"The Copán Mosaics Project began its work in 1985 with the task of re-articulating, conserving, and studying the mosaic sculptures of Ballcourt A-III. The façade fragments were excavated by Derek Nusbaum and Gustav Stromsvik of the Carnegie Institution and carefully stacked in four discrete piles in the immediate confines of the ballcourt. There were more than 1200 ballcourt pieces, falling into a series of discrete motif categories: scarlet macaw body parts, feathered collars, akbal (darkness) signs, maize and vegetation, and vertically-tenoned 'bony ahau' pieces.
After calculating the minimum number of individual figures, and much patient experimenting and re-evaluating, Barbara Fash devised reconstructions for 16 ballcourt birds. Work with the wedge-shaped tenons of the pieces demonstrated to her that four of the birds on each building were placed on the corners, thus leaving the other four to be placed on the columns between the doorways on the east and west sides of each of the two structures. The birds are each composed of a head with open beak surrounded by a beaded collar, left and right talons placed below the collar, wings -- complete with the serpent-head symbol that is placed on bird wings in Maya art -- which extend horizontally from the sides of the collar and body, an elaborate tail assemblage including the akbal symbol, and a cascade of tail feathers bifurcating and then extending symmetrically in two courses to the left and right of the central tail assemblage.
A composite example combining the best-preserved examples of all these motifs into a single bird has been restored and placed on the eastern structure of the ballcourt, facing the playing alley, so that the visitor to Copán can get an idea of how the sculptured façade looked in its original state."
William L. Fash, Scribes, Warriors and Kings: The City of Copán and the Ancient Maya, p. 126