Studies on the function of rattling calls and mewing notes would be important since the calling rate differed according to the association with macaques.
Calls include soft mewing notes, and a pulsing, purring trill when agitated.
Other descriptions include a soft squeal or whistle and a shrill gull-like mewing.
Their voice consists of mostly mewing and squealing notes.
It is usually silent except for mewing and wailing notes while on the breeding grounds.
They can be quite noisy, making various loud cheeping, mewing and grating calls.
The drake's distinctive call, a mewing "weee-ooooo", is given during courtship.
Calves will emit snorts, bleats, mooing and mewing sounds.