Red-legged seriema a fan-shaped crest. Many other characteristics are shared with the black-legged seriema ("Chunga burmeisteri"), the only other living member of its family. Some of these traits are discussed in the Cariamidae article. The song has a quality described as "a cross between 'the serrated bark of a young dog and the clucking of turkeys'". At the loudest part of the song, the bird has its neck bent so its head is touching its back. Both members of a pair as well as young down to the age of two weeks sing; often one member of a family starts a song
Red-legged seriema just as another finishes, or two sing simultaneously. The song can be heard several kilometres away; in Emas National Park, Brazil, in 1981–1982, observers often heard four red-legged seriemas or groups singing at once. The full song consists of three sections: The red-legged seriema prefers grassland habitat to any other. Though it likes to inhabit lush meadows near rivers, it will not readily move into wetlands or crop fields. It is usually seen singly or in pairs, but sometimes in groups up to four, apparently families. It typically walks on the ground and can easily run faster than a human