Justification of Red List Category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.
The global population is estimated to number > c.180,000 individuals (Wetlands International 2006), while the population in Russia has been estimated at c.100-100,000 breeding pairs and c.50-10,000 individuals on migration (Brazil 2009).
Although Wetlands International consider the current population trend to be unknown, it is suspected to be stable in the absence of evidence for any declines or substantial threats (del Hoyo et al. 1996).
Behaviour This species is strongly migratory, travelling from mid-August to October along the coast of eastern Asia on a narrow front with few stop-overs (del Hoyo et al. 1996). On its wintering grounds in Australia the species also makes erratic movements in relation to ranifall (del Hoyo et al. 1996). It breeds from late-May to early-August in loose colonies (del Hoyo et al. 1996) of 3-30 pairs (Labutin et al. 1982) and migrates in flocks of up to 1,000 individuals (del Hoyo et al. 1996). During the non-breeding season it occurs in dense flocks of several hundreds or thousands of individuals and gathers in large flocks to roost during the warmest part of the day and at night (del Hoyo et al. 1996). Habitat Breeding The species breeds in secondary vegetation growth in open burnt areas or in grassy clearings in northern montane larch Larix spp. or dwarf birch woodland, chiefly along river valleys (Hayman et al. 1986, del Hoyo et al. 1996) or on well-drained (Labutin et al. 1982) southward-facing mountain slopes (Flint et al. 1984). Non-breeding On passage the species shows a preference for foraging and resting in swampy meadows near lakes and along river valleys (Flint et al. 1984). It overwinters on dry inland grassland, bare cultivation (del Hoyo et al. 1996), dry mudflats and coastal plains of black soil (Johnsgard 1981) with scattered shallow pools of freshwater (Higgins and Davies 1996), swamps, lakes or flooded ground (del Hoyo et al. 1996). It shows a preference for short grass swards of less than 20 cm tall, and occasionally occurs in dry saltmarshes, coastal swamps, mudflats or sandflats in estuaries, or on the beaches of sheltered coasts (Higgins and Davies 1996). Diet Its diet consists predominantly of adult and larval insects (del Hoyo et al. 1996) (e.g. grasshoppers, crickets, weevils, beetles, caterpillars, ants (del Hoyo et al. 1996) and termites (Bellio et al. 2006)) and spiders as well as vegetable matter including seeds, rice husks and berries (del Hoyo et al. 1996). Breeding site The nest is a shallow depression located on open ground (del Hoyo et al. 1996) in open burnt areas or grassy clearings in larch Larix spp. or dwarf birch woodland, chiefly along river valleys (Hayman et al. 1986, del Hoyo et al. 1996). The species nests in loose colonies (del Hoyo et al. 1996) with neighbouring nests spaced between 200 and 300 m apart within a radius of 1 km (Labutin et al. 1982).
Important migratory stop-over sites for this species in northern Australia are being degraded through colonisation by invasive plants (e.g. Mimosa pigra, Hymenachne amplexicaulis and para grass Brachiaria mutica), saltwater intrusion as a result of rising sea-levels, and damage from feral pigs and buffalo (Bellio et al. 2006). The habitats of this species are also potentially threatened by agricultural intensification and pesticide contamination (del Hoyo et al. 1996).
Text account compilers
Ekstrom, J., Butchart, S., Malpas, L.
BirdLife International (2021) Species factsheet: Numenius minutus. Downloaded from http://www.birdlife.org on 08/12/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 08/12/2021.