Knot, or Red Knot, a shore bird found throughout much of the world. It nests on the tundra in the Arctic, and winters in the Southern Hemisphere. Some knots have been known to migrate as far south as Tierra del Fuego, South Africa, and New Zealand. During migrations, flocks of knots are often seen feeding in tidal mudflats and marshes along the eastern coast of North America and on the rocky shores of western Europe. The knot is a chunky bird with gray-brown upperparts and a reddish breast. Knots feed on insects, spiders, mollusks, crab eggs, and crustaceans.

The knot is Calidris canutus of the sandpiper family, Scolopacidae. The great knot is C. tenuirostris.