Anhimidae – Screamers

Commonly known as screamers, these birds are native to South America. This family is characterized by three species: the Southern Screamer (Chauna torquata), the Northern Screamer or Black-necked Screamer (Chauna chavaria), and the Horned Screamer (Anhima cornuta). These birds are quite distinct in appearance and behavior, making them unique among waterfowl.

Screamers are large birds, with some reaching up to 90 centimeters (3 feet) in length and a wingspan of approximately 1.6 meters (5.5 feet). Their physique resembles that of geese, with robust bodies and long necks, but their heads are more akin to that of a chicken, with a small, hooked beak. The legs of screamers are long and strong, equipped with three forward-facing toes and one backward-facing toe. The toes are partially webbed, which assists in swimming, though they are not as aquatic as ducks or geese.

A striking feature of screamers is the crest of feathers atop their head, which can be raised or lowered. Another remarkable trait is the presence of two sharp, bony spurs on their wings. These spurs are not just ornamental; screamers use them as weapons during territorial disputes or to fight for mates. Despite their somewhat aggressive defense mechanisms, screamers are generally peaceful birds.

Screamers are herbivorous, feeding mainly on plant material such as leaves, stems, and aquatic vegetation. They have a multi-chambered stomach similar to that of cattle, which ferments the vegetable matter they consume. This diet is somewhat unusual for large waterbirds and reflects their adaptation to the habitats they occupy.

One of the most notable behaviors of screamers is their vocalization. They are named for their loud, echoing calls, which can be heard over great distances, up to two kilometers away. These calls serve various purposes, from communication between mates or family members to territorial signals.