I found these ducks in the Fishing Pond on the west side of Gilbert Water ranch. At first glance they all appeared to be Ring-necked ducks but as I looked closer I realized they were not all the same. The black and silver ducks with the white rings around their bills and the white “spur” on their flanks are the male ring-necked ducks. The brown ducks with the white eye ring and the white patch at the base of the bill are the female Ring-necked Ducks, but just look at that male duck 2nd from the right. He looks a bit different, doesn’t he?
The black and silver male on the left is the Ring-necked duck, the black and silver duck on the right it the Lesser Scaup. Both species are diving ducks, which means they dive beneath the water for food, unlike the more familiar mallards, which are dabbling ducks that paddle about in shallow water to feed. Notice how the ring-necked duck has the black continuing along his back while the scaup is silver there. Also, the scaup has a solid blue-gray bill while the Ring-necked duck has a blue bill ringed with white. The brown ring around the neck for which the bird is actually named is rarely visible. But what caught my eye at first was the shape of the heads. I noticed that the scaup’s head was a different shape before I noticed anything else. It is what made me start to look at other details of the ducks.
Once I realized this duck was a scaup, I then had to decide if it was the Greater or Lesser Scaup. Yes, bird identification is not easy! The Greater and Lesser scaup have pretty much the same plumage pattern and to differentiate between the two one must look at the shape of the head, the sheen on the head feathers, and the nail on the tip of the beak. The Greater scaup has a steeper forehead and a higher peak in the front of the head that slopes off towards the back. the Lesser’s head is higher at the back of the skull. The Greater Scaup has a greenish sheen to its feathers while the lesser has a purple sheen. To me this photo does not show the head shape of the Lesser as well. this head shape actually looks more rectangular to me but everything else about this bird points to Lesser Scaup, including the fact that the Greater Scaup is whiter along the sides than the Lesser.
One of the things the bird guides point out is that the nail on the beak of the Lesser scaup is straight while the nail on the beak of the Greater Scaup flares out at the tip. In the photo above the nail appears to be straight to me. Greater scaup favor the coast while lesser scaup are more often seen inland in winter. But, Greater Scaup have been seen in Arizona before.
Finding these ducks provided a fun challenge to the end of our day of birding at Gilbert Water Ranch. I have never birded the Fishing Pond before and found it a great place to get close to the birds. This was only my third time birding this preserve which is also know as the Riparian Preserve at Gilbert Water Ranch. If you are ever in Phoenix I would highly recommend this place as a premier birding location in all seasons, but in the summer I would recommend getting there very early as it gets very hot very fast!
(Seen in the scrub near the Fishing Pond.)