Ruddy Turnstone

(Arenaria interpres) (RUTU)

Photographic Identification Guide

The stout, short-legged Ruddy Turnstone (Arenaria interpres) (RUTU) has colorful breeding plumage and is a circumpolar breeder. It is almost unmistakable in any plumage due to its thick orange legs and feet.

Historically a relatively common migrant on New England shores, RUTU has undergone drastic drop-offs in populations in the past four to five decades. Migrating RUTU in spring, along with Sanderling (SAND), Red Knot (REKN) and other shorebird species, depend heavily on a feast of Horseshoe Crab eggs in Delaware Bay. This food resource has been reduced due to human hunting and killing of Horseshoe Crabs for use in medical labs and for fishing bait and pet food. Many of the birds, deprived of a rich food resource, are either unable to complete their migration to the Arctic where they breed, or once there, do not have enough fat reserves to breed successfully.

The State of New Jersey has limited human access to some of the beaches where Horseshoe Crabs come ashore in May to spawn. This has resulted in limited but noticeable reduction in the rate of population decline in affected shorebird populations.

In this guide, we cover the features, in order of importance, to look for on these birds. When discussing plumages, we use the terms winter, spring, and summer to refer to northern hemisphere seasons. Because some of these birds spend parts of the year in the northern and southern hemispheres, the correct technical terms for the plumage stages—basic and alternate—help avoid the confusion of seasonal terminology.

visual gallery

species account

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Fig.15. Ruddy Turnstones compared to Sanderling. Note turnstone’s chunky body, chisel-shaped bill and, thick, short, orange legs. Bolivar Peninsula, TX.; 18 October 2017.
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Fig. 14. Ruddy Turnstone in flight. Parker River National Wildlife Refuge. 31 May 2021.
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Fig. 13. Ruddy Turnstone. Juvenile molting to winter (basic) plumage. Pleasure Bay, South Boston, MA. 21 November 2017.
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Fig. 12. Ruddy Turnstone. Juvenile in worn plumage. Winthrop Beach, Winthrop, MA. 1 October 2016.
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Fig. 11. Ruddy Turnstone. Juvenile in fresh plumage. Duxbury Beach, Duxbury, MA. 4 September 2021.
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Fig. 10. Ruddy Turnstone. Summer (alternate) molting to winter (basic) plumage. Winthrop Beach, Winthrop, MA. 6 November 2017.
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Fig. 9. Ruddy Turnstone. Summer (alternate) molting to winter (basic) plumage. Bolivar Flats, TX. 18 October 2017.
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Fig. 8. Ruddy Turnstones. Variation in molt from summer (alternate) to winter (basic) plumage. Winthrop Beach, Winthrop, MA. 17 October 2016.
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Fig. 7. Ruddy Turnstone. Worn and faded summer (alternate) plumage. Napatree Point, RI. 2 August 2017.
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Fig. 6. Ruddy Turnstone. Worn summer (alternate) plumage. Winthrop Beach, Winthrop, MA. 24 August 2015.
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Fig. 5. Ruddy Turnstone. Spring (alternate) plumaged female with smudged black, brown and white on upper back and nape. Winthrop Beach, Winthrop, MA. 3 June 2023.
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Fig. 4. Ruddy Turnstone. Spring (alternate) plumaged male with black on upper back, white on nape. Bolivar Peninsula, TX. 10 May 2015.
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Fig. 3. Ruddy Turnstones, spring (alternate) plumage. Winthrop Beach, Winthrop, MA. 3 June 2023.
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Fig. 2. Ruddy Turnstones roosting. Coarsely patterned winter (basic) plumage. Pleasure Bay, South Boston, MA. 8 February 2023.
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Fig. 1. Ruddy Turnstone. Winter (basic) plumage. Pleasure Bay, South Boston, MA. 29 December 2018.

The photos in this species account are arranged in this order:

Basic: winter plumage, roughly November to March.

RUTU acquires winter (basic) plumage toward the end of the calendar year, usually when it approaches or arrives at its winter range; see Fig. 1, Fig. 2.

Alternate: first spring and summer after hatch year or adult breeding plumage, March to November.

Beginning in spring, winter (basic) feathers on RUTU are gradually replaced by alternate feathers; see Fig. 4. Most alternate feathers last until fall of the same year; replacement by winter (basic) feathers begins in August; see Fig. 7. Among different individuals in this species, the molt schedule and pattern are extremely varied.

Juvenile: young birds, recently hatched, July to October.

See Fig. 11. These feathers are acquired on the breeding grounds immediately after the natal down is shed and before the young begin their southbound migration.

Size and weight

Females are slightly larger and heavier than males.

Body length:

8.75–9.5 in. (22.2–24.1 cm)

Wingspan:

20–22 in. (50.8–55.9 cm)

Bill length:

0.9–1 in. (22.4–24.2 mm)

Weight:

3–4.5 oz. (86–128 g)

Calls

Alarm call, given primarily in flight, is a distinctive rat-a-tat.

Calls in Merrit Island NWR, FL, 2018:

Calls at Cocoa Beach, FL, 2014:

Plumage and other characteristics

RUTU’s legs are orange throughout the year. Young birds always have pale legs, which may be dusky or pinkish on some individuals; see Fig. 1.

The bill is black, chisel-shaped and often slightly upturned; see Fig. 1.

RUTU’s distinguishing plumage characteristic is twin-lobed dark breast markings; see Fig. 1.

Winter (basic) plumage of RUTU, like most winter shorebirds, is brownish gray. Gray mantle feathers are bisected by a darker central shaft; see Fig. 1. Note the relatively coarse look created by unusually large mantle feathers; see Fig. 2.

Unmistakably distinct from all other shorebirds, spring-plumaged (alternate) birds have bright rusty upperparts interspersed with patches of black feathers, a harlequin head—mostly white with black markings—and large, twin lobes of black feathers on the breast; see Fig. 3, Fig. 4.

Males have black across the lower nape and on the central upper back; see Fig. 3, Fig. 4. Females have a smudged crown, more black spotting on the wings and a mottled nape and central upper back; see Fig. 3, Fig. 5.

Spring (alternate) and summer (alternate) plumage are the same plumage, though more worn on the margins in summer; see Fig. 6.

By August, some of the colorful, rusty alternate plumage begins to fade or be replaced by winter (basic) feathers; see Fig. 7, Fig. 8, Fig. 9, Fig. 10.

Newly fledged young birds arrive from the Arctic in late summer displaying the characteristic fresh, evenly patterned, scaly look of all young shorebirds; see Fig. 11, Fig. 12. Fig. 13 illustrates a juvenile bird partially molted to winter (basic) plumage in November.

RUTU has a distinctive pied pattern in flight, with multiple longitudinal white lines across its back, bold white wing stripes and a white base to the mostly blackish tail; see Fig. 14.

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Breeding range, migration, wintering range, habitat

RUTU is a circumpolar nester along the shores of the Arctic Ocean. Ruddy Turnstones are among the northernmost nesting shorebirds in North America and Eurasia.

Wintering range in the Western Hemisphere includes the coast of California, the east coast of North America from Nova Scotia south to United States Gulf coast, the Caribbean islands, both coasts of Mexico and Central America, and both coasts of South America south to central Chile and northern Argentina.

RUTU’s vast wintering range also includes the southern coasts of Scandinavia, the coasts of the British Isles, the Atlantic coast of Western Europe, most of the African coast, the coast of Arabia, the coasts of central and south Asia, the coasts of the Indonesian Islands and the coasts of Australia and New Zealand.

In spring, most Ruddy Turnstones migrate along the coast, appearing in Massachusetts and other New England coastal sites in mid- to late May and departing rapidly for breeding habitats in the Arctic.

After the breeding season, southbound adults reappear on our shores in July and August, departing gradually through the later fall months, though a few linger and often winter along the Massachusetts coast.

RUTU feeds on sandy or muddy beaches with other small sandpipers. Turnstones are also often found on rocky or pebbly shores where they use the sturdy bill to flip over shells and pebbles to forage for food.

At higher tides, RUTU roosts, often with other shorebirds, on higher dunes, in salt marshes or salt pans, or on rocky higher beaches, jetties or breakwaters.

Similar species

Comparison with other sandpipers

RUTU is the only sandpiper with orange legs. It is also chunkier and has a stouter bill and thicker legs than most other small sandpipers; see Fig. 15 for comparison to Sanderling.