Greater Scaup, Aythya marila
Greater Scaup, male, 3/25/05, Palo Alto Baylands
Greater Scaup, male, 2/4/08, Palo Alto Baylands
Greater Scaup, female, 3/3/08, Shoreline Park, Mountain View
Greater Scaup, female, 3/25/05, Palo Alto Baylands
The head is more rounded, the nail at the tip of the bill is about twice as broad, the base of the bill is deeper, and (sometimes) the iridiscent head of the male is green as opposed to purple -- distinctions from the Lesser Scaup. The Palo Alto Baylands duck pond is one of the best places to see both species close up. Males at the top, females below.
Greater Scaup, female, 11/20/05, Palo Alto Baylands