The plain chachalaca (Ortalis vetula) is a large bird in the chachalaca, guan and curassow family Cracidae. It breeds in tropical and subtropical environments from mezquital thickets in the Rio Grande Valley in southernmost Texas, United States to northernmost Costa Rica. In Central America, this species occurs in the Pacific lowlands from Chiapas, Mexico to northern Nicaragua and as a separate population in Costa Rica, where its range is separated by a short distance, as a disjunct population.
This species frequents dry and moist forests, especially where interspersed with scrub and savanna. Usually found in groups of up to 15 birds, the plain chachalaca is furtive and wary and prefers to escape from danger by running swiftly on the ground or leaping and gliding through brushy tangles. The plain chachalaca feeds in trees or on the ground on fruit (figs, palms, Sapotaceae), seeds, leaves, and flowers. It is sometimes a pest of crops such as tomatoes and cucumbers.
The call is a loud, raucous RAW-pa-haw or cha-cha-LAW-ka, often by several birds in a rhythmical chorus, especially in early morning and evening, usually from well up in trees. It also produces peeping whistles and cackles. Others describe chachalaca calls as irritating noises mimicking a bunch of men arguing. The plain chachalaca typically breeds in the early wet season. The nest is a shallow saucer of twigs and plant fibers, lined with leaves, in thick vegetation. The clutch is 2–4 rough-shelled white to cream eggs.