From page 235 in Waterfowl of North America, Europe, and Asia:
A snow goose can be very loquacious, even noisy, especially in flight, when taking off or landing. It produces loud, raucous, barking calls gwok or ga-ik, as well as other sounds more like those of grey geese, lower and hoarser: gung, wa-iir or hun-hrr. Large flocks utter these calls continuously and at different pitches, linked to the birds’ size.
Waterfowl of North America, Europe, and Asia
An Identification Guide
This is the ultimate guide for anyone who wants to identify the ducks, geese, and swans of North America, Europe, and Asia. With 72 stunning color plates (that include more than 920 drawings), over 650 superb photos, and in-depth descriptions, this book brings together the most current information on 84 species of Eurasian and North American waterfowl, and on more than 100 hybrids. The guide delves into taxonomy, identification features, determination of age and sex, geographic variations, measurements, voice, molt, and hybridization. In addition, the status of each species is treated with up-to-date details on distribution, population size, habitats, and life cycle. Color plates and photos are accompanied by informative captions and 85 distribution maps are also provided. Taken together, this is an unrivaled, must-have reference for any birder with an interest in the world’s waterfowl.