CR
Spoon-billed Sandpiper Calidris pygmaea



Taxonomy

Taxonomic note
Calidris pygmaea (del Hoyo and Collar 2014) was previously placed in the genus Eurynorhynchus as E. pygmeus.

Taxonomic source(s)
del Hoyo, J., Collar, N.J., Christie, D.A., Elliott, A. and Fishpool, L.D.C. 2014. HBW and BirdLife International Illustrated Checklist of the Birds of the World. Volume 1: Non-passerines. Lynx Edicions BirdLife International, Barcelona, Spain and Cambridge, UK.
Mayr, E. 1933. Birds collected during the Whitney South Sea Expedition. XXVII. Notes on the variation of immature and adult plumages in birds and a physiological explanation of abnormal plumages. American Museum Novitates 666: 1-10.

IUCN Red List criteria met and history
Red List criteria met
Critically Endangered Endangered Vulnerable
A2abcd; C1+2a(ii) A2abcd+3bcd+4abcd; C1+2a(i,ii); D A2abcd+3bcd+4abcd; C1+2a(i,ii); D1

Red List history
Year Category Criteria
2021 Critically Endangered A2abcd; C1+2a(ii)
2018 Critically Endangered A2abcd+3bcd+4abcd; C2a(i)
2016 Critically Endangered A2abcd+3bcd+4abcd; C2a(i)
2015 Critically Endangered A2abcd+3bcd+4abcd; C2a(i)
2013 Critically Endangered A2abcd+3bcd+4abcd; C2a(i)
2012 Critically Endangered A2abcd+3bcd+4abcd;C2a(i)
2011 Critically Endangered A2a,b,c,d; A3b,c,d; A4a,b,c,d; C2a(i)
2010 Critically Endangered A2a,b,c,d; A3b,c,d; A4a,b,c,d
2009 Critically Endangered A2a,b,c,d; A3b,c,d; A4a,b,c,d
2008 Critically Endangered
2004 Endangered
2000 Vulnerable
1996 Vulnerable
1994 Vulnerable
1988 Threatened
Species attributes

Migratory status full migrant Forest dependency does not normally occur in forest
Land-mass type continent
Average mass -
Range

Estimate Data quality
Extent of Occurrence (breeding/resident) 355,000 km2 medium
Extent of Occurrence (non-breeding) 3,430,000 km2 medium
Severely fragmented? no -
Population
Estimate Data quality Derivation Year of estimate
Population size 240-620,490 mature individuals medium estimated 2021
Population trend decreasing good estimated 2009-2023
Rate of change over the past 10 years/3 generations (longer of the two periods) 70-80% - - -
Rate of change over the future 10 years/3 generations (longer of the two periods) 60-70% - - -
Rate of change over the past & future 10 years/3 generations (longer of the two periods) 68-72% - - -
Generation length 4.49 years - - -
Number of subpopulations 1 - - -
Percentage of mature individuals in largest subpopulation 100% - - -

Population justification: A total of ten repeats of a Lincoln-Peterson method to estimate the global population have resulted in a weighted mean single global estimate of 490 mature individuals (95% confidence limits 360-620) for the six-year period between 2014-2019 (Green et al. 2021). However, the most recent winter counts suggest a total number of birds in the order of 330-340 individuals (Zöckler et al. 2021), indicating that the total of mature individuals may actually already have fallen below 250 if we assume fewer than three-quarters of these are mature individuals. As such the population is placed within a custom band of 240-620 mature individuals, with a best single value of 490 (Green et al. 2021) but noting that this figure may already be outdated.

The trend of these estimates, albeit over a short-time frame, was a mean rate of reduction of 8% (Green et al. 2021), similar to the 9% estimated from surveys of the most important wintering population in Myanmar (Zöckler et al. 2010a). However, the confidence interval of the more recent trend estimates overlapped zero, such that there is low confidence in the accuracy of the trend magnitude. In the absence of better information, and noting the congruence with the rate of reduction estimated from wintering surveys, this rate of decline is taken to be the best estimate for the population as a whole for the current timeframe. This rate of reduction is equivalent (using an exponential model of decline) to a three-generation reduction of 68% (over 13.4 years), estimated as a rate of continuing decline of 31.5% in one generation (4.5 years) and 52.7% in two generations (9 years). However, prior to 2009 the rate of population reduction, based on counts of breeding pairs at surveyed locations, was reported to be extremely rapid at an annual rate of 26% between 2002-2008 (Zöckler et al. 2010a). As such, the past rate of reduction for the most recent three-generation period (2007-2021) is suspected to have been at a higher rate, and, given the uncertainty, is placed in a band of 70-80%.

Trend justification: Observations from the breeding areas in the first decade of the 2000s indicated an extremely rapid population reduction was taking place, with the annual rate of decline reported as 26% between 2002-2008 (Zöckler et al. 2010a). The rate of decline has slowed and, based surveys of the most important wintering area in Myanmar, annual rates of decline between 2009-2016 have been estimated at 9% (Aung et al. 2020). The most recent estimate of the rate of reduction is an 8% annual reduction, based on the ten repeats of the methodology to estimate the global population size between 2014-2019 (Green et al. 2021). The reduction in the rate of reduction is thought likely due to the impact of intensive conservation efforts (C. Zöckler in litt. 2019, Green et al. 2021), however the population is still estimated to be declining at a very rapid rate, and over the past three generations the reduction is still suspected to have been 70-80%.


Country/territory distribution
Country/Territory Presence Origin Resident Breeding visitor Non-breeding visitor Passage migrant
Bangladesh extant native yes
Cambodia extant vagrant
Canada extant vagrant yes
China (mainland) extant native yes yes
Hong Kong (China) extant native yes
India extant native yes
Indonesia extant vagrant yes
Japan extant native yes
Malaysia extant native yes
Myanmar extant native yes
North Korea extant native yes
Philippines extant vagrant yes
Russia extant native yes yes
Russia (Asian) extant native yes yes
Singapore extant vagrant yes
South Korea extant native yes
Sri Lanka extant native yes
Taiwan, China extant native yes
Thailand extant native yes
USA extant vagrant yes yes
Vietnam extant native yes yes

Important Bird and Biodiversity Areas (IBA)
Country/Territory IBA Name
Bangladesh Ganges-Brahmaputra-Meghna delta
Bangladesh Patenga Beach
Bangladesh Sonadia Island
Bangladesh Sunderbans (East, South, West Wildlife Sanctuaries)
China (mainland) Chongming Dongtan Nature Reserve
China (mainland) Dongting Hu wetlands
China (mainland) Min Jiang Estuary
Hong Kong (China) Inner Deep Bay and Shenzhen River catchment area
India Deepor Beel Bird Sanctuary
India Nalabana Bird Sanctuary (Chilika Lake)
India Point Calimere Wildlife Sanctuary
India Sundarbans Biosphere Reserve (National Park)
Malaysia North-central Selangor coast
Myanmar Ayeyarwady Delta (including Meinmahla Kyun)
Myanmar Gulf of Mottama
Myanmar Nantha Island
North Korea Daedong Bay
North Korea Kangryong field
Russia (Asian) Amur river mouth
Russia (Asian) Aniva bay
Russia (Asian) Getlyangen lagoon and Khalyustkin cape
Russia (Asian) Kievka and Chernaya river basins
Russia (Asian) Kuril islands (between Urup and Paramushir)
Russia (Asian) Lesser Kuril Ridge and Kunashir Island
Russia (Asian) Lower Anadyr lowlands
Russia (Asian) Lower Tumen river
Russia (Asian) Mechigmenskiy Gulf
Russia (Asian) Meinypylginski and Kapylgyn lakes
Russia (Asian) Nevskoye Lake
Russia (Asian) Nikolaya bay
Russia (Asian) North-east Sakhalin lagoons
Russia (Asian) Ola lagoon
Russia (Asian) Schast'ya Gulf
Russia (Asian) Shantarskiye Islands
Russia (Asian) Tyk and Viakhtu bays
Russia (Asian) Ul'banskiy bay
Russia (Asian) Vankarem lowlands and Kolyuchin bay
South Korea Dongjin estuary
South Korea Mangyeong estuary
South Korea Nakdong-gang estuary
South Korea Namyang Bay
South Korea Tidal flat area of southern Ganghwa-do island
Taiwan, China Chihben Wetlands
Thailand Inner Gulf of Thailand
Vietnam Ba Tri
Vietnam Nghia Hung
Vietnam Thai Thuy
Vietnam Xuan Thuy

Habitats & altitude
Habitat (level 1) Habitat (level 2) Importance Occurrence
Artificial/Aquatic & Marine Artificial/Aquatic - Salt Exploitation Sites suitable non-breeding
Grassland Tundra major breeding
Marine Intertidal Mud Flats and Salt Flats major non-breeding
Marine Intertidal Sandy Shoreline and/or Beaches, Sand Bars, Spits, Etc major breeding
Altitude 0 - 70 m Occasional altitudinal limits  

Threats & impact
Threat (level 1) Threat (level 2) Impact and Stresses
Agriculture & aquaculture Marine & freshwater aquaculture - Scale Unknown/Unrecorded Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Ecosystem degradation, Ecosystem conversion
Biological resource use Hunting & trapping terrestrial animals - Intentional use (species is the target) Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species mortality
Climate change & severe weather Habitat shifting & alteration Timing Scope Severity Impact
Future Whole (>90%) Slow, Significant Declines Low Impact: 5
Stresses
Indirect ecosystem effects, Ecosystem degradation, Reduced reproductive success
Energy production & mining Renewable energy Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Species mortality
Human intrusions & disturbance Work & other activities Timing Scope Severity Impact
Ongoing Majority (50-90%) Rapid Declines Medium Impact: 7
Stresses
Species disturbance, Reduced reproductive success
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Canis familiaris Timing Scope Severity Impact
Ongoing Minority (<50%) Rapid Declines Medium Impact: 6
Stresses
Reduced reproductive success, Species mortality
Invasive and other problematic species, genes & diseases Invasive non-native/alien species/diseases - Spartina alterniflora Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation
Pollution Garbage & solid waste Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem degradation
Pollution Industrial & military effluents - Oil spills Timing Scope Severity Impact
Ongoing Minority (<50%) Slow, Significant Declines Low Impact: 5
Stresses
Species mortality
Residential & commercial development Commercial & industrial areas Timing Scope Severity Impact
Ongoing Majority (50-90%) Very Rapid Declines High Impact: 8
Stresses
Ecosystem degradation, Ecosystem conversion
Residential & commercial development Tourism & recreation areas Timing Scope Severity Impact
Ongoing Minority (<50%) Unknown Unknown
Stresses
Ecosystem conversion

Utilisation
Purpose Scale
Food - human subsistence, national

Recommended citation
BirdLife International (2024) Species factsheet: Spoon-billed Sandpiper Calidris pygmaea. Downloaded from https://datazone.birdlife.org/species/factsheet/spoon-billed-sandpiper-calidris-pygmaea on 22/12/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from https://datazone.birdlife.org/species/search on 22/12/2024.