Chachalacas
Chachalacas, curassows, and guans are 42 species of birds that make up the family Cracidae. These birds are in the order Galliformes, which also includes the grouse, pheasants, quail, guinea fowl, and turkey. Curassows, chachalacas, and guans (or cracids) are believed to represent a relatively ancient and primitive lineage within this order. Fossil members of this family are known from deposits in Europe, but modern birds only occur in the Americas, ranging from the lower Rio Grande Valley of south Texas to Paraguay and northern Argentina.
The cracids are relatively large birds, ranging in body weight from about 1 lb (0.5 kg) for chachalacas to as much as 10.5 lb (4.8 kg) in the great curassow (Crax rubra). These birds have large, bare legs and large feet, well adapted for running and scratching for food in the forest floor. Cracids have a long tail, and a fowl-like body and head. The coloration of the plumage of cracids is generally a relatively plain brown or black, with little patterning. However, many species have colorful wattles and bare skin about the face, likely important in species recognition and courtship.
Most species of cracids occur in dense forests and thickets, although some species occur in more open forests. The curassows and guans mostly feed on the ground on fruits, seeds, and other plant materials, as well as insects, but guans mostly feed in the canopy. When disturbed, the ground-feeding birds typically fly up into the forest canopy. Cracids are not migratory, spending the entire year in a local environment.
Cracids build a simple nest of sticks, located on a tree branch. The clutch is two to five eggs, which are incubated by the female. The young are able to walk and run soon after birth, and are tended only by the female.
The chachalaca (Ortalis vetula) is the only species in North America, breeding in woodlands and thickets in extreme southeastern Texas and eastern Mexico. Like many other birds, this species is named after the sound that it makes.
All of the 10 species of chachalacas are in the genus Ortalis. The 20 species of guans occur in the genera Pipile, Aburria, Chamaepetes, and Oreophasis. The 13 species of curassows are in the genera Pauxi, Mitu, Crax, and Nothocrax.
Bill Freedman
Additional topics
Science EncyclopediaScience & Philosophy: Categorical judgement to Chimaera