Calidris
Genus of birds
From Wikipedia, the free encyclopedia
Calidris is a genus of Arctic-breeding, strongly migratory wading birds in the family Scolopacidae. These birds form huge mixed flocks on coasts and estuaries in winter. They are small to medium-sized sandpipers, long-winged and relatively short-billed; some are difficult to identify because of the similarity between species, and various breeding, non-breeding, juvenile, and moulting plumages. With a few exceptions, they have a fairly stereotypical colour pattern, being brownish above and lighter, usually white or buffy coloured, on much of the underside. They often have a lighter supercilium above brownish cheeks.[2] The species are variously known in English as sandpipers or (particularly the smaller species) stints; some have their own unique names, with dunlin (a mediaeval name meaning "[small] brown bird"), knot (imitative of its call), ruff (named after its male display plumage), and sanderling and surfbird (named after their habitat and behaviour).[3] In North America, the smaller species are often known colloquially as peeps.
| Calidris | |
|---|---|
| Red knot (Calidris canutus) in juvenile plumage, Brittany, France | |
| Scientific classification | |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Aves |
| Order: | Charadriiformes |
| Family: | Scolopacidae |
| Genus: | Calidris Merrem, 1804 |
| Type species | |
| Tringa calidris[1] = Tringa canutus Gmelin, 1789 | |
| Synonyms | |
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Their bills are flexible, able to exhibit rhynchokinesis,[4] and have sensitive tips which contain numerous corpuscles of Herbst. This enables the birds to locate buried prey items, which they typically seek with restless running and probing.[5] Migratory shorebirds are shown to have declined in reproductive traits because of temporal changes of their breeding seasons.[6]
Taxonomy



The genus Calidris was introduced in 1804 by the German naturalist Blasius Merrem with the red knot as the type species.[7][8] The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for an unidentified grey-coloured waterside bird.[9]
Many of the species have been treated under other generic names at various times in the past, but these treatments leave Calidris polyphyletic;[10][11][12] synonyms are in brackets in the list below.
The genus contain 24 species:[13]
- Red knot Calidris canutus
- Great knot Calidris tenuirostris
- Surfbird Calidris virgata (syn. Aphriza virgata)
- Ruff Calidris pugnax (syn. Philomachus pugnax)
- Sharp-tailed sandpiper Calidris acuminata
- Broad-billed sandpiper Calidris falcinellus (syn. Limicola falcinellus)
- Curlew sandpiper Calidris ferruginea (syn. Erolia ferruginea)
- Stilt sandpiper Calidris himantopus (syn. Micropalama himantopus)
- Spoon-billed sandpiper Calidris pygmaea (syn. Eurynorhynchus pygmaeus)
- Red-necked stint Calidris ruficollis
- Temminck's stint Calidris temminckii
- Long-toed stint Calidris subminuta
- Buff-breasted sandpiper Calidris subruficollis (syn. Tryngites subruficollis)
- Sanderling Calidris alba (syn. Crocethia alba)
- Dunlin Calidris alpina
- Purple sandpiper Calidris maritima
- Rock sandpiper Calidris ptilocnemis
- Baird's sandpiper Calidris bairdii
- Pectoral sandpiper Calidris melanotos
- Semipalmated sandpiper Calidris pusilla (syn. Ereunetes pusillus)
- Western sandpiper Calidris mauri
- Little stint Calidris minuta
- Least sandpiper Calidris minutilla
- White-rumped sandpiper Calidris fuscicollis
The following species-level cladogram is based on a molecular phylogenetic study by David Černý and Rossy Natale that was published in 2022. Some of the nodes are only weakly supported by the sequence data.[12]
| Calidris |
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Hybrids
Several hybrids have been discovered between different species in the genus. See Hybridisation in shorebirds for further details.