American Coot
Fulica americana
The American coot measures 34–43 cm (13–17 in) in length with a wingspan of 58 to 71 cm (23 to 28 in). Adults have a short, thick, white bill and white frontal shield, which usually has a reddish-brown spot near the top of the bill between the eyes. Males and females look alike, but females are smaller. Body mass in females ranges from 427 to 628 g (0.941 to 1.385 lb) and in males from 576 to 848 g (1.270 to 1.870 lb). Juvenile birds have olive-brown crowns and a gray body. They become adult-colored around 4 months of age. Voice: The American coot has a variety of repeated calls and sounds. Male and female coots make different types of calls to similar situations. Male alarm calls are puhlk while female alarm calls are poonk. Also, stressed males go puhk-cowah or pow-ur while females call cooah.
ID text from Wikipedia, CC BY-SA 4.0
Red-knobbed Coot
Fulica cristata
The red-knobbed coot is largely black except for the white frontal shield. It is 35–42 cm (14–17 in) long, spans 75–85 cm (30–33 in) across the wings. Males weigh 770–910 g (27–32 oz), females are slightly smaller and weigh 455–790 g (16.0–27.9 oz). The sexes are alike. As a swimming species, it has partial webbing on its long strong toes. The juvenile is paler than the adult, has a whitish breast, and lacks the facial shield; the adult's black plumage develops when about 3–4 months old, but the white shield is only fully developed at about one year old, some time later.
ID text from Wikipedia, CC BY-SA 4.0
Where you might meet both
Learn this pair in BeakBrain
Photo and call practice, free in any browser.
Play BeakBrainPhotos and recordings are credited to their authors under the licence shown. Full profiles: American Coot and Red-knobbed Coot.