Beach thick-knee
Esacus magnirostris
TAXONOMY
Edicnemus magnirostris Vieillot, 1818, Depuch Island, Western Australia. Monotypic.
OTHER COMMON NAMES
English: Beach stone curlew, beach curlew, Australian stoneplover; French: Oedicnème des récifs; German: Rifftriel; Spanish: Alcaraván Picogruesco Australiano.
PHYSICAL CHARACTERISTICS
21–22.5 in (53–57 cm) The largest thick-knee, massively built and thick-legged, with a long, strongly-upcurved bill. Plain gray-brown above, marked with a blackish shoulder bordered below by a thin white line, above pale gray wing coverts; rusty patch under tail. Dark crown and black cheek stripe separated by wide white stripe over eye; white lower cheek and throat patch. Bill largely black with small yellow base; eyes and legs yellow.
DISTRIBUTION
Scattered through the Andaman Islands to the Philippines, Indonesia, New Guinea, and many islands of the Southwest Pacific, and south to the north and northeast coasts of Australia.
HABITAT
Found on island shores and mainland beaches, whether of sand, shingle, rocks, or mud, in wide open spaces or restricted to narrow beaches fringed by mangroves or rocks. Often feeds in intertidal areas and equally at home on windswept estuaries, sheltered river mouths, and exposed rocks.
BEHAVIOR
Usually found along the beach close to the water's edge, the beach thick-knee tends to fly off over the sea if disturbed before sweeping back to the shore. It may resort to undisturbed dunes and sand flats a little way inland, or even to the shores of shallow, coastal lagoons. It will rest on offshore reefs, and even enters quite tall and moderately dense mangroves.
FEEDING ECOLOGY AND DIET
The main food is crabs, where they are common, but other crustaceans may also be taken when crabs are scarce. Larger crabs are broken up before being swallowed. Typical feeding technique is a slow, quiet stalk, followed by a lunge or sudden fast run to snatch up prey, but the beach thick-knee will also probe mud and sand. It does not wade in water.
REPRODUCTIVE BIOLOGY
Monogamous. Breeds at low density in isolated pairs, frequenting regular territories for many seasons. The nest, on a sand-bank or spit, is a simple depression, occasionally ringed (but not lined) with bits of vegetation. Lays just one egg, which is incubated for 30 days; young develop slowly and fly after 12 weeks, but they remain with adults for up to a year.
CONSERVATION STATUS
Locally secure but in general faces increasing threats from disturbance as beaches are subject to human pressures, including tourist and hotel development, off-road vehicles on beaches, and other disruptive activities. Faces potentially large, locally catastrophic, but uncertain threats from rising sea levels with global climate change.
SIGNIFICANCE TO HUMANS
None known.
