Ferruginous Duck Aythya nyroca
One adult male watched (and videoed) on several dates on Dongpan, Joonam reservoirs, Kyeongsangnam Province, between February 2nd and February 11th 2002, when it was seen associating very closely with (and even displaying to) a female Baer’s Pochard Aythya baeri (see image above). Not present on February 14th when searched for.
Seen very well by Nial Moores (who has previous experience of the species in the UK, Spain and Japan), and by Kim Su-Kyung and two student bird researchers on February 2nd; and also by Charles Moores (who is experienced with the species in Europe and South Asia) on February 10th and 11th. Identified simply by its (1) combination of rich reddish-brown head and flanks, and contrastingly darker upperparts; (2) clean white (framed darker) undertail coverts, and (3) whitish eye. (4) The bill was also largely dark grey, with a paler subterminal band and small black nail, ruling out any hybrid origins. In addition, (5) the head shape was typical for Ferruginous Duck, with a peaked crown and significantly less sloped forehead than found in the rather similar and closely-related Baer’s Pochard.
Though considered a species of global Special Conservation Concern (anon 2001), with only three sites given in the Asian Waterfowl Census 1987-1991 in eastern China and northern Taiwan (Perennou et al 1994), the Ferruginous Duck is actually very scarce but regular in Hebei, with seemingly good numbers still in western China (J. Hornskov pers comm). The species is much scarcer further east, but it has been recorded at least twice in Japan, with one recorded in Chiba Prefecture in 1959 (Brazil 1991), and another male returning for several years to the same park in Fukuoka City, Fukuoka Prefecture, Kyushu in the early 1990s (Kirihara, Yamagata & Toshiyuki, 2000; pers obs). As such it can perhaps be expected to occur irregularly in South Korea in mid-winter.