Although wavey is ultimately derived from an Algonkian onomatopoeic word for a goose, the present form may have been influenced by that of the Canadian French borrowing of the same term.
1743  (1949)  . . . the white geese . . . they [Crees] style wappawawewuck) which the English call's weywey's.
1820  (1823)  On the way back Hepburn and Keskarrah shot several waveys . . . .
1965  Even children can talk goose language. They call the wavies down to the hunter's guns.