[mou] Eurasian Wigeon is a hybrid: details

[Chu, Philip]

As previously posted by Tony Hertzel, the Eurasian Wigeon at Hyland Lake =
in Bloomington is not "pure-blooded," but instead appears to have both =
Eurasian Wigeon and American Wigeon genes.

The above assertion is based primarily on three characteristics, which I =
noted while I was Hyland Lake between 4:00 and 5:00 this afternoon.
(1) On the head, although a broad postocular area is reddish brown, the =
cheeks - the region below the postocular area - and the lores are much =
duller, a pale brown-gray, with fine dark flecking.  Thus, the face is =
patterned similarly to that of a male American Wigeon, but with the =
American's shiny green postocular stripe being replaced with red-brown, =
and with the rest of the face having a weak brown tinge that the =
American's face lacks.  (In a "pure" Eurasian, the head, forehead =
excepted, should be Redhead red.)
(2) On the body, brown-pink color is not restricted to the breast, but =
mixes extensively with the gray of the flanks, especially near the =
waterline.  (In a Eurasian, the flanks should be plain gray, without any =
pinkish or brownish.)
(3) As for the bill, there is a narrow black line along the sides of the =
bill where the bill joins the head, with the black "petering out" =
dorsally so that there is no black at the base of the culmen.  This =
condition is intermediate between an American Wigeon (which has a narrow =
black line at the bill-base that runs continuously from one side of the =
bill across the culmen to the other side of the bill) and a Eurasian =
(which has no black line at the bill-base).

Shucks!  I thought that a trip to Hyland Lake might provide a sort of =
consolation prize for my inability to chase the Black Vulture on Sunday =
morning, but I guess that consolation will have to wait for another day.

Phil Chu
Department of Biology
St. John's University
Collegeville, MN 56321