Justification of Red List Category
This species is classified as Near Threatened because, although it is quite widespread, it has a moderately small population overall and this is thought to be in decline, owing primarily to destruction of its wintering grounds (BirdLife International 2001). An even more rapid population decline may take place in the future owing to climate change.
The global population is estimated to number c.23,000 individuals (Bamford et al. in prep), while national population sizes have been estimated at < c.100 breeding pairs and < c.10,000 individuals on migration in China and c.100-10,000 breeding pairs and c.50-1,000 individuals on migration in Russia (Brazil 2009).
There are no data on population trends; however, the species is probably in decline owing to pollution and development on the wintering grounds. In the future, these declines may be intensified by habitat shifts on the breeding grounds, caused by global warming.
Limnodromus semipalmatus has a disjunct breeding range in the steppe regions that extend from west to east Siberia, Russia, and south into Mongolia and Heilongjiang in north-east China. It has been recorded as a non-breeding visitor to Japan, North Korea, South Korea, mainland China, Hong Kong (China), Taiwan (China), Kazakhstan, Uzbekistan, India, Bangladesh, Sri Lanka, Myanmar, Thailand, Vietnam, Philippines, Malaysia, Singapore, Brunei, Indonesia, Papua New Guinea, Australia and New Zealand. The population size is estimated at 23,000 individuals (Bamford et al. in prep). It is dependent on a rather small number of wetlands, notably the wintering sites at the Banyuasin Delta on Sumatra, where up to 13,000 were estimated in 1988 (BirdLife International 2001), and Ujung Pangkah in east Java.
Behaviour This species is migratory but its movements are not well known (del Hoyo et al. 1996). It breeds in small colonies of 6-20 pairs often with White-winged Terns Chlidonias leucopterus, and although the timing and location of breeding varies considerably depending on water levels, most females lay between late-May and early-June (Johnsgard 1981, del Hoyo et al. 1996). Neighbouring nests are spaced 4-350 m apart (del Hoyo et al. 1996). Birds arrive in the wintering grounds in September (del Hoyo et al. 1996), returning usually in April (del Hoyo et al. 1996), although some small groups remain in the wintering range during the boreal summer (del Hoyo et al. 1996). It is a gregarious species, that occurs in small flocks during migration (Johnsgard 1981). At other times it occurs in pairs or small groups, with larger flocks of over 100 individuals roosting or feeding together at favoured sites (del Hoyo et al. 1996). Habitat Breeding It breeds in extensive freshwater wetlands in the steppe and forest steppe zones. Suitable habitats include lake shores, river deltas, flooded meadows and grassy bogs along rivers with short grass and sedge vegetation (del Hoyo et al. 1996), and areas of bare mud (Johnsgard 1981). It is also found on the boggy shores of alkaline ponds (Johnsgard 1981), and has been observed in rice fields (del Hoyo et al. 1996). Non-breeding During the non-breeding season it occurs in sheltered coastal environments, primarily estuarine and intertidal mudflats, lagoons, creeks and saltworks (del Hoyo et al. 1996). It will also roost on sandy beaches or in shallow lagoons during this season (del Hoyo et al. 1996). Human modified landscape features such as salt-pans have also been shown to be important overwintering habitat (Sripanomyom et al. 2011). Diet Breeding On the breeding grounds its diet consists of small fish, insect larvae and oligochaetes (del Hoyo et al. 1996). Non-breeding On migration and in its wintering range, it feeds on polychaetes, insect larvae and molluscs (del Hoyo et al. 1996). Breeding site The nests of one colony were reported to be sited either on mounds among reeds in shallow water, or in the open, in hollows almost devoid of cover (Johnsgard 1981). On bare ground the nest is a shallow depression lined with grass (del Hoyo et al. 1996). Those found over water are created from grass stalks and dead leaves (Johnsgard 1981). They are sometimes found up to 8-12 cm above water that is 25 cm deep (del Hoyo et al. 1996).
It may be particularly vulnerable to habitat loss in its breeding grounds as a result of the drainage of wetlands for agriculture, or their drying-out as a result of climate change (del Hoyo et al. 1996). It may also be vulnerable to hunting, pollution and other pressures on both the breeding and wintering grounds. Wetland loss and degradation along its migration route is a potential threat, especially in the Yellow Sea where c.40% stage during northward migration (Barter 2002).
Conservation Actions Underway
CMS Appendix II.The species is included in the action plan for Australian Birds 2010 (Garnett et al. 2011).
Text account compilers
Benstead, P., Butchart, S., Derhé, M., Mahood, S., North, A.
BirdLife International (2019) Species factsheet: Limnodromus semipalmatus. Downloaded from http://www.birdlife.org on 16/01/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 16/01/2019.