The Resplendent Quetzal was considered divine, says Wikipedia. It was associated with the "snake god", Quetzalcoatl, by Pre-Columbian Mesoamerican civilizations.
Their iridescent green tail feathers, symbols for spring plant growth, were venerated by the ancient Aztecs and Maya, who viewed the quetzal as the "god of the air" and as a symbol of goodness and light.
Mesoamerican (Central America; "meso" means "middle of") rulers and some nobility of other ranks wore headdresses made from quetzal feathers, symbolically connecting them to Quetzalcoatl. Since it was a crime to kill a quetzal, the bird was simply captured, its long tail feathers plucked, and was set free. Quetzalcoatl was the creator god and god of wind, often depicted with grey hair. In several Mesoamerican languages, the term for quetzal can also mean precious, sacred, or erected.