tapirage
n.— «Macaws and other parrots supplied most of the plumage, but that of other species—Muscovy ducks, flamingos, egrets and the petite paradise tanager—was also prized. Some colors were produced artificially in a process known as tapirage. Birds with, say, green and blue feathers were plucked and then rubbed with frog secretions; the feathers would then grow back in an unnatural yellow-orange hue.» —“Objects From a Long-Vanished Peru, Parading All Their Magnificent Plumage” by Karen Rosenberg New York Times July 5, 2008. (source: Double-Tongued Dictionary)