Work

Spatial and temporal dynamics of wintering waterbird communities in South Korea along the East Asian–Australasian flyway

Year: 2026

Type: article

Abstract: Wetlands underpin biodiversity and vital ecosystem services but are rapidly altered by climate and land-use change. We analyzed nationwide mid-winter counts from the Winter Waterbird Census of Korea (WWCK) to resolve spatial and temporal dynamics of wintering waterbird communities across South Korea from 2010 to 2020. Using a self-organizing map (SOM), we classified 208 sites into six ecologically interpretable assemblages spanning coastal, riverine, lacustrine, tidal-flat, and Jeju Island/southern mosaic. Indicator species were identified using the Indicator Value (IndVal) method, which quantifies species’ associations with specific assemblages, and assemblage-level trajectories were quantified with Multispecies Indices (MSIs; 2010 = 1.0). Trajectories diverged among assemblages. Coastal, seabird-dominated sites (cluster 1) declined steadily (−2.8% yr⁻¹; −41.3% overall), whereas large river–lake systems (cluster 4) and the Jeju/southern mosaic (cluster 6) increased (+5.0% yr⁻¹; +60.1% overall and +3.0% yr⁻¹; +30.4% overall, respectively). Tidal-flat communities (cluster 5) were broadly stable (+0.1% yr⁻¹; +3.6% overall). Generalized linear models related MSIs to human and environmental factors, revealing negative associations with aquaculture (cluster 1), salt pans (cluster 5), and streams & rivers (cluster 4), and a positive association with rice-field extent in inland systems (cluster 4). These results show that wintering community change is structured by habitat context and human use. We recommend habitat-tailored actions: bycatch mitigation and aquaculture management along coasts; protection and water-level management at reservoirs and rivers; wildlife-friendly rice-field practices; and maintenance of Yellow Sea tidal flats and roost–forage linkages. Implemented within East Asian–Australasian Flyway partnerships, such measures can help stabilize or reverse declines in migratory waterbirds.

Source: Global Ecology and Conservation

DOI: 10.1016/j.gecco.2026.e04191