whewer

Etymology
Century, Wright's English Dialect Dictionary and the 1933 OED take it to be from, and early cites also call the bird the "whistling widgeon".

Noun

 * 1)  whew duck, Eurasian wigeon, wigeon.
 * 2) * 1634, Althorp MS. in Simpkinson, Washingtons (1860), page xxiii:
 * Peckards 3—broadbills 5—whewers 2
 * 1) * 1668, Charleton, Onomast., page 100:
 * Boscas, aliis Anas Fistularis [...] the Whewer, or Whistling Widgeon.