This shy and nervous species, which will quickly fly off if approached, may be seen in large flocks outside of the breeding season, but usually occurs in pairs or small groups (2). The breeding season is thought to extend between March and November, with a peak in activity in July and August, although this may vary throughout the range (2). The Philippine duck constructs a nest obscured from view under a thick cover of aquatic vegetation, such as water bindweed. Clutches consist of 8 to 10, sometimes 15 to 16, eggs, which are dull white with a brownish tinge. These are incubated for 25 to 26 days (2).
Most active in the early morning, late afternoon, and during moonlit nights, the Philippine duck forages in shallow water for plants, molluscs and crustaceans (2). Fish and frogs may also be consumed, as well as insects, rice and the shoots of young plants; some farmers have complained of the damage this duck had done to newly sown fields and sprouting crops (4).