"About 100,000 Snow Geese that breed on Wrangel Island in Siberia migrate along the Pacific Coast to spend the winter in Washington State and California. About half of these birds stop on the Fraser River delta between late September and early December to feed on the underground roots of sedges and bullrushes growing at the river's mouth and farm crops on the delta. Dr. Sean Boyd of the Canadian Wildlife Service in Delta, B. C. has been studying the feeding habits of Snow Geese for many years. . . ."

Environment Canada

They winter here from October to March before heading to Wrangel Island (Ostrov Vrangelya), off the coast of northeastern Siberia.