Monday, August 13, 2012
Solution by Tony Leukering
This week's quiz bird seems to be perched on rip rap, and since there seems to be water behind it, we might surmise that the bird is on a jetty. Of course, that assumption may or may not help us with the bird's ID; it might even send us astray. Regardless, since we can see at least one of the bird's hind toes and it is not elevated, we can rule out any shorebird. In fact, our bird appears to have a stout and short bill, dark above and yellowish below. Those features, also, rule out shorebirds, as do its short, pink legs.
The short and stout bill might send us to the back of the field guide where reside most such ABA-area birds. The plain and dull underparts, in combination with the pink legs, rule out all of the finches. The brown crown and those pink legs might then send us searching among the Emberizidae (the New World sparrows and similar things), but that plain and dingy breast doesn't fit too many options there. The brown towhees are, well, too brown, and the beastie just looks off for it to be any of the plain-breasted sparrows, perhaps because of those blackish bits on the chin and throat. Ah, that lovely, Canadian breeding endemic sparrow, Harris's, has black on the chin and throat, but it should have either a lot more black in that area (adults), or less (immatures), and, if less, ought to have some black spotting/streaking on the upper sides, which it lacks. Even though, to experienced birders, it might seem unlikely, I have seen multiple beginning birders identify those brown birds with black on chin and throat nesting in the eaves of their houses as Harris's Sparrows. That may be because they get to the New World sparrows in the field guide, find Harris's Sparrow, and stop looking. Thus, they don't find, at the very back of the book, that introduced sparrow from the Old World that also sports black chin and throat (and upper breast). While our bird does not sport much of the black typical of a male House Sparrow, we can see the rough outline of that black and be happy with that ID. What we may not know, though, is that male House Sparrows molt in new feathers on the chin, throat, and upper breast in late summer/fall (along with all of their other feathers) that have thin to wide pale fringes that obscure the black throat patch. As those feathers wear through the fall and winter, the black becomes more and more evident.
Those that studied the quiz bird more closely will have noticed that the crown looks at least partly brown, not entirely gray, and that there does not appear to be any black in front of the eyes. Ah, close scrutiny is always good when obtainable. When male House Sparrows grow their juvenal (=first basic) plumage in the nest, they grow female-like plumage. However, once fledged for a bit, they initiate their preformative molt and bring in obviously male plumage. With these facts, we can safely surmise that our quiz bird is an immature male House Sparrow somewhere in the process of replacing its juvenal plumage in its first fall, when I took the picture at Avalon, Cape May Co., NJ, on 7 October 2008. I have included, below, an enlarged crop of our quiz bird's upper body in which one can see the mix of dull, even pale, brown and gray feathering in the crown; the former being juvenal feathering, the latter adult. Amazingly, the location of the photograph was guessed by one respondent, Sean Fitzgerald. Of course, he had an unfair advantage, having spent an entire fall standing by this jetty counting the immense southward migration of waterbirds there, oddly enough, in 2008! Finally, at least as this quiz is concerned, Peter Wilkinson correctly sussed the bird's plumage and which molt it was conducting.
Now that we're a bit over halfway through the quarter's competition, Richard Witters finds himself alone atop the leader board with a perfect 7-of-7 score; seven others are on his heels with 6 correct responses. As for the annual competition, Ben Coulter (30 correct responses) has a one-correct-response lead on Robert McNab.
Incorrect species provided as answers:
none -- excellent!
Congratulations to the 21 of 21 getting the quiz correct:
William von Herff
Answer: House Sparrow