Unusually known as Mandarins, the dazzling Mandarin Duck (Aix Galericulata) are slightly over a pound, males are best known for their strange orange-chestnut “side whiskers” and curious dorsal orange-gold “sails” that extend up along the flanks. The greatly enlarged inner vane of the modified twelfth secondary feather is responsible for the conspicuous sail. The peculiar feathers are not held erect in flight as sometimes depicted, but rather are flattened against the body. Despite a remarkable similarity to female American Wood Ducks (Aix Sponsa), hens are paler overall, with more greenish speculums. The white surrounding their eye is restricted to thin eye-rings, with a very narrow white line extending back toward the nape. While Mandarins (Aix Galericulata) frequent valleys up to 5,000 feet, these primarily lowland ducks prefer small islands and bodies of water that support abundant emergent vegetation. Most active during the pre-dawn and twilight hours, a major portion of the day is spent loafing under hanging branches and trunks. Relatively shy and secretive in continental Asia, the ducks readily adapt to close human presence when undisturbed. Courtship displays are highly synchronized, and mated pairs are inclined to preen mutually. Mandarins (Aix Galericulata) commonly display communally in the early morning and at dusk when the light is dim, or the dense shade of overhanging trees, possibly because the brightly colored drakes are less conspicuous to predators. The exceedingly showy males stand or swim with the head drawn well back, chest expanded, large bushy crest erected, “side-whiskers” puffed out, and the unique ornamental tertial “sails” elevated to full extend. When their mates are incubating, males can be promiscuous, with bigamous drakes sometimes establishing loose pair bonds with second females. Nest are normally located in tree holes as high as 50 feet, as well as in stumps, fallen logs or roots, and rarely on the ground beneath bushes or logs. During the fall and winter, Mandarin Ducks (Aix Galericulata) are drawn to rice fields, mashes and more open rivers, although estuaries or brackish lagoons are rarely utilized.