White-rumped sandpipers are very rare vagrants to New Zealand, with only two accepted records. They breed exclusively in North America, before departing for non-breeding grounds in South America from below the Tropic of Capricorn to the bottom of Tierra del Fuego. Here they are often associated with the very similar Baird’s sandpiper, another rare New Zealand visitor, with which they are sometimes considered as a ‘species pair’, though their biology differs in a number of respects.
White-rumped sandpipers are small sandpipers that are between a red-necked stint and a sharp-tailed sandpiper in size. In non-breeding plumage they are plain grey or greyish-brown on the upperparts, with the centre of the feathers darker than the rest and a variable pale fringe at the extremities. It most closely resembles Baird’s sandpiper, which it differs from in having (usually) diffuse streaking along the flanks, which Baird’s does not, and a more prominent pale supercilium. The bill is blackish, but with close views has a dull reddish cast to the base of the lower mandible. The legs are black. The diagnostic white rump (actually its upper tail) shows as a broad band across the entire tail, similar to a curlew sandpiper, and eliminating the very similar Baird’s sandpiper.
Voice: the typical flight call is a very high-pitched sharp ‘zeet’, recalling an insect or a mouse.
Similar species: Baird’s sandpiper is similar size, shape and colouration, but is more elongate, does not have streaking on its white flanks, and has a broad dark centre to the rump. Red-necked stint, western sandpiper, and semipalmated sandpiper are all smaller with a thin dark strip down the rump, with white each side.
Distribution and habitat
White-rumped sandpipers breed in North America’s high Arctic, from Alaska to north-west Greenland, with a few birds in the Russian Far East (including Wrangel Island and the Chukotski Peninsula). Migration routes tend to follow inland paths northbound, and they are rare west of the Rockies. The southbound migration more closely follows the Atlantic coast. Non-breeding grounds are in southern South America, from Ecuador, Paraguay, Uruguay and southern Brazil to Tierra del Fuego, and from sea level to 4,000 m in the Chilean Andes. Flocks are regular in the Falkland Islands, and vagrants have occurred in South Georgia, Europe, and other locations as far afield as South Africa. White-rumped sandpipers have been identified over 20 times in Australia. There are two accepted New Zealand records.
The North American (including Canadian) population of white-rumped sandpipers is estimated at 300,000 birds. There are two accepted New Zealand records.
New Zealand records
Only two accepted records for New Zealand: two birds at Manukau Harbour in December 1969; one at Parengarenga Harbour in March 1971.
Behaviour and ecology
White-rumped sandpipers migrate rather later than other species through the Americas, favouring inland sites, to the east of the Rocky Mountains, when moving north, and sometimes persisting into late autumn before moving to their non-breeding grounds again. Southbound migration through North America is typically further east. While favouring freshwater habitats, non-breeding (and some migrant) birds may often be found on the coast. The two New Zealand records were in estuarine habitats. White-rumped sandpipers breed on damp, mainly near-coastal tundra. The high-pitched short squeaky call ‘zeet’ likely to be given on take-off is distinctive.
Threats and conservation
White-rumped sandpipers are ranked Least concern by IUCN, as the birds are numerous (300,000+ individuals) and cover a wide geographical range. Monitoring at two breeding sites showed no change in density over a 20-year period..
White-rumped sandpipers breed as monogamous pairs in wet, mostly coastal tundra. Incubation of the 4-egg clutch is shared and takes 20-22 days. The chicks leave the nest and feed themselves soon after hatching. Most brood care is by the male; chicks can fly from 18 days old.
White-rumped sandpipers consume small invertebrates obtained by rapid pecking action on muddy surfaces, or sometimes in short grassland
Edgar, A.T, 1971. Sightings of rare waders in the Far North. Notornis 18: 116-117.
Hayman, P.; Marchant, J.; Prater, T. 1986. Shorebirds: an identification guide to the waders of the world. Croom Helm, London.
McKenzie, H.R. 1970. A new arctic wader for New Zealand: two white-rumped (Bonaparte’s) sandpipers at Karaka. Notornis 17: 236-237.
Medway, D.G. 2010. Charadriiformes (waders). Pp. 191-223. In: Checklist Committee (OSNZ) 2010. Checklist of the birds of New Zealand, Norfolk and Macquarie Islands, and the Ross Dependency, Antarctica (4th edn). Ornithological Society of New Zealand & Te Papa Press, Wellington.
Miskelly, C.M.; Scofield, P.R.; Sagar, P.M.; Tennyson A.J.D.; Bell, B.D.; Bell, E. A. 2011. Vagrant and extra-limital bird records accepted by the OSNZ Records Appraisal Committee 2008-2010. Notornis. 58(2), 64-70
Moskoff, W.; Montgomerie, R. 2002. Baird's Sandpiper (Calidris bairdii), The birds of North America online (A. Poole, ed.). Ithaca: Cornell Lab of Ornithology; Retrieved from the Birds of North America Online: http://bna.birds.cornell.edu/bna/species/661 doi:10.2173/bna.661 Viewed 12 May 2013.
O’Brien, M.; Crossley, R.; Karlson, K., 2006. The shorebird guide. Houghton Mifflin, Boston.
Paulson, D. 1993. Shorebirds of the Pacific Northwest. UBC Press, Vancouver.
Crocker, T.C. 2013. White-rumped sandpiper. In Miskelly, C.M. (ed.) New Zealand Birds Online. www.nzbirdsonline.org.nz
- Breeding season
- Egg laying dates