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Some may have wondered where the bird was in May's quiz photo, though most respondents not only found the bird, but identified it correctly. In the right half of the picture, there is a blob protruding from the water that sports a combination of colors: blackish, gray-brown, perhaps bluish-gray, and whitish. That is the bird. Or, at least, the part of the bird visible in the picture. This bird might have been almost any waterbird that can submerge in water – on its way up or down, but perhaps there's another reason that we can see only a small fraction of the beast. But, let's see what we can do with what we have.
We'll start with the setting – apparently a pond with edge emergent and edge vegetation. This habitat certainly suggests against any of the true seabirds. Moving to the bird, itself, we can see a large dark circular bit that seems to be an eye. The darkness of it actually enables us to eliminate all sorts of diving birds from consideration, such as most cormorants, many ducks, the loons, and most grebes – there are a lot of red, yellow, and blue eyes amongst diving birds for some reason. Granted, many immatures of some of these groups sport dark eyes, but eye color can still help us out quite a bit. Additionally, our quiz bird seems to have at least a partial eye ring of some near-white color.
The shape of the head and the position of the two eyes suggest that the bird is facing us, thus the varicolored protuberance between and in front of the eyes must be the bill. Interestingly, the bill seems to be tri-colored with a pale base, a blackish vertical bar, and a pale tip that is a bit darker than the base. Well, vertical black bars on bills are quite rare on ABA-area birds and I think that everyone would be comfortable at ruling out Ring-billed Gull – particularly as when that species has a ring on the bill, it also has yellow eyes. Having ruled out various coots previously by eye color and by our bird's seemingly partial eye ring, we're left with only one real possibility: Pied-billed Grebe.
Ah, now we can understand my comment in the first paragraph. While most diving birds control their depth in the water quite actively – using wings and/or feet – the Pied-billed Grebes are masters of buoyancy, being able to alter their relative density almost passively. By pressing air out of their feathers and by moving air in or out of internal air sacs, they have very fine control of their buoyancy and can hold as much or as little of their body (up to a point at the upper end) above the surface as they wish. For a species that often finds itself on small bodies of water – such as the one in the picture – being able to essentially hide while still keeping an eye out for danger enables the specie to utilize water bodies that many other diving birds cannot.
I took this picture of an alternate-plumaged Pied-billed Grebe at Villas W.M.A., Cape May Co., NJ, on 5 April 2009.
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The following people (listed by submission date beginning with the earliest) submitted correct answers for the May Bird Photo Quiz—Pied-billed Grebe:
As stated in the quiz rules, answers must consist simply of the Common or English name exactly as it appears in the ABA Checklist.
The following list shows the number of submissions for each species guessed.
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The photo and answer for this quiz were supplied by Tony Leukering.