First indications of a sharp population decline in the globally threatened Spoon-billed Sandpiper Eurynorhynchus pygmeus

Abstract

SummarySpoon-billed Sandpiper Eurynorhynchus pygmeus is classed as globally Vulnerable, based on the only available population estimate, made in 1977, of 2,000-2,800 pairs. Surveys for breeding Spoon-billed Sandpipers were carried out in summer 2000 on the Anadyr estuary coast, the Chukotka autonomous region, Russia. Although six new breeding sites were found, only 16-17 breeding males/pairs were recorded on the northern coast of the Anadyr estuary and five males/pairs on the southern coast and more southerly lagoons. These numbers were much lower than expected, and the species was not recorded in several apparently suitable areas. Four formerly known breeding sites held only one displaying male between them. At no site was there evidence of an increasing or stable local population. Together with other indicative data these suggest a sharp decline in the population of Spoon-billed Sandpiper. The previous population size estimate obviously requires updating, both because there were some incorrect assumptions in the calculations made for the first population estimate, and also due to a recent population decline. It is likely that the current population numbers under 1,000 breeding pairs. Given that the population of this species may be substantially lower than the only previous estimate, and the evidence for a possible rapid decline in its population described in this paper, it is recommended that its IUCN status is changed from Vulnerable to Endangered. No reasons for the apparent rapid rate of decline are evident within the breeding range. ''Bottle-necks'' should be looked for at migration sites or wintering grounds, but currently, monitoring of the population is only possible on the breeding grounds.

Greater shrub dominance alters breeding habitat and food resources for migratory songbirds in Alaskan arctic tundra

“…Our findings, integrated across the arctic foothills region of Alaska, indicate that: (i) Lapland longspurs and White‐crowned sparrows select distinct and nonoverlapping nest sites, with Lapland longspurs nesting only in E. vaginatum ‐dominated tussock tundra where shrub height does not exceed 20 cm, and White‐crowned sparrows nesting primarily under moderate height shrubs ranging from 20 cm to 1 m in height, regardless of shrub species; (ii) increasing shrub dominance in northern Alaska may be accompanied by a reduction in total arthropod biomass, but since flies are the primary food source for both nesting Lapland longspurs and White‐crowned sparrows and their nestlings, and they are more abundant in shrubs, the availability of their preferred food source may be enhanced; (iii) by 2050, we predict the expansion of shrub‐dominated communities and tree cover mosaic will result in a ~20–60% increase in White‐crowned sparrow nesting habitat extent, and a decline of ~20–60% in Lapland longspur nesting habitat, suggesting that habitat for songbird species with similar nesting preferences will change in a similar manner; (iv) there is a mismatch between the resolution of existing vegetation models and the scale of habitat characteristics that are important to songbirds which enables only first approximations of their future habitat extents, and this limitation likely extends to other wildlife. Our study thus complements and broadens current understanding of how changing tundra vegetation cover will impact arctic breeding birds since the majority of research in this field has focused on migratory waterbirds whose arctic breeding habitat extent is predicted to shrink by 25–85% over the current century (Zöckler, ; Zöckler & Lysenko, ; Tomkovich et al ., ).…”

Rapid and continued population decline in the Spoon-billed Sandpiper Eurynorhynchus pygmeus indicates imminent extinction unless conservation action is taken

“…Given the nature of the terrain, fledgling success was even more difficult to estimate but from behaviour of the adults and observation of juvenile birds, fledgling success of broods was estimated at 50% of the mean observed brood size in 2003, 2004 and 2007 and 40% in 2005. For further details on breeding survey techniques see Tomkovich and Soloviev (2000), Tomkovich et al (2002) and Syroechkovskiy (2005).…”

Discovery of an important wintering site of the Critically Endangered Spoon-billed Sandpiper Calidris pygmaea in the Meghna Estuary, Bangladesh

“…The species breeds in the Russian Arctic, primarily on the coast of the Chukotsk Peninsula (e.g. Flint and Kondratiev 1977, Tomkovich et al 2002) and winters mainly in the intertidal habitats of Bangladesh, Myanmar, Vietnam, southern China and the inner Gulf of Thailand (Zöckler et al 2010b, BirdLife International 2016, Bird et al 2010, Chowdhury et al 2011, Zöckler et al 2016). Between 2002 and 2009 numbers at monitored breeding sites declined by about 26% per year (Zöckler et al 2010a).…”