mjm@oliven.olivetti.com (Michael Mammoser) (11/07/89)
Some weeks ago I made a posting concerning the observation of three Eurasian Wigeons in the same day here in the San Francisco Bay Area, remarking about the various stages of molt that they were in. I incorrectly stated that this was a molt sequence from juvenile plumage into adult. After doing some research, I discovered that these birds were actually molting out of eclipse plumage. It seems that the juvenile birds look a lot like a female. The juvenile males molt from this plumage (during the fall of their first year) into a near-adult plumage; with the exception that the forewing patch is a mottled, dingy gray (like the female) instead of the pure white patch of the adult male. In the second year these immature males attain the eclipse plumage (while retaining the immature wing); and only after molting out of this eclipse plumage do they reach full adult plumage. So the birds that I observed must have been either adult males or second year males (I didn't note the forewing patch) rather than juveniles. I assume that there must be some juveniles or females in the area; although the task of identifying them from female American Wigeons probably leaves them as invisible as if they weren't there. I'm sorry about the misleading statement in my previous posting. Mike