The ruddy turnstone (Arenaria interpres) is a small cosmopolitan wading bird, one of two species of turnstone in the genus Arenaria.

It is now classified in the sandpiper family Scolopacidae but was formerly sometimes placed in the plover family Charadriidae. It is a highly migratory bird, breeding in northern parts of Eurasia and North America, and flying south to winter on coastlines almost worldwide. It is the only species of turnstone in much of its range and is often known simply as turnstone.

Taxonomy

The ruddy turnstone was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae under the binomial name Tringa interpres. The species is now placed together with the black turnstone in the genus Arenaria that was introduced by the French zoologist Mathurin Jacques Brisson in 1760 with the ruddy turnstone as the type species. The genus name arenaria is from Latin , "inhabiting sand", from , "sand". The specific interpres means "messenger"; when visiting Gotland in 1741, Linnaeus thought that the Swedish word , meaning "interpreter" applied to this species, but in the local dialect the word means "legs" and is used for the redshank.

Two subspecies are recognised:

In all seasons, the plumage is dominated by a harlequin-like pattern of brown, black and white. Breeding birds have reddish-brown upper parts with black markings. The head is mainly white with black streaks on the crown and a black pattern on the face. The breast is mainly black apart from a white patch on the sides. The rest of the underparts are white. In flight it reveals a white wingbar, white patch near the base of the wing and white lower back, rump and tail with dark bands on the uppertail-coverts and near the tip of the tail. The female is slightly duller than the male and has a browner head with more streaking. and plant material but it feeds mainly on invertebrates. Insects and their larvae

They have also been observed preying on the eggs of other bird species such as gulls, terns, ducks, and even other turnstones, though this behaviour is uncommon. In the majority of observed cases, turnstones typically go after undefended or unattended nests, puncturing the shells with their beaks to get at the contents within.

Reproduction

right|thumb|Breeding-plumaged adult on nest

It is a monogamous bird and pairs may remain together for more than one breeding season. The nest is a shallow scrape, often with a lining of leaves. It is about across and deep. It may be built amongst vegetation or on bare stony or rocky ground. Several pairs may nest close together. They estimate that the Canadian population is 100,000–500,000 adults. The Canadian Wildlife Service estimates that the worldwide population of ruddy turnstones is 449,000, and that 235,000 are breeding in North America while the rest are breeding throughout the Arctic regions. They are very common and widespread. Their remote breeding range and widespread winter range should help them remain a common species.

  • Ruddy turnstone Species Account – Cornell Lab of Ornithology
  • Ruddy turnstone profile at BirdWeb.org
  • Ruddy Turnstone Population Assessment Summary – Environment Canada
  • Ruddy turnstone species text in The Atlas of Southern African Birds
  • Encounter between ruddy turnstone Arenaria interpres and hermit crab Coenobita perlatus
  • Video of ruddy turnstones in Swansea Bay, Wales, U.K.
  • Ruddy turnstone Structured guide to the species in southern Africa