Abstract
The avian family Cracidae is generally recognized as being comprised of two basic groups, one consisting of g uans and chachalacas, the other containing curassows. Taxonomists further separate the latter group into three or four genera. The genus Crax is composed of seven species, all of which possess bushy crests. Pauxi contains the two helmeted varieties while Mitu, the razor-bills, entails three species. The fourth (not recognized by some as a separate genus), Nothocrax, consists of one species, the Nocturnal Curassow.
Cracids are essentially medium to large gallinaceous birds that inhabit tropical forests from Mexico to central South America. Recently, however, the deforestation in underdeveloped countries has placed noticeable pressures upon the natural cracid populations. These agricultural and industrial movements, plus the constant hunting pressures by locals, have put the curassow in a rather precarious situation. Since time appears to be of the essence, it is important that an effort be made to establish and maintain viable captive breeding populations of the various cracid species. Although domestication of these birds was attempted and failed, it is still possible to rear a few birds each year from a good breeding pair. Therefore, further attention by the aviculturist is necessary, if this goal is to be attained.
For the past 22 years, the author has been fortunate enough to possess nine species of curassow and has successfully propagated seven of these, totalling over 300 progeny. The following techniques have proven effective in the propagation of these birds.
The cracid aviaries vary from 10 to 12 feet in height. Even though these birds are perchers and feel more at ease when off the ground, these heights seem adequate. Ground space dimensions range in size from 10 x 20 feet to 16 x 36 feet. All of the aviaries are of wood frame construction with 1" wire poultry netting stretched over the frames. Various types of trees are planted in each aviary and they are allowed to grow through the wire top, thus forming a canopy. These trees include: Vitex (Vitex agnuscastus), Mimosa (Albizia julibrissin), Mulberry (Morus alba), Brazilian Pepper (Scbinus terebinthi folius), California Pepper (Schinus molle), and fruit trees, such as apricot, plum, peach, quince and fig. Natural vegetation is the only form of shelter available since the southern Arizona climate seldom falls below freezing. The floor of each unit is composed of natural soil that is cultivated each fall and replanted with a mixture of rye grass, oats and barley. This provides available greens on which the birds can graze from October through June. Although curassows are not heavy grazers, they will occasionally do so, and I feel that the presence of grass is beneficial as it attracts insects which are readily eaten. The area in which the aviaries are located is also flooded to a depth of 8'' every two weeks during the summer and once a month during the winter. This periodic flooding helps reduce the number of disease-causing agents by leaching the contaminants into the soil.
The sex ratio per aviary is one male to one to four females. Each enclosure is equipped with two to four nesting sites, depending upon the number of females. The nests consist of boxes constructed of 1" x 12" lumber. Their dimensions are 24" square by 12'' deep. Smaller boxes 8 x 6 x 6 inches deep are used for guans and chachalacas. Other materials such as wicker baskets and wash tubs have been tried, but the birds seem to prefer wooden boxes. The nest boxes are positioned at various heights in the trees and along limbs that are used for perching. Experience has shown that the highest nest is the most often used. Nesting materials consist of leaves and straw.
Shortly after the eggs are laid, they are collected and placed under a broody chicken hen of sufficient size. It has been the author's experience that fertility and hatchability decrease more rapidly in curassow eggs than in most others. Since the normal clutch size consists of two eggs, it is imperative that incubation commence within one to two days of the laying date. The incubation period lasts 29 to 32 days and the chicks can usually be heard within the shell three days before hatching. Pipping usually begins at one spot, and this area will remain broken for approximately 12 to 24 hours. When the chick turns in the shell and the actual hatching begins, it takes no longer than two to three hours for the chick to emerge.