Habitat

The Spoon-billed Sandpiper inhabits a very specific breeding habitat: along the sea coasts of Chukotka where there are sandy ridges or gravel or pebble spits sparsely vegetated by mosses, dwarf willows and grasses, and lakes and marshes in nearby depressions (31 Tomkovich, P. S. (1991). Three-year study of breeding Spoon-billed Sandpiper. Asian Wetland News 4:17. Close , 41 Syroechkovski, E. (2004). Brief notes on the Spoon-billed Sandpiper Calidris pygmeus Conservation Programme during summer 2004. BirdingASIA 2:68–69. Close ). The broods remain on the nesting territory for the first few days after hatching, and then move to lakeshores and wet meadows near the nest sites (42 Tomkovich, P. S. (1995). Breeding biology and breeding success of the Spoon-billed Sandpiper Eurynorhynchus pygmeus. Russian Journal of Ornithology 4: 77–91. Close ). There are two slightly different types of nesting habitat: (1) patches of moss-heath vegetation on the pebble spits that separate lagoons from the sea or form ancient ridges further inshore, and (2) lowland tundra alongside stream mouths; typical habitat is patchily vegetated with grasses (Elymus sp., Dupontia fisheri), crowberry (Empetrum nigrum), dwarf willows (Salix sp.), sedges, and mosses, and interspersed with shallow ponds, and on spring arrival the birds display where the ice is melting on sand-gravel spits and on the drier areas of lagoon shores near estuaries (43 Portenko, L. A. (1972). Birds of the Chukchi Peninsula and Wrangel Island. Volume 1. Delhi, India. [English translation 1981.] Close , 31 Tomkovich, P. S. (1991). Three-year study of breeding Spoon-billed Sandpiper. Asian Wetland News 4:17. Close , 44 Tomkovich, P.S. (1994). [Spatial structure of the Spoon-billed Sandpiper (Eurynorhynchus pygmeus) population at the breeding grounds]. Pp. 130–148 in: [Modern Ornithology 1992]. Nauka, Moscow. (In Russian with English summary.). Close ). This type of habitat is apparently a long-lasting successional stage of shoreline development, where the vegetation cover is thin and permafrost structures and thermokarst processes are poorly developed, and in winter such sites are wind affected and snow-carved, which favors earlier snow-melt.

In the nonbreeding range, the Gulf of Mottama in Myanmar is particularly significant, with surveys indicating that this area supports up to 60% of the global non-breeding population of the Spoon-billed Sandpiper during peak years. In this region, the birds are commonly observed foraging on mixed sand-mud substrates, which are rich in polychaetes, crabs, and insect larvae. They often select areas further from the main channels, where shallow surface puddles contain higher densities of prey (36 Aung, P. P., S. Moses, N. A. Clark, G. Q. A. Anderson, G. M. Hilton, G. M. Buchanan, C. Zöckler, and R. E. Green. (2020). Recent changes in the number of Spoon-billed Sandpipers Calidris pygmaea wintering on the Upper Gulf of Mottama in Myanmar. Oryx 54(1): 23–29. Close ). Similarly, Leizhou Bay in southern China is another key wintering site for the species. Surveys from 2019 to 2022 show that the bay’s shallow tidal pools, close to the seawall, provide optimal foraging conditions, making it a crucial habitat for wintering Spoon-billed Sandpiper (45 Lu, X., H. Yang, T. Piersma, L. Sun, Q. Chen, Y. Jia, G. Lei, L. Cheng, and X. Rao (2022). Food resources for Spoon-billed Sandpipers (Calidris pygmaea) in the mudflats of Leizhou Bay, southern China. Frontiers in Marine Science 9:1005327. Close ). Additionally, habitat models predict that coastal areas in China, including Leizhou Bay, will continue to be critical stopover and wintering sites as environmental pressures increase (46 Bradfer-Lawrence, T., A. E. Beresford, G. Q. A. Anderson, P. P. Aung, Q. Chang, S. U. Chowdhury, N. A. Clark, Y. N. Gerasimov, R. E. Green, G. M. Hilton, B. Hughes, E. G. Lappo, J. Li, E. E. Syroechkovskiy, P. S. Tomkovich, C. Zockler, and G. M. Buchanan (2021). Modelling the potential non-breeding distribution of Spoon-billed Sandpiper Calidris pygmaea. Bird Conservation International 31(2):169–184. Close ).

In Bangladesh, the Meghna Estuary serves as another important non-breeding site with counts of minimum 48 individuals in 2016 (47 Chowdhury, S. U., M. Foysal, M. A. A. Diyan, and S. Ahmed (2018). Discovery of an important wintering site of the Critically Endangered Spoon-billed Sandpiper Calidris pygmaea in the Meghna Estuary, Bangladesh. Bird Conservation International 28:251–262. Close ). These birds forage on the shallow mudflats in the region, showing clear preference for sandy intertidal mudflats with a thin layer of soft mud collecting in ripples, spending 98% of their time feeding within small pools left by the receding tide (48 Bird, J. P., A. C. Lees, S. U. Chowdhury, R. Martin, and E. Ul Haque (2010). A survey of the Critically Endangered Spoon-billed Sandpiper Eurynorhynchus pygmeus in Bangladesh and key future research and conservation recommendations. Forktail 26:1–8. Close ),although detailed studies on prey availability remain limited (47 Chowdhury, S. U., M. Foysal, M. A. A. Diyan, and S. Ahmed (2018). Discovery of an important wintering site of the Critically Endangered Spoon-billed Sandpiper Calidris pygmaea in the Meghna Estuary, Bangladesh. Bird Conservation International 28:251–262. Close ).

These mudflat ecosystems across Myanmar, southern China, and Bangladesh are essential to the survival of the species during the non-breeding season, and any loss or degradation of these habitats could have significant impacts on the global population (46 Bradfer-Lawrence, T., A. E. Beresford, G. Q. A. Anderson, P. P. Aung, Q. Chang, S. U. Chowdhury, N. A. Clark, Y. N. Gerasimov, R. E. Green, G. M. Hilton, B. Hughes, E. G. Lappo, J. Li, E. E. Syroechkovskiy, P. S. Tomkovich, C. Zockler, and G. M. Buchanan (2021). Modelling the potential non-breeding distribution of Spoon-billed Sandpiper Calidris pygmaea. Bird Conservation International 31(2):169–184. Close ).