Calidris is a genus of Arctic-breeding, strongly migratory wading birds in the family Scolopacidae.

Migratory shorebirds are shown to have decline in reproductive traits because of temporal changes of their breeding seasons.

This enables the birds to locate buried prey items, which they typically seek with restless running and probing.

[3] The genus Calidris was introduced in 1804 by the German naturalist Blasius Merrem with the red knot as the type species.

[4][5] The genus name is from Ancient Greek kalidris or skalidris, a term used by Aristotle for some grey-coloured waterside birds.