CaiR, Li R et al. Managing wetland habitats for waterbirds: An international perspective. Wetlands, 30, 15-27(2010).
[33] Ma ZJ, ChenY, Melville DS et al. Changes in area and number of nature reserves in China. Conservation Biology, 33, 1066-1075(2019).
[34] MackinnonJ, Verkuil YI, MurrayN. IUCN situation analysis on East and Southeast Asian intertidal habitats, with particular reference to the Yellow Sea (including the Bohai Sea). Occasional Paper of the IUCN Species Survival Commission 47.(2012).
[35] ManelS, Williams HC, Ormerod SJ. Evaluating presence-absence models in ecology: The need to account for prevalence. Journal of Applied Ecology, 38, 921-931(2001).
[36] Margules CR, Pressey RL. Systematic conservation planning. Nature, 405, 243-253(2000).
[37] Murray NJ, Fuller RA. Protecting stopover habitat for migratory shorebirds in East Asia. Journal of Ornithology, 156, S217-S225(2015).
[39] Rodrigues A SL, Akcakaya HR, Andelman SJ et al. Global gap analysis: Priority regions for expanding the global protected-area network. Bioscience, 54, 1092-1100(2004).
[40] Runge CA, Watson J EM, Butchart S HM et al. Protected areas and global conservation of migratory birds. Science, 350, 1255-1258(2015).
[41] The Second Investigation of Wetland Resources in China(2014). http://xzsp.forestry.gov.cn/.
[42] SnallT, KindvallO, NilssonJ et al. Evaluating citizen-based presence data for bird monitoring. Biological Conservation, 144, 804-810(2011).
[43] StralbergD, Cameron DR, Reynolds MD et al. Identifying habitat conservation priorities and gaps for migratory shorebirds and waterfowl in California. Biodiversity and Conservation, 20, 19-40(2011).
[44] Sullivan BL, Wood CL, Iliff MJ et al. eBird: A citizen-based bird observation network in the biological sciences. Biological Conservation, 142, 2282-2292(2009).
[45] TantipisanuhN, Gale GA. Identification of biodiversity hotspot in national level: Importance of unpublished data. Global Ecology & Conservation, 13, e00377(2018).
[46] TaoX, Lei JY, Hearn R et al. Report on the Coordinated Survey for Wintering Waterbirds of the Central and Lower Yangtze(2015).
[47] Tavares DC, Guadagnin DL, Moura J FD et al. Environmental and anthropogenic factors structuring waterbird habitats of tropical coastal lagoons: Implications for management. Biological Conservation, 186, 12-21(2015).
[48] VohlandK, Mlambo MC, Horta LD et al. How to ensure a credible and efficient IPBES?. Environmental Science & Policy, 14, 1188-1194(2011).
[49] Wang SM, Dou HS. Lakes in China.(1998).
[50] Wang WJ, Fraser JD, Chen JK. Wintering waterbirds in the middle and lower Yangtze River floodplain: Changes in abundance and distribution. Bird Conservation International, 27, 167-186(2017).
[51] WangY, JiaY, GuanL et al. Optimising hydrological conditions to sustain wintering waterbird populations in Poyang Lake National Natural Reserve: Implications for dam operations. Freshwater Biology, 58, 2366-2379(2013).
[52] WetlandsInternational. Waterbird Population Estimates. 5th ed.(2015). http://wpe.wetlands.org/
[53] WilliamsG, Stroud DA, Hirons G JM et al. Developing a quantitative index as a pragmatic aid to assessing implementation of European Union Birds Directive site protection measures for individual species. Bird Study, 63, 1-12(2016).
[54] Xia SX, Yu XB, MillingtonS et al. Identifying priority sites and gaps for the conservation of migratory waterbirds in China’s coastal wetlands. Biological Conservation, 210, 72-82(2017).
[55] Xia SX, Wang YY, LeiG et al. Restriction of herbivorous waterbird distributions in the middle and lower Yangtze River floodplain in view of hydrological isolation. Wetlands, 37, 79-88(2017).
[56] ZhangL, WangX, Zhang JJ et al. Formulating a list of sites of waterbird conservation significance to contribute to China’s ecological protection red line. Bird Conservation International, 27, 153-166(2017).
[57] ZhangY, Fox AD, CaoL et al. Effects of ecological and anthropogenic factors on waterbird abundance at a Ramsar Site in the Yangtze River floodplain. Ambio, 48, 293-303(2019).
[58] Zhao GH, TianY, Tang ZY et al. Distribution of terrestrial national nature reserves in relation to human activities and natural environments in China. Biodiversity Science, 21, 658-665(2013).
[59] ZhaoM, CongP, BarterM et al. The changing abundance and distribution of Greater White-fronted Geese Anser albifrons in the Yangtze River floodplain: Impacts of recent hydrological changes. Bird Conservation International, 22, 135-143(2012).
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