Friday, September 19, 2014

American Black Duck - Anas rubripes

Soon after entering Connecticut's Hammonasset State Beach there is a pond on the right that often has good birds, and on our recent visit we watched a group of about 9 dark Mallard-type ducks foraging together. We hoped that they were American Black Ducks, Anas rubripes, as indeed they looked darker than your average Mallard. Local birders there assured me they were Black Ducks, and the olive bills suggest adult female, or maybe juveniles. We didn't see the feet well. "rubipes" = red feet, which would have helped (red-orange, actually). Here some are loafing along the shore.




A subtle mark that may be a clue that they are not Mallards if the color of the speculum, violet in the Black Duck and blue in the Mallard, but this feature can vary. This shot is a crop from the first photo:


The Mallard Complex, besides the Mallard, includes U.S. birds such as the Mexican Mallard (a subspecies), Mottled Duck, and the American Black Duck. Hybrids confuse the issue, and are especially threat to the gene pool of the Mottled Duck in Florida and the Gulf Coast. A dozen or more Anas species outside the U.S. are also considered part of the Mallard Complex. Here we see the olive bill, quite different from a Mallard's.


The Black Duck is an Eastern Species, breeding in Canada and the Northeast, with a winter range down to the Southeastern states above Florida. Their population was historicaly as high as 1,000,000, but they experienced a steady decline from hunting pressure to a level of about 300,000. Daily limits may have halted the decline, but it remains one of the main duck species taken in the northeast. Here's a better shot of the cryptic dark plumage.


You may know that I am particularly fond of ducks (easy targets, for sure), and wrote "The Duck Family", available from my Dropbox account. The download is over 200MB, so it may take a few minutes. It views very well on a tablet such as iPad, or even an iPhone. You may have to decrease the viewing size when you view it on a desktop (controls for size appear when the cursor is near the bottom of the PDF screen). Will add the Black Duck to a future edition.

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