The Red-knobbed Coot, also known as the Crested Coot, is a striking waterbird with a predominantly black plumage contrasted by a distinctive white frontal shield. It is a medium-sized bird, measuring 35–42 cm in length with a wingspan of 75–85 cm. The males, slightly larger than the females, weigh between 770 and 910 grams, while females range from 455 to 790 grams. Both sexes appear similar in plumage. The species is characterized by its long, strong toes with partial webbing, an adaptation to its aquatic lifestyle.
To distinguish the Red-knobbed Coot from its close relative, the Eurasian Coot, one must look for the two small red knobs atop the facial shield, which are only present during the breeding season and are not visible from afar. The black feathering between the shield and the bill is rounded, as opposed to the pointed feature in the Eurasian Coot. Additionally, the bill of the Red-knobbed Coot has a subtle bluish-grey hue. In flight, unlike the Eurasian Coot, it lacks the white trailing edge on its secondaries.
This coot favors freshwater lakes and ponds as its primary habitat, where it can be seen swimming or walking along the water's edge.
The Red-knobbed Coot is a resident breeder across much of Africa and can also be found in the southernmost parts of Spain.
The Red-knobbed Coot is known for its bold and less secretive nature compared to other members of the rail family. It exhibits strong territorial behavior during the breeding season and is known to be quite aggressive, even towards larger birds. It swims with a characteristic bobbing of the head and is capable of short dives. When taking off for flight, it runs across the water surface, creating a noticeable commotion.
Both sexes contribute to building a bulky platform nest of reeds and plant stems, often situated in shallow water. The female lays a clutch of 5–7 eggs, which are incubated by both parents for 18–25 days. The precocial chicks are mobile shortly after hatching and receive parental care for about 55–60 days.
An omnivorous bird, the Red-knobbed Coot feeds on a variety of small live prey, including the eggs of other water birds. It predominantly consumes waterweeds, such as Potamogeton species, for which it will dive.
The Red-knobbed Coot is currently listed as Least Concern on the IUCN Red List, indicating that it is not at immediate risk of widespread decline.
During mating, the Red-knobbed Coot is quite vocal, emitting a variety of sounds including a fast "kerrre" similar to the Little Crake, a harsh "ka-haa," and a grunting "oot oot" hoot. These vocalizations are distinct from those of the Eurasian Coot.