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Wednesday, January 26, 2011

Murky Waters: the case of the mystery Mallard!

Januray 25, 2011 12:30-1:30pm 10` cloudy Turner Reservoir East Providence RI

A thick layer of ice coated Turner Reservoir and the ground was covered with a heavy layering of whiteness making this winter wonderland look like a chef had gone over board with white icing (in truth this was as far from reality as you could get, as you very likely guessed it was just another snowy day!)

Today Turner was fairly uneventful; a Red-bellied Woodpecker here, some Tufted Titmice there and so on. The only excitements discovered were what I suspected was a Northern Flicker calling somewhere off in the woodlands and a bird feeder in a local backyard which had attracted a mass of House Sparrows, a White-throated Sparrow and a Northern Cardinal.

The Ten Mile River flows under the frozen Turner Reservoir, there is a dam at one end of the reservoir, over the dam water rushes and pours down 15 feet to the Ten Mile River which winds away into the woodlands. Here the water is open and Common Mergansers swim cheerfully about. When we had started our walk I thought I had seen a Ring-necked Duck with those Common Mergansers. So when we returned to our car we decided to split up, my mother and sisters going to the car to warm up and my brother and I continuing down the trail a little way more to see if we could find the Ring-necked Duck for a positive id.

We found a few birds other than mergansers and a Great Blue Heron who took off when we appeared on the river bank. Then as we clambered through the bushes trying to get a good luck at the water I noticed a pair of Mallards a male and what appeared to be a female. Suddenly I realized that the "female" had a greenish tinge to the head and a male's black and white tail with curved tail feathers to boot!

Every summer males molt loosing their green, chestnut and silver feathers for the more modest colors of a female (this is called an eclipse plumage). They then molt the eclipse plumage in fall for their bright breeding colors. The dull-colored eclipse Mallard as well as the breeding male and the juvenille Mallards all have a yellow or olive bill. This unusual Mallard had the orange blotched with black coloring particular to only a female bill. Funny bill, funny tail, funny head coloring. All in all it is one crazy Mallard!

The only conclusion that I could come to is that it is a gynandromorph which in more understandable terms means that it is both a female and male. Usually one side of a gynandromorph bird has female plumage while the other side has male plumage. Seeing that we could only see one side of the bird we can't be sure that on the other side there is the male plumage but I doubt that there is.

I have only found one reference to a gynandromorph Mallard and that was on a Seirra Nevada bird alert where the author (Will Richardson) writes as follows

"Cove East and the Upper Truckee Marsh were LOADED with Mallards!! The area of the Upper Truckee Marsh closest to the Cove East parking has
several inches of water on it, and the ducks are loving it! A few
pintail, but mostly just tons of Mallards, including an interesting
gynandromorph that looks really similar to one I photographed there a
few years ago. Same bird? "

Frustratingly he didn't leave a photo of the bird or any description.

The only photos of a gynandromorph bird that I could find was of a Northern Cardinal from Illinois. The birder also wrote about what a gynandromorph is on his blog, it is very interesting allbeit confusing. You can check it out here . Here is another link to his blog where he shows photos of the bird.

It would be great if it really is a gynandrmorph and a very unusual find.
I would greatly appreciate any help you could give.

ps I found the Ring-necked Duck in the end (a year bird)!

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