Migration routes, population status and important sites used by the globally threatened Black-faced Spoonbill (Platalea minor): a synthesis of surveys and tracking studies

Abstract Background The Black-faced Spoonbill (Platalea minor) is a globally threatened species, nesting mainly in western Korea with smaller numbers breeding in Liaoning Province, China, and Far East Russia. Recent winter field surveys to estimate the species’ population size were almost totally conducted in coastal areas, but tracking studies showed that some individuals now winter inland. To ensure its long-term survival, we need a more comprehensive assessment of the current distribution and abundance of the species. Methods We combined the most recent count data and satellite tracking information to update existing information about the population abundance and distribution of the Black-faced Spoonbill at all stages of its annual life cycle, and how these have changed during 2004–2020. Results Black-faced Spoonbills mainly breed on the west coast of the Korean peninsula, while immature birds show a wider summer distribution throughout Yellow Sea coastal areas, when a few remain on wintering sites in the south. Combined tracking results and mid-winter counts confirmed known wintering sites on the east and south coasts of China, but showed that the species also winters on wetlands in the Yangtze River floodplain and in Southeast Asia. During 2004–2020, counts of wintering birds in coastal habitats increased from 1198 to 4864, with numbers wintering on the island of Taiwan contributing most to the overall increase. Latest counts found 5222 in 2021. We also identify key wintering and stopover sites as well as their current conservation status. Conclusions This study revised the known summering and wintering ranges of the Black-faced Spoonbill and assessed the conservation status of key sites based on a combination of field survey and satellite tracking data. We recommend prioritisation of further field research to identify and survey inland wintering areas in the Yangtze River floodplain and summering areas of immature birds. More tracking of adult individuals and birds during spring migration is necessary to fill these information gaps. We also suggest establishing a Black-faced Spoonbill monitoring platform to store, share and show real-time distribution range and population abundance data.

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Contrasting habitat use and conservation status of Chinese-wintering and other Eurasian Greater White-fronted Goose (Anser albifrons) populations

Avian Research ◽

10.1186/s40657-021-00306-0 ◽

2021 ◽

Vol 12 (1) ◽

Author(s):

Xueqin Deng ◽

Qingshan Zhao ◽

Junjian Zhang ◽

Andrea Kölzsch ◽

Diana Solovyeva ◽

...

Keyword(s):

Habitat Use ◽

Protected Areas ◽

Annual Cycle ◽

Yangtze River ◽

Conservation Status ◽

East Asian ◽

Agricultural Landscapes ◽

The Yangtze River ◽

River Floodplain ◽

Anser Albifrons

Abstract Background GPS/GSM tracking data were used to contrast use of (i) habitats and (ii) protected areas between three Arctic-nesting Greater White-fronted Geese (Anser albifrons, GWFG) populations throughout the annual cycle. We wished to demonstrate that the East Asian Continental Population (which winters on natural wetlands in the Chinese Yangtze River floodplain and is currently declining) avoids using farmland at multiple wintering sites. We also gathered tracking evidence to support general observations from two increasing population of GWFG, the North Sea-Baltic (which winters in Europe) and the West Pacific (which winter in Korea and Japan) winter mostly within farmland landscapes, using wetlands only for safe night roosts. Methods We tracked 156 GWFG throughout their annual cycle using GPS/GSM transmitters from these three populations to determine migration routes and stopover staging patterns. We used Brownian Bridge Movement Models to generate summer, winter and migration stopover home ranges which we then overlaid in GIS with land cover and protected area boundary at national level to determine habitat use and degree of protection from nature conservation designated areas. Results Data confirmed that 73% of European wintering GWFG homes ranges were from within farmland, compared to 59% in Japan and Korea, but just 5% in China, confirming the heavy winter use of agricultural landscapes by GWFG away from China, and avoidance of farmland at multiple sites within the Yangtze River floodplain. The same GWFG used farmland in northeast China in spring and autumn, confirming their experience of exploiting such habitats at other stages of their annual cycle. Chinese wintering birds showed the greatest overlap with protected areas of all three populations, showing current levels of site safeguard are failing to protect this population. Conclusions Results confirm the need for strategic planning to protect the East Asian Continental GWFG population. While the site protection network in place to protect the species seems adequate, it has failed to stop the declines. Buffalo grazing could serve as one simple strategy to improve the condition of feeding habitats at Dongting Lake and Poyang Lake in the Yangtze, where vast Carex meadows exist. In addition, while we warn against pushing GWFG to winter farmland feeding in China because of the long-term potential to conflict with agricultural interests, we recommend experimental sacrificial, disturbance-free farmland within designated refuge areas adjacent to the Yangtze River floodplain wetland reserves as a manipulative experiment to improve the conservation status of this population in years when natural food sources are limited.

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Priority sites and conservation gaps of wintering waterbirds in the Yangtze River floodplain

Journal of Geographical Sciences ◽

10.1007/s11442-020-1803-y ◽

2020 ◽

Vol 30 (10) ◽

pp. 1617-1632

Author(s):

Shaoxia Xia ◽

Xiubo Yu ◽

Jinyu Lei ◽

Richard Hearn ◽

Bena Smith ◽

...

Keyword(s):

Yangtze River ◽

The Yangtze River ◽

River Floodplain

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Multiscale effects of habitat and surrounding matrices on waterbird diversity in the Yangtze River Floodplain

Landscape Ecology ◽

10.1007/s10980-020-01131-4 ◽

2020 ◽

Author(s):

Boyu Gao ◽

Peng Gong ◽

Wenyuan Zhang ◽

Jun Yang ◽

Yali Si

Keyword(s):

Yangtze River ◽

Structural Features ◽

Ordinary Least Squares ◽

Habitat Connectivity ◽

The Yangtze River ◽

Least Squares Regression ◽

Spatial Error ◽

River Floodplain ◽

Surrounding Landscape ◽

Shape Complexity

Abstract Context With the expansion in urbanization, understanding how biodiversity responds to the altered landscape becomes a major concern. Most studies focus on habitat effects on biodiversity, yet much less attention has been paid to surrounding landscape matrices and their joint effects. Objective We investigated how habitat and landscape matrices affect waterbird diversity across scales in the Yangtze River Floodplain, a typical area with high biodiversity and severe human-wildlife conflict. Methods The compositional and structural features of the landscape were calculated at fine and coarse scales. The ordinary least squares regression model was adopted, following a test showing no significant spatial autocorrelation in the spatial lag and spatial error models, to estimate the relationship between landscape metrics and waterbird diversity. Results Well-connected grassland and shrub surrounded by isolated and regular-shaped developed area maintained higher waterbird diversity at fine scales. Regular-shaped developed area and cropland, irregular-shaped forest, and aggregated distribution of wetland and shrub positively affected waterbird diversity at coarse scales. Conclusions Habitat and landscape matrices jointly affected waterbird diversity. Regular-shaped developed area facilitated higher waterbird diversity and showed the most pronounced effect at coarse scales. The conservation efforts should not only focus on habitat quality and capacity, but also habitat connectivity and complexity when formulating development plans. We suggest planners minimize the expansion of the developed area into critical habitats and leave buffers to maintain habitat connectivity and shape complexity to reduce the disturbance to birds. Our findings provide important insights and practical measures to protect biodiversity in human-dominated landscapes.

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Changes in Tundra Swan Cygnus columbianus bewickii distribution and abundance in the Yangtze River floodplain

Bird Conservation International ◽

10.1017/s0959270911000098 ◽

2011 ◽

Vol 21 (3) ◽

pp. 260-265 ◽

Cited By ~ 11

Author(s):

PEIHAO CONG ◽

LEI CAO ◽

ANTHONY D. FOX ◽

MARK BARTER ◽

EILEEN C. REES ◽

...

Keyword(s):

Water Quality ◽

Yangtze River ◽

Poyang Lake ◽

Submerged Vegetation ◽

Three Gorges ◽

The Yangtze River ◽

Vegetation Productivity ◽

River Floodplain ◽

Cygnus Columbianus ◽

Tundra Swan

Approximately 75% of the East Asian Flyway Tundra Swan Cygnus columbianus bewickii population winters in the Yangtze River floodplain, China. Historically the species was more widely distributed throughout the floodplain but now most of the population is confined to five wetlands in Anhui Province and to Poyang Lake in Jiangxi Province, where the majority (up to 113,000 birds) occur. Within-winter counts suggest that swans congregate at Poyang Lake before dispersing to other sites later in the winter. Counts show large between-year fluctuations, but suggest declines at Shengjin and Fengsha Lakes (both in Anhui) during the last five years. Declines at Shengjin Lake are likely due to decreases in submerged vegetation (particularly tuber-producing Vallisneria, a major food item) perhaps linked to eutrophication. Range contractions throughout the floodplain may also be linked to reductions in submerged vegetation coverage elsewhere. Changes in water quality and lake hydrology post-Three Gorges Dam may have adversely affected submerged vegetation productivity. Key information needs for the effective implementation of conservation measures for Tundra Swans include: (1) annual surveys of all major wintering sites throughout each winter to establish the importance of different sites during the non-breeding period; (2) more information on swan diets at important sites; and (3) an assessment of adverse effects of water quality and lake water levels post-Three Gorges Dam on submerged vegetation productivity at Poyang Lake and other important sites.

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