The Maccoa duck (Oxyura maccoa) is a stiff-tailed diving duck found across Eastern and Southern Africa.
As members of the stiff-tailed duck group, Maccoas are often found wading in the water with their tail feathers cocked upwards. As diving ducks, their bodies are specialized for being agile underwater swimmers and thus have sacrificed the characteristics that allow them to move well on land. As a result, their legs are set further back on their bodies which makes them awkward when walking out of water.
The breeding male Maccoa stands out with its cobalt blue bill extending from a completely black head and throat. The breast and back are chestnut coloured while the underparts are often greyish-brown, the rump is dark brown, and the tail and feet are black. In flight, the male's off-white underwing feathers and white axillaries can be seen. Non-breeding males closely resemble the females, except for a few points: a darker crown and hints of chestnut colour on the back.
The female Maccoa is less colourful. It boasts a greyish-black bill with a light tip, and a light brown face with a dark crown and cheek stripe, and an off-white throat. The female also has a light brown breast, darker brown back, off-white underparts, black feet and black tail feathers.
As with many birds, juvenile Maccoa ducks have similar plumage to adult females. However, their tail feathers are slimmer and notched, and their crowns are a darker brown.