Sharp-tailed Sandpiper

Overview

The sharp-tailed sandpiper (Calidris acuminata) is a small-to-medium migratory wader found primarily in Siberia during the summer breeding period and in Australia for wintering. It is currently classified as Vulnerable by the IUCN, with a decreasing population trend attributed largely to habitat loss and disturbance.

Identification

• 22 cm in length with a portly build featuring a pot belly, flat back, and somewhat drawn-out rear end.
• Mottled chestnut-brown upper body with sharp-looking feathers that have a dark centre, complemented by a chestnut cap and a brown stripe through the eye.
• Dark grey to black straight bill and olive- to yellow-coloured legs, with white or pale underparts featuring similar mottling on the breast and belly sides.
• Distinguished from similar species by a stronger supercilium, a more chestnut-coloured crown, and chevron-shaped marks on the flanks rather than a strongly demarcated breast band.

Habitat

Breeding occurs exclusively in eastern Siberian tundra composed of peat-hummock and lichen. During migration and winter, they favour the muddy edges of shallow freshwater or brackish wetlands, including swamps, lakes, lagoons, and salt marshes, with a particular preference for inland freshwater wetlands in Australia. They also utilise coastal mudflats, sewage farms, and rocky shores when ephemeral terrestrial wetlands dry out.

Diet

Foraging takes place on the edges of wetlands, intertidal mudflats, and among inundated vegetation, where they pick up food by sight or probe for it. Their diet consists mainly of aquatic insects, molluscs, crustaceans, and worms, with occasional consumption of seeds and other invertebrates. They also forage on dry or wet mats of algae, among rotting seaweed, and on short grass in paddocks after rain.

Did you know?

Some individuals undertake a presumed non-stop trans-Pacific flight of more than 10,000 km to reach Australia and New Zealand after fattening up in Alaska.