The southern Jiangsu coast is a critical moulting site for Spoon-billed Sandpiper Calidris pygmaea and Nordmann’s Greenshank Tringa guttifer

Abstract

Summary The extent of intertidal flats in the Yellow Sea region has declined significantly in the past few decades, resulting in severe population declines in several waterbird species. The Yellow Sea region holds the primary stopover sites for many shorebirds during their migration to and from northern breeding grounds. However, the functional roles of these sites in shorebirds’ stopover ecology remain poorly understood. Through field surveys between July and November 2015, we investigated the stopover and moult schedules of migratory shorebirds along the southern Jiangsu coast, eastern China during their southbound migration, with a focus on the ‘Critically Endangered’ Spoon-billed Sandpiper Calidris pygmaea and ‘Endangered’ Nordmann’s Greenshank Tringa guttifer. Long-term count data indicate that both species regularly occur in globally important number in southern Jiangsu coast, constituting 16.67–49.34% and 64.0–80.67% of their global population estimates respectively, and it is highly likely that most adults undergo their primary moult during this southbound migration stopover. Our results show that Spoon-billed Sandpiper and Nordmann’s Greenshank staged for an extended period of time (66 and 84 days, respectively) to complete their primary moult. On average, Spoon-billed Sandpipers and Nordmann’s Greenshanks started moulting primary feathers on 8 August ± 4.52 and 27 July ± 1.56 days respectively, and their moult durations were 72.58 ± 9.08 and 65.09 ± 2.40 days. In addition, some individuals of several other shorebird species including the ‘Endangered’ Great Knot Calidris tenuirostris, ‘Near Threatened’ Bar-tailed Godwit Limosa lapponica, ‘Near Threatened’ Eurasian Curlew Numenius arquata and Greater Sand Plover Charadrius leschenaultii also underwent primary moult. Our work highlights the importance of the southern Jiangsu region as the primary moulting ground for these species, reinforcing that conservation of shorebird habitat including both intertidal flats and supratidal roosting sites in this region is critical to safeguard the future of some highly threatened shorebird species.

Predicting population trends of birds worldwide with big data and machine learning

“…In contrast to regional studies that have reported population declines of migratory birds (Rappole & McDonald 1994, Saino et al 2011, Bairlein 2016, Rosenberg et al 2019, we found that non-migratory birds were more likely to decline globally (Tables 8 and S6). Although migratory birds face unique threats such as habitat loss at stopover sites (Baker et al 2004, Yang et al 2020, their vagility and adoption of new migration routes could enable avoidance of some threats (Dolman & Sutherland 1995). Additionally, we found that non-migratory birds associated with forests or severely fragmented populations were more likely to decline than were non-migrant species without these additional attributes (Tables 8 and S6).…”

“…2004, Yang et al . 2020), their vagility and adoption of new migration routes could enable avoidance of some threats (Dolman & Sutherland 1995). Additionally, we found that non‐migratory birds associated with forests or severely fragmented populations were more likely to decline than were non‐migrant species without these additional attributes (Tables 8 and S6).…”

The Bird Community in a Coastal Wetland in East China and Its Spatial Responses to a Wind Farm

“…Many birds in the EAAF, including the endangered species Calidris pygmaea (critically endangered), Calidris tenuirostris, and Platalea minor, stop in the Rudong coastal wetland during their migration (Ma and Chen, 2018;Yang et al, 2020). Thus, the wetland is well-known to birdwatchers worldwide.…”

“…1a) (Ma et al, 2006); moreover, some terrestrial birds also rest in these wetlands during their migration (Yong et al, 2015). For threatened species in the yway, such as Calidris pygmaea and Tringa guttifer, these wetlands are crucial for future survival (Peng et al, 2017;Yang et al, 2020). In recent decades, bird surveys have been conducted in some coastal wetlands of East China (Ma et al, 2009;Bai et al, 2015;Peng et al, 2017).…”

Risk evaluation of onshore wind farms in relation to wild duck (Anatidae) movements in the Yangtze River Mouth, China

“…However, despite the global importance of wind energy for sustainable development, the negative effects of wind farms on birds need to be taken into consideration [6]. Among the world's eight major migratory waterbird flyways, the East Asian–Australasian flyway (EAAF) supports the highest proportion (19%) of threatened waterbird populations in the world, and is recognised as the most important global waterbird flyway [7]. The EAAF covers a vast region stretching from the Arctic in Siberia and Alaska, southwards through East and South‐East Asia, to Australia and New Zealand.…”