Eclipse Dabbling Ducks

In September and October each year we see a confusing array of atypical-looking ducks as they molt from eclipse (basic) plumage into the more familiar breeding plumage of winter and spring. I've found that as with passerines it helps a lot to focus first on the bill and face of the bird before checking out the rest of the bird. These photos, from Las Galinas ponds in San Rafael, are not as sharp as I would have liked, but since I learned something from each one I figured they are worth sharing.

The eclipse Cinnamon Teal drake looks a lot like the female, but the red eye gives him away. Note the Shoveler-like bill and "plain" face, i.e. no dark line through the eye.

The Eurasian Widgeon was puzzler, as its color was almost like a Cinnamon Teal, but the bill clearly said "wigeon", and it was much too red to be an American Wigeon. The female Eurasian Wigeon can often be warm in color, but never quite so warm as this drake. There is no real black border where the bill meets the face, as seen on American Wigeon. Same bird viewed 10 days later began to show some buffy color on the forecrown, and a hint of gray on the shoulder.

At times there have been up to 3,000 Northern Pintails at the ponds, but numbers down to perhaps 600. Very instructive to seem the males in every stage of molt from eclipse to breeding. The male here has the plain brown face we see in the female Pintail, but his beautifully trimmed steel blue bill gives him away. We can also see the beginning of fine vermiculations on the side of the body.

Here's another Pintail that is a bit further along in the pre-alternate molt:

The eclipse Gadwall looks a lot like the breeding male, save for the lack of vermiculation on the body. Here he's showing the cinnamon wing patch, formed by secondary coverts on the top of the wing, best seen in flight. Female and juvenile Gadwalls have some orange on the bill.

Lastly, here's a male Northern Shoveler from early September. I suppose it could be a juvenile, but the bright yellow eye is more consistent with an adult eclipse male.