Ruddy Turnstone

AT A GLANCE
Common Name: Ruddy Turnstone
Scientific Name: Arenaria interpres
Category: Birds
Subcategory: Shorebirds
Size: Length 21 to 26 cm (8.3 to 10.2 in); wingspan 50 to 57 cm (20 to 22 in)
Weight: 85 to 150 g (3.0 to 5.3 oz)
Lifespan: 9 to 14 years (record 19 years)
Diet: Omnivorous shoreline forager (crustaceans, mollusks, insects, worms, fish eggs, and carrion)
Habitat: Rocky sea coasts, barnacle-covered jetties, and Arctic tundra nesting ridges
Range: Circumpolar Arctic breeding; global coastal migration
Conservation Status: Least Concern (IUCN Red List)

Overview

The Ruddy Turnstone (Arenaria interpres) is a bold, energetic globe-trotting shorebird famous for its unique foraging technique of physically flipping over beach stones, shells, and seaweed clumps to snatch hiding crustaceans. Breeding in the high Arctic tundra and wintering along rocky coastlines on every continent except Antarctica, it is instantly recognized by its striking calico breeding plumage of chestnut, black, and white.

Biology and Physical Characteristics

Arenaria interpres has a stocky, short-legged build with bright orange legs and a stout, slightly upturned chisel-like black bill. In breeding plumage, it displays a harlequin head pattern of stark black and white, a bold black chest bib, and rich chestnut-russet feathering across its back and wings. In flight, it reveals an eye-catching pattern of flashing white stripes along its back and wings.

Behavior and Ecology

True to its name, the Ruddy Turnstone is a tireless stone-flipper. Running along pebble beaches and barnacle-encrusted jetties, it inserts its wedge-shaped bill beneath stones, shells, and thick tangles of washed-up kelp, flicking them over with a powerful upward heave of its neck muscles to seize sand fleas, beach hoppers, and small crabs. It is also an opportunistic consumer of horseshoe crab eggs and bird eggs.

Conservation and Human Impact

Assessed as Least Concern by the IUCN, the Ruddy Turnstone maintains a vast global distribution. However, long-term monitoring shows moderate declines driven by climate change in Arctic breeding tundra, coastal habitat loss, and declining horseshoe crab spawning populations at critical spring migratory stopover sites like Delaware Bay.

Interesting Factoid

The Ruddy Turnstone is a biological heavyweight lifter: using its muscular neck and chisel-like bill, this small 4-ounce shorebird can flip over beach stones and shells that weigh almost as much as its own body.