Spoon-billed Sandpiper
Scientific Name:(Eurynorhynchus pygmeus)
This charismatic species is listed as Critically Endangered because it has an extremely small population that is undergoing an extremely rapid population reduction. This is because of a number of factors, including habitat loss in its breeding, passage and wintering grounds, that are compounded by disturbance, hunting and the effects of climate change. Fledging success and juvenile recruitment are very low, leading to fears that the population is ageing rapidly; action is now urgently required to prevent the extinction of this species.
Identification
14-16 cm. Small stint with spatulate bill. Breeding adult has red-brown head, neck and breast with dark brown streaks. Blackish upperparts with buff and pale rufous fringing. Non-breeding adult lacks reddish coloration, but has pale brownish-grey upperparts with whitish fringing to wing-coverts. White underparts.
Similar spp. Red-necked Stint
C. ruficollis and Little Stint
C. minuta lack spatulate bill. Non-breeders of both species have less white on forehead, appear smaller-headed and have narrower supercilia. Breeding
C. ruficollis has less uniformly fringed rufous/brick-red fringes to scapulars.
VoiceQuiet, rolling
preep and shrill
wheet, usually in flight.
Distribution and population
This species has a naturally limited breeding range on the Chukotsk peninsula and southwards up to the isthmus of the Kamchatka peninsula, in north-eastern Russia (BirdLife International 2001). It migrates down the western Pacific coast through Russia, Japan, North Korea, South Korea, mainland China, Hong Kong(China), Taiwan (China) and Vietnam,to its main wintering grounds inBangladesh and Myanmar. Wintering birds have also been recorded fromIndia, Sri Lanka, Thailand, Vietnam, the Philippines, in the Fujian province of China (F. Cheung in litt. 2010), Peninsular Malaysia and Singapore. It occurs regularly at only a few sites within this wintering range, with important countries including Bangladesh and Thailand, and Myanmar, which is potentially the most important wintering country (with 84 recorded in 2007-2008, 73 in January 2009 (Clark 2009), and 89 in 2010 (Zöckler et al. 2010b); 150-220 were estimated in the Bay of Martaban in 2010 (Zöckler et al. 2010a,b). In March-April 2010, a minimum total of 49 individuals were recorded during targeted surveys along the coast of Bangladesh (Bird et al. 2010). A count of up to 103 individuals at Rudong, China, in October 2011 is likely to have accounted for a substantial proportion of the global population (Menxiu Tong in litt. 2011). Due to its specialised breeding habitat requirements it was probably always a scarce species, but numbers have dropped in recent years and surveys on the breeding grounds have revealed a dramatic decline from 2,000-2,800 pairs in the 1970s to fewer than 1,000 pairs in 2000, 402-572 pairs in 2003, 350-380 pairs in 2005 (Zöckler and Bunting 2006) and not more than 150-320 pairs in 2008 (Zöckler and Syroechkovskiy in prep.). The breeding population in 2009-2010 was optimistically estimated at 120-200 pairs (Bird et al. 2010, Zöckler et al. 2010a) (in an estimated total population of 500-800 individuals [Zöckler et al. 2010a]), perhaps indicating an 88% decline since 2002, equating to an annual rate of decline of 26% (Zöckleret al. 2010a). These declines have taken place across all known breeding sites, and it is unlikely that significant colonies remain undiscovered (Zöckler 2005, Zöckler and Bunting 2006). Declines are also being observed at wintering grounds. For example, no birds were sighted wintering in Vietnam in 2009 at a site that supported at least 27 birds in the mid 1990s (E. Syroechkovskiy et al. in litt. 2009). Breeding success is very low: average productivity was 0.66 young fledged per nest in 2005, and much lower in 2007, and this is compounded by a very low rate of juveniles and adults returning to the breeding grounds. The species now has an ageing and rapidly declining population with little recruitment. For example, data collected on birds at one breeding area from 2003 to 2009 suggest that recruitment into the adult breeding population was effectively zero in all years apart from 2005 and 2007 (Zöckler et al. 2010a). Evidence to support suspicions that immature birds stay on their wintering grounds until their second year came from photographs of a second calendar-year bird in Thailand in July 2010 (G. Chutima in litt. 2010).
Population justification
The breeding population in 2009/2010 was estimated at 120-200 pairs, roughly equivalent to 240-400 mature individuals and 360-600 individuals in total, although this is thought to be an optimistic estimate.
Trend justification
The breeding population in 2009/2010 was optimistically estimated at 120-200 pairs. An estimate of 120-200 pairs indicates an 88% decline since 2002, equating to an annual rate of decline of 26%
Ecology
It has a very specialised breeding habitat, using only lagoon spits with crowberry-lichen vegetation or dwarf birch and willow sedges, together with adjacent estuary or mudflat habitats that are used as feeding sites by adults during nesting. The species has never been recorded breeding further than 5 km (and exceptionally once, 7 km) from the sea shore. Breeding birds are very site faithful. It breeds either in single pairs or loose aggregations. During winter it prefers mixed sandy tidal mudflats with uneven surface and very shallow water, mainly in the outermost parts of river deltas and outer islands, often with a higher sand content and thin mud layer on top. In the areas with total coastal conversion it favours certain stages in the management of saltpans. The species feeds by plover-style pecking and occasionally probing, also appearing to use its bill as a shovel.
Threats
Throughout its migratory and wintering ranges, tidal flats are being reclaimed for industry, infrastructure and aquaculture and are becoming increasingly polluted. The important staging area at Saemangeum and Geum estuary, South Korea, including the Mangyeung and Tongjin estuaries, has already been reclaimed, and remaining wetlands are under serious threat of reclamation in the near future (Zöckler and Bunting 2006). Another important passage site, with up to 20 birds, is Rudong (China), which has been negatively affected by an introduced grass and is ear-marked for reclamation in the near future (P. Morris in litt. 2010) as well as being the site for development of the largest wind farm in Asia (C. Zöckler in litt. 2007, 2009, 2010). Plans for a deep-water port at Sonadia and cross-dams along the coast of Bangladesh continue to pose threats (Bird et al. 2010). Although not specifically targeted, it is regularly caught in nets set to catch other waders for food in the key wintering areas of Bangladesh and Myanmar (C. Zöckler in litt. 2007, 2009, 2010; Zöckler and Thin Hla 2009; Bird et al. 2010; Zöckler et al. 2010b), and this may be a particularly serious threat to birds wintering on Nan Thar Island and in the Gulf of Martaban, Myanmar (C. Zöckler in litt. 2007, 2009, 2010; Zöckler et al. 2010b). A survey of hunting activities in five villages around Sonadia Island, Bangladesh, in September 2010, found that of the 53 hunters interviewed, eight of them claimed to have caught a total of 22 Spoon-billed Sandpipers between October 2009 and April 2010 (Chowdhury 2010). Hunting in the species's non-breeding range could be a crucial factor in the poor rate of recruitment into the breeding population, as immature birds do not return to the breeding areas until they are two years old and thus are more exposed to capture (Zöckler et al. 2010a). There are no immediate threats to the breeding grounds, but nests in the vicinity of villages are sometimes destroyed by dogs (E. Syroechkovskiy in litt. 2007). Poor breeding productivity in recent years has been attributed to heavy nest predation and bad weather (Syroechkovskiy et al. 2009). Significant habitat degradation has been observed in 5 of 30 visited breeding locations (C. Zöckler in litt. 2007, 2009, 2010). Human disturbance, both by residents and researchers, may cause increased levels of nest desertion and predation by foxes and skuas (Zöckler and Bunting 2006). Shorebirds, including this species, are also occasionally killed by children with slingshots (Zöckler and Bunting 2006); one male was also shot by a Russian hunter near the Chinese border in 2008 (Zöckler and Syroechkovskiy 2008). Small but significant numbers of birds and their eggs have been collected for scientific purposes in the last 20 years, with one small colony completely wiped out due to this activity (Zöckler and Bunting 2006). Climate change and associated habitat shifts are expected to impact negatively on this species and others dependent on tundra habitat for breeding. Modelling indicates that 57% of the breeding habitat for this species could be lost by 2070 (Zöckler and Lysenko 2000).
Conservation actions underway
CMS Appendix I and II. Protected areas in its breeding, staging and wintering areas include Moroshechnaya and several local wildlife refuges on the Chukotsk peninsula (Russia), Yancheng and Chongming Dongtan (China), Mai Po (Hong Kong), Lanyang estuary (Taiwan), Point Calimere and Chilka lake (India), and Xuan Thuy Nature Reserve (Vietnam). The Bird Conservation Society of Thailand have lobbied the Government of Thailand to request that Khok Kham be designated a Ramsar site (Fowlie 2011). Annual surveys are undertaken of breeding sites on Chukotka and over 450 adults and young have been ringed on the breeding grounds since 2000 (Zöckler et al. 2008). In June-July 2011, dedicated surveys for breeding Spoon-billed Sandpipers were due to be conducted in the previously inaccessible Olyutorskiy Bay (Fowlie 2011). Local support groups have been established in some breeding areas and negotiations have taken place to reduce short-term hunting pressure at one of the key wintering sites in Myanmar (Zöckler and Thin Hla 2009; Zöckler et al. 2010b). Researchers and a local environmentalist group convinced two villages on Nan Thar Island to agree to a hunting ban of the species, with a view to develop an ecologically and economically sound alternative in the future (C. Zöckler in litt. 2007, 2009, 2010; Zöckler et al. 2010b). In the Bay of Martaban, socio-economic surveys carried out in early 2010 indicated that bird-hunting is undesirable and that most hunters would readily switch to alternative livelihoods if assisted (BANCA 2010). These surveys were swiftly followed by mitigation activities in the same year, in which hunters agreed to stop their activities in exchange for equipment to provide them with an alternative income source and awareness-raising events and materials were provided for whole communities (BANCA in litt. 2010). In 2011, awareness-raising and advocacy activities were planned for schools in China. A Species Action Plan was produced in 2006, and updated in 2008 and 2010 . At the fifth meeting of the East Asian-Australasian Flyway Partnership in Cambodia in December 2010, the partners agreed to establish a Task Force for this species, charged with implementing the action plan (Fowlie 2011). Studies into the feasibility of captive breeding and use of data-loggers on small calidrine waders were on-going in 2009. A captive-rearing and breeding programme started in 2011, when eggs were collected in Chukotka and the young birds were subsequently transported to purpose-built conservation breeding facilities at the Wildfowl and Wetlands Trust headquarters at Slimbridge, UK (Pain 2010, sbsproject.wordpress.com).
Conservation actions proposed
Continue to monitor numbers at known breeding sites and carry out searches of suitable habitat in North Kamchatka. Actively prevent collection of eggs and birds for scientific purposes, museums and private collections. Take measures to ensure that researcher activity does not increase mortality. Ensure effective legal protection of all known breeding sites. Survey existing and potential wintering sites in Myanmar and Bangladesh. Stop hunting and trapping at key sites in Myanmar, Bangladesh and Russia. Ensure protection of newly discovered sites and existing sites, especially in South Korea. Campaign against the continued reclamation of intertidal mudflats along the entire migration route. Restore reclaimed wetland sites. Legally protect it in all range states. Identify and mitigate pressures at breeding grounds. Lobby against plans for a deep-water port at Sonadia, Bangladesh (Bird et al. 2010). Pursue protected area status for the Bay of Martaban and other coastal sites in Myanmar (BANCA in litt. 2010).
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