An adult Knot measures 23-26 cm (9-10 in) long with a 47-53 cm (18.5-21 in) wingspan. They have a small head and eyes, a short neck and a slightly tapering bill. It has short dark legs and a medium thin dark bill. The winter, or basic, plumage becomes uniformly pale grey, and is similar between the sexes. Breeding plumage is mottled grey on top with a cinnamon face, throat and breast and light-coloured rear belly. The alternate plumage of females is similar to that of the male except it is slightly lighter and the eye-line is less distinct. The large size, white wing bar and grey rump and tail make it easy to identify in flight.
Habitat and Distribution
They breed in tundra and the Arctic Cordillera in the far north of Canada, Europe, and Russia. North American breeders migrate to coastal areas in Europe and South America, while the Eurasian populations winter in Africa, Papua New Guinea, Australia, and New Zealand.
During breeding Knots eat mostly spiders, arthropods, and larvae obtained by surface pecking. In winter they eat a variety of hard-shelled prey such as bivalves, gastropods and small crabs that are ingested whole and crushed by a muscular stomach.
They breed in the moist tundra during June to August.
Calls and Songs
They give a low monosyllabic knutt call in flight and when migrating they utter a disyllabic knuup-knuup call.