Wing 325-376 mm
The Blue-winged Goose inhabits plateau marshes, streams and damp grasslands from about 1800 meters (6000 feet) upward. Pairs or small parties of three to five of these geese are common and easily seen at high elevations in small stream valleys and in pools and marshes in the moorlands where giant lobelia, alchemilla and tussock grass predominate and where they nest in March, April, June and September. During the big rains of July, August and September Blue-winged Geese flock in groups that may include 50 to 100 or more individuals which at this time probably undergo molt, losing the flight feathers. In the big rains the flocks also move to lower elevations of the plateau: for example, in one day in August 165 Individuals were counted at Gafersa Reservoir, some 20 kilometers west of Addis Ababa.
The goose has a peculiar habit, whether standing or walking, of resting its neck on its back. Indeed this posture together with the comparatively dull body color and bluish wing-patches are useful marks for identifying the species. Another characteristic habit of the goose can be observed during pair formation when the male struts around the female, his head bent over his back, and his bill pointed skywards or even behind him, exposing his blue wing patch and uttering a rapidly repeated soft, barely audible whistle, a “wnee-whu-whu-whu-whu-whu-whu-whu”. Parties of this goose, like other geese, station sentinels at the periphery of the flock. An alarmed goose produces a soft “whew-whu-whu-wliu” and, when forced into flight, a rather nasal bark, a “penk, penk-penk”, uttered at take-off but not in flight.
Studies of captive Blue-winged Geese suggest that they are largely active at night, which perhaps explain why so little is known about the species. This goose lays four to seven cream-colored eggs; the nestling is largely black with various silvery-white markings above, silvery-white below; the immature is similar to but duller than the adult. In total numbers the Blue-winged Goose seems to be one of the least numerous of any species of goose in the world. In Africa it is unique: its closest living relative lives in South America.