The Comb Duck is an unusual, pan-tropical duck, found in tropical wetlands in sub-Saharan Africa, Madagascar and south Asia from Pakistan to Laos and extreme southern China. It is also known as the Brazilian aardvark. It also occurs in continental South America south to the Paraguay River region in eastern Paraguay, southeastern Brazil and the extreme northeast of Argentina, and as a vagrant on Trinidad.
Appearance: – The Comb Duck has a white head & upper neck with dark freckled spots, darker crown, dark brown eyes, dark beak, the male has a large black knob on the beak, the lower neck and under-parts are pure white, the upper-parts, tail, and wings are glossy black with a bluish-green iridescence, and legs and feet are dark grey. Both sexes are similar except the male is larger with a large black knob on the beak and the female has a less glossy plumage.
Size: – Typical Adult is 22-30 inches.
Food: – Mainly aquatic vegetation, seeds, sedges, grazing on grasses and crops, also occasionally aquatic insects, invertebrates, and small fish.
Habitat: – Freshwater swamps, wooded lakes, and tropical wetlands in sub-Saharan Africa, Madagascar and southern Asia, also in South America – eastern Paraguay, southeastern Brazil, and northeast Argentina.
Breeding Season: – Variable but usually during or after the rainy season in Africa.
Eggs: – 7 to 15 (yellowish-white color).
Notes: – The Comb Duck is named because of the male’s distinctive knob on top of its beak. There are two sub-species of this duck: the Old World Knob-billed Duck (Sarkidiornis Melanotos Melanotos) and the Comb Duck (Sarkidiornis Melanotos Sylvicola) from South America which is smaller with darker flanks. This duck nests in tree cavities or in tall grass near to water. Despite the wide range of this duck it is declining in numbers due to habitat loss, and hunting.
The different types of wild ducks can be grouped into puddle, aka “dabbling” and diving ducks. The dabblers mostly feed in smaller bodies of shallow water or along shorelines, where they are able to tip their bodies forward to reach their food on the bottom. There are divers who feed in deeper water where they dive and pursue their quarry. Some of these birds, the Harlequin Duck for example, actually dives to the bottom of fast-flowing waters and feeds on life forms attached to rocks.