A denizen of rivers, wetlands, lakes, lagoons, estuaries, dams, ponds and pans with still water and surrounded by dense vegetation, the Red-knobbed Coot follows an omnivorous diet of aquatic plants, algae, molluscs, crustaceans, insects and the eggs of other waterbirds. Adults can weigh up to 1kg.
Red-knobbed Coots are solitary breeders, pairs establishing a territory in which to raise their young. They are very aggressive, both towards their own kind and other species of waterfowl. in South Africa they breed at any time of the year. Nests are platforms built of aquatic plant material on open water or among emergent vegetation. When not breeding they are more gregarious, occasionally congregating in flocks that number more than a thousand birds.
The Red-knobbed Coot has a wide distribution in East and Southern Africa and a population estimated at over a million, though declining mostly through habitat loss, and considered of Least Concern by the IUCN. There is an isolated, threatened population in Morocco and Southern Spain. They can be found commonly all over South Africa where suitable habitat exists, including on farm dams and rivers in the arid west of the country, expanding their range in response to the building of suitable artificial waterbodies.