It walks well, without waddling, and although it normally feeds by upending, it can dive if necessary.[18] It does not often perch in trees, unlike other whistling ducks. It flies at low altitude with slow wingbeats and trailing feet, in loose flocks rather than tight formation. It feeds during the day and at night in fairly large flocks, often with other whistling duck species, but rests or sleeps in smaller groups in the middle of the day.[17] They are noisy and display their aggression towards other individuals by throwing back their heads.