The Marsh Sandpiper is a slender wader with a needle-like bill and long yellowish legs. In Peninsular Malaysia it is recorded as a migrant and nonbreeding visitor.
It has long yellowish legs and a needle-thin bill. Adult plumage on the head and breast differs between breeding (March–May) and nonbreeding (October–February); juveniles in August–September have brown on the head.
It feeds alone or in loose flocks, picking prey from the surface or probing with its head underwater. It often feeds in deeper water and swims comfortably.
It breeds in inland wetlands, making a shallow nest depression, often on a mound at the edge of a lagoon or pool. It nests alone or in small colonies.
Chicks leave the nest soon after hatching and feed themselves on insects and other small invertebrates.
Its food includes terrestrial and aquatic insects, small crustaceans, molluscs and fish.
In flight it has a long white back and rump, a pale tail and dark wings without wing-bars. Juvenile scapulars, coverts and tertials have brown centres and whitish edges.
An extinction-risk assessment has not been added yet.
The Uttarakhand factsheet describes the Marsh Sandpiper as a wetland winter migrant and assigns it high regional conservation priority. It lists both long-term and current annual trends as insufficient data.