SummaryThe Spoon-billed Sandpiper Eurynorhynchus pygmeus (IUCN Category: Critically Endangered) is in rapid decline. Data from across the entire breeding range (Chukotka and Koryakya in the Russian far north-east) and especially from the well-studied southern core breeding area at Meinypilgyno, confirm the continuing strong decline. At four breeding sites, where more than two counts were available for analysis, the decline was estimated at 26% per annum between 2002 and 2009, or an 88% decline over this period. Allowing for unsurveyed areas, this equates to a decline from a total population of approximately 1,000 breeding pairs in 2000 to 120-220 in 2009. Breeding studies at Meinypilgyno in 2003-2007 (not 2006) showed that the proportion of nests hatching at least one chick was 0.65 and once chicks left the nest, the mean brood size of chicks up to one week old was 1.99. Where it was possible to follow broods, 0.61 chicks fledged per nesting attempt. Survival and recruitment analysis of birds ringed at Meinypilgyno indicated that annual adult survival did not significantly differ over the 2003-2009 study but that recruitment in to the adult breeding population was effectively zero in all but one year of the study (2005). Resighting data for the last two years of the study were sparse due to very low numbers of marked adults being recorded and survival rates over the last 2-3 years of the study must therefore be treated with caution. The analysis therefore indicated that after fledging, survival during immaturity must be very low, leading to a low (or no) recruitment into an ageing population. Recent observations collated from the non-breeding areas confirm the declining trend observed in the breeding areas and imply that the main threats to the population lie along the migration route or in the wintering areas. These are poorly known although hunting in the wintering areas has been identified as a major mortality factor. Other threats include major loss of their intertidal habitats, and collection of birds on the breeding areas by specimen collectors. Improved monitoring in both the breeding and non-breeding areas as well as research on juvenile survival is recommended. Concerted international conservation action is essential if this species is to avoid extinction. This requires (i) improved understanding of the main wintering and staging areas and associated threats; (ii) addressing those threats that can be tackled with immediate effect, such as hunting; (iii) continued long-term monitoring on the breeding areas; (iv) an exploration of other potential breeding areas; (v) conservation action at all important stop-over and wintering sites along the entire flyway and (vi) consideration of a captive-breeding programme to ensure the survival of this species.
SummaryThe Yellow Sea region is of high global importance for waterbird populations, but recent systematic bird count data enabling identification of the most important sites are relatively sparse for some areas. Surveys of waterbirds at three sites on the coast of southern Jiangsu Province, China, in 2014 and 2015 produced peak counts of international importance for 24 species, including seven globally threatened and six Near Threatened species. The area is of particular global importance for the ‘Critically Endangered’ Spoon-billed Sandpiper Calidris pygmaea (peak count across all three study sites: 62 in spring [2015] and 225 in autumn [2014] and ‘Endangered’ Spotted Greenshank Tringa guttifer (peak count across all three study sites: 210 in spring [2014] and 1,110 in autumn [2015]). The southern Jiangsu coast is therefore currently the most important migratory stopover area in the world, in both spring and autumn, for both species. Several serious and acute threats to waterbirds were recorded at these study sites. Paramount is the threat of large-scale land claim which would completely destroy intertidal mudflats of critical importance to waterbirds. Degradation of intertidal mudflat habitats through the spread of invasive Spartina, and mortality of waterbirds by entrapment in nets or deliberate poisoning are also real and present serious threats here. Collisions with, and displacement by, wind turbines and other structures, and industrial chemical pollution may represent additional potential threats. We recommend the rapid establishment of effective protected areas for waterbirds in the study area, maintaining large areas of open intertidal mudflat, and the urgent removal of all serious threats currently faced by waterbirds here.
SummaryDeclines in populations of the Critically Endangered Spoon-billed Sandpiper Calidris pygmaeus have been rapid, with the breeding population now perhaps numbering fewer than 120 pairs. The reasons for this decline remain unresolved. Whilst there is evidence that hunting in wintering areas is an important factor, loss of suitable habitat on passage and wintering areas is also of concern. While some key sites for the species are already documented, many of their wintering locations are described here for the first time. Their wintering range primarily stretches from Bangladesh to China. Comprehensive surveys of potential Spoon-billed Sandpiper wintering sites from 2005 to 2013 showed a wide distribution with three key concentrations in Myanmar and Bangladesh, but also regular sites in China, Vietnam and Thailand. The identification of all important nonbreeding sites remains of high priority for the conservation of the species. Here, we present the results of field surveys of wintering Spoon-billed Sandpipers that took place in six countries between 2005 and 2013 and present species distribution models which map the potential wintering areas. These include known and currently unrecognised wintering locations. Our maximum entropy model did not identify any new extensive candidate areas within the winter distribution, suggesting that most key sites are already known, but it did identify small sites on the coast of eastern Bangladesh, western Myanmar, and the Guangxi and Guangdong regions of China that may merit further investigation. As no extensive areas of new potential habitat were identified, we suggest that the priorities for the conservation of this species are habitat protection in important wintering and passage areas and reducing hunting pressure on birds at these sites.
We studied reproductive success and post‐breeding movements of 32 adult female emperor geese Chen canagica that were marked with satellite radio transmitters on their nesting area on the Yukon‐Kuskokwim Delta (YKD), Alaska 2000–2004. All 16 females that failed to successfully reproduce departed the YKD and moulted remiges either on the north coast of the Chukotka Peninsula, Russia (n=15), or on St. Lawrence Island, Alaska (n=1). Of 16 females that successfully nested, one migrated to Russia following hatch whereas the remainder stayed on the YKD. While moulting on the Chukotka Peninsula, emperor geese with satellite transmitters primarily used coastal lagoons west of Kolyuchin Bay. We observed 21,150 adult‐plumaged emperor geese during aerial surveys in Chukotka in 2002. Most (95%) were in the same region used by geese that had been marked with satellite transmitters in Alaska. The number of emperor geese observed in Russia was comparable to our estimate of ≥20,000 adults that either do not nest or nest unsuccessfully each year on the YKD, suggesting that most nonproductive adults, or ≥28% of the adult population departs the YKD to moult elsewhere. The number of moult migrants may be substantially higher in years of poor reproductive success or if adult‐plumaged birds that are not of breeding age also leave the YKD. Moult migration of emperor geese between Alaska and Russia is likely substantially greater than previously believed. Russian moulting habitats are important to the North American population of emperor geese and events that affect survival of geese in Russia could impact population trends on the YKD. Protection of coastal lagoons on the north coast of Chukotka is warranted.
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