Red Knot
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{{Taxobox | color = pink | name = Red Knot | status = Conservation status: Lower risk (lc) | image = Knot feeding.jpg | image_width = 200px | image_caption = Red Knots (winter plumage) | regnum = Animalia | phylum = Chordata | classis = Aves | ordo = Charadriiformes | familia = Scolopacidae | genus = Calidris | species = C. canutus | binomial = Calidris canutus | binomial_authority = Linnaeus, 1758 }} The Red Knot, Calidris canutus (just Knot in Europe), is a medium sized shorebird which breeds in tundra in the far north of Canada, Europe and Russia. North American birds winter in coastal areas on the Atlantic and Pacific coasts as far south as Argentina. Old World birds migrate to the Mediterranean, the British Isles, Africa and Australasia. This species forms enormous flocks in winter.
The Red Knot nests on the ground near water, usually inland. The female lays 3 to 4 eggs in a shallow scrape lined with leaves and moss. Both parents look after the young, but the female leaves before the young are able to fly.
The adult Red Knot is 23-26 cm long with a 47-53 cm wingspan. It has short dark legs and a medium thin dark bill. The body is mottled grey on top with a cinnamon face, throat and breast and light-coloured rear belly. In winter the plumage becomes uniformly pale grey.
There are four subspecies; C. c. canutus, C. c. piersmai, C. c. rogersi, C. c. roselaari, C. c. rufa and C. c. islandicus.
The weight varies with subspecies, but is between 100 and 200 grams with islandicus the heaviest. Red Knots double their weight prior to migration.
These birds forage on mudflats and beaches, probing or picking up food by sight. They mainly eat mollusks and insects, also plant material.
Near the end of the 19th century, large numbers of Knot were shot for food during migration in North America. This bird's numbers have declined in that continent in more recent times due to extensive harvesting of Horseshoe crabs in Delaware Bay, a critical stopover point during spring migration; the birds refuel by eating the eggs laid by these crabs.
It is sometimes said that the Red Knot gets its name from King Cnut, but there is no factual basis for this story. A more likely etymology is that the name is onomatopoeic, based on the bird's grunting call note.
Reference
- Shorebirds by Hayman, Marchant and Prater ISBN 0-873403-19-4
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