Grauweihe Circus cinereus

Fairly common in open country of Patagonia, often near lakes and marshes; uncommon and local northward. Male silvery gray overall with fine rusty barring below. Female and immature are grayish brown above; underparts barred on female, streaked on immature. All plumage have white rump band. Usually seen in flight, hunting low over open country with wings held in a shallow V, tilting side to side like a Turkey Vulture. Perches on ground and fence posts, not in trees or up high.