Formerly known as "Falcated Teal" the male sports spectacular elongated sickle-shaped (falcate) scapulars which hang over the tail often with their tips touching the water as seen here. The head is a variable mix of iridescent green and purple. Depending on the light, the purple may appear a copper color. This spectacular and distinctive duck is primarily a winter visitor to Honshu although it breeds in parts of Hokkaido. Formerly abundant, this species has declined in recent decades. It is classified as "near threatened," the main threat being overhunting in China. Originally placed in the genus Anas it has been moved to Mareca with the Wigeons and Gadwall. This change was recommended in a genetic study by González et al. (2009) who found Anas was otherwise polyphyletic. Canon PowerShot SX60.
References:
BirdLife International (2019) Species factsheet: Mareca falcata. Downloaded from http://www.birdlife.org on 09/04/2019.
Brazil, M.A. (1991) The Birds of Japan, Smithsonian Inst. Press, Washington DC.
Carboneras, C. & Kirwan, G.M. (2019). Falcated Duck (Mareca falcata). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from https://www.hbw.com/node/52865 on 5 April 2019).
González, J., H. Düttmann, and M. Wink (2009). Phylogenetic relationships based on two mitochondrial genes and hybridization patterns in Anatidae. Journal of Zoology 279 (3):310-318.