Australian Shelduck
Tadorna tadornoides
The males are mostly dark, with a chestnut breast. They have white neck collars and dark green heads. The females are similar, but they have white around the eyes and are smaller. Both males and females have chestnut and black wings with a green speculum, and show some white on their wings during flight. The downy young are white with a brown crown and brown stripes from crown to tail. Juvenile males are duller than the adults and also lack a white collar, while juvenile females have a lot more white on their excluding their crown.
ID text from Wikipedia, CC BY-SA 4.0
Ruddy Shelduck
Tadorna ferruginea
The ruddy shelduck grows to a length of 58 to 70 cm (23 to 28 in) and has a 110–135 cm (43–53 in) wingspan. The male has orange-brown body plumage and a paler, orange-brown head and neck, separated from the body by a narrow black collar. The rump, flight feathers, tail-coverts and tail feathers are black and there are iridescent green speculum feathers on the inner surfaces of the wings. Both upper and lower wing-coverts are white, this feature being particularly noticeable in flight but hardly visible when the bird is at rest. The bill is black and the legs are dark grey.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
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