The male Comb Duck develops a large knob at the base of its bill. It feeds mainly on aquatic plants and seeds and nests in tree hollows near water.
The male's back has a blue-green and purple gloss, and a large fleshy knob rises at the bill base. The female lacks the knob and is smaller and duller.
It eats shoots and seeds of aquatic and marsh plants, including wild and cultivated rice. It nests in a tree hollow near water, lined with leaves, grasses, and feathers.
An extinction-risk assessment has not been added yet.