This month’s quiz-photo is another in a long history of bird-identification photo quizzes that encourage not only selecting a species for which critical characters of the subject match those known for the suspected species, but also studying those characters that rule out similar species. To put it more bluntly, just because a bird has a red eye, does not necessarily mean that it is a Red-eyed Vireo!
This quiz’s subject has a stout, medium-length bill and an obvious white wing stripe, and nearly all respondents got to the shorebirds for a solution. The aforementioned combination of characters rapidly reduces the number of options in the ABA area to just three species: American and Eurasian oystercatchers and Willet. Two each of turnstone and godwit species are ruled out by our subject’s bill length: too long for the former, too short for the latter. The apparently blackish head and chest should rule out Willet and the fact that the white of the rump does not continue up the back rules out the mega-rarity, Eurasian Oystercatcher, so this must be an American Oystercatcher. Right?
Well, let’s back up a step. Is the head black? If this were one of the white-bellied oystercatcher species, then it should have a white belly, not the apparently dark belly that this bird sports. Hmm. If this bird does have a dark belly and a white wing stripe and if it were an oystercatcher, then it would have to be a hybrid American x Black Oystercatcher, which can be found with some regularity in the San Diego, CA, area. However, the online ABA quizzes do not allow for hybrids, so this must be a full species, thus it cannot be an oystercatcher. In fact, upon closer scrutiny of the bird’s left wing, we can see distinct contrast between the black primary coverts and the brownish secondary coverts, a feature not present on any ABA-area oystercatcher, but typical of the only species remaining in the quiz’s solution set.

I took this poorly lit picture of an adult eastern Willet at Rio Grande, Cape May Co., NJ, on 5 June 2012.
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The following people (listed by submission date beginning with the earliest) submitted correct answers for the December Bird Photo Quiz—Willet:
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.