The above four photographs show a male 'green-winged' teal with features of both Common Teal and Green-winged Teal. The bird was found by Tom Burke, Andy Guthrie, Gail Benson and myself on Pond X in Lawrence, Nassau Co., New York in early March 2002. This phragmites fringed pond, located in a suburban neighbourhood, is generally ice-free all winter and hosts a good number of Green-winged Teal, with occasional male Common Teal reported.
This interesting male resembles a Common Teal with respect to the horizontal white bar but has a hint of the vertical bar suggestive of Green-winged Teal. The patterns of strong horizontal bar and weaker vertical bar was reproduced on both sides of the bird. The golden edging to the green facial mask seems subdued compared to other Common Teal we have seen in New York. On the rear of the bird, the narrow creamy bar separating the black semicircle from the vermiculated flanks seems slightly broader than typical for Green-winged Teal but again not as broad and obvious as we expect for Common Teal. [I apologize for the poor quality of these digital photos taken through a Kowa TSN-4 scope. The bird was rather distant and conditions were cold and extremely blustery. Numb fingers and windy conditions do not promote good digiscoping!]
For comparison, I add below a couple of shots of 'conventional' Green-winged Teal taken around the same time.
Two male Green-winged Teal, Jamaica Bay NWR late Feb. 2002. Photo copyright of Angus Wilson
Male Green-winged Teal, Floyd Bennett Field, NY early March 2002. Photo copyright of Angus Wilson