About Arenaria interpres (Linnaeus, 1758)
This bird, the ruddy turnstone, has the scientific name Arenaria interpres (Linnaeus, 1758). It is a fairly small, stocky wader, measuring 22–24 cm (8.7–9.4 in) in length, with a 50–57 cm (20–22 in) wingspan, and weighing 85–150 g (3.0–5.3 oz). It has a dark, slightly upturned wedge-shaped bill 2–2.5 cm (0.79–0.98 in) long, and fairly short bright orange legs 3.5 cm (1.4 in) long. Its plumage is dominated by a harlequin-like pattern of brown, black, and white in all seasons. Breeding individuals have reddish-brown upperparts with black markings; the head is mostly white with black streaks on the crown and a black facial pattern. The breast is mostly black with a white patch on the sides, and the rest of the underparts are white. In flight, it shows a white wingbar, a white patch near the wing base, and white lower back, rump, and tail, with dark bands on the uppertail-coverts and near the tail tip. Females are slightly duller than males, with a browner head that has more streaking. Non-breeding adults are duller than breeding birds, with dark grey-brown upperparts with black mottling and a dark head with little white. Juvenile birds have a pale brown head, and pale fringes on upperpart feathers that create a scaly appearance. The subspecies A. i. morinella is marginally smaller, with darker upperparts and less streaking on the crown. The ruddy turnstone has a staccato, rattling call, and a chattering alarm call that is mainly given during the breeding season. The ruddy turnstone breeds in northern latitudes, usually within a few kilometers of the sea. Subspecies A. i. morinella occurs in northern Alaska and Arctic Canada as far east as Baffin Island. Subspecies A. i. interpres breeds in western Alaska, Ellesmere Island, Greenland, Norway, Denmark, Sweden, Finland, Estonia, and northern Russia. It formerly bred on Germany’s Baltic coast, and may have bred in Scotland and the Faroe Islands. In the Americas, this species winters on coastlines from Washington and Massachusetts south to the southern tip of South America; it is scarce in southern Chile and Argentina, and is only an unconfirmed vagrant in the Falkland Islands. In Europe, it winters in western regions from Iceland, Norway, and Denmark southward, with only small numbers found on Mediterranean coasts. In Africa, it is common all the way south to South Africa, with large populations on many offshore islands. In Asia, it is widespread in the south, and wintering birds range as far north as southern China and Japan, mainly in the Ryukyu Islands. It occurs south to Tasmania and New Zealand, and is present on many Pacific islands. Some non-breeding birds stay year-round across many parts of the wintering range, and some of these birds still develop breeding plumage in spring and summer. Ruddy turnstones can survive in a wide range of habitats and climatic conditions, from Arctic to tropical environments. Their typical breeding habitat is open tundra located near water. Outside the breeding season, they live along coasts, particularly on rocky or stony shores. They are often found on human-made structures such as breakwaters and jetties, and may venture onto open grassy areas near the coast. Small numbers sometimes appear on inland wetlands, especially during spring and autumn migration. Ruddy turnstones are particularly faithful to specific wintering sites. A 2009 study of turnstones wintering along a stretch of coastline in the Firth of Clyde found that 95% of birds resident to the area at the end of winter returned the following autumn. The same study also confirmed the ruddy turnstone is one of the longest-lived wader species, with annual adult mortality rates under 15%. Its average lifespan is 9 years, and the longest recorded lifespan is 20 years. The ruddy turnstone is a monogamous species, and pairs may stay together for more than one breeding season. The nest is a shallow scrape about 11 cm (4.3 in) across and 3 cm (1.2 in) deep, often lined with leaves. It may be built among vegetation or on bare stony or rocky ground, and multiple pairs may nest close together. A single clutch of two to five eggs is laid, with four being the most common. Eggs measure about 41 mm × 29 mm (1.6 in × 1.1 in) and weigh around 17.9 g (0.63 oz). They are smooth, slightly glossy, and shaped oval to pear-shaped. Their colour varies, but they are commonly pale green-brown with dark brown markings that are densest at the larger end. Incubation starts when the first egg is laid and lasts 22–24 days. The female is mainly responsible for incubating eggs, but the male may help toward the end. Young birds are precocial and can leave the nest soon after hatching. They are buff above with dark grey markings and white below. They can feed themselves, but are protected by their parents, particularly the male. They fledge after 19–21 days.
