Monday, January 23, 2012

Quiz #434 (2012-1-04) Solution


Click on picture(s) for a larger view.

Solution by Tony Leukering

I know when a particular quiz photo is tricky when there is a large variety of species posited incorrectly as the solution to the quiz. This week's quiz was even trickier, as only one of the six incorrect species submitted received more than one vote, so to speak. One respondent submitted "sparrow sp." which, in a way, is correct, more so than some of the incorrect responses, but the bird is certainly identifiable.

This month’s quiz picture presents a bird hiding in a fruiting Multiflora Rose (Rosa multiflora), an Asian species introduced to the New World and now an invasive pest. For any such species of bird-food-providing plant, it behooves us in quizzes such as this to know the fruiting times, as that gives us at least an indication of photography date, which can help us in the identification process. As for most roses, the hips on Multiflora Rose are produced in late summer/fall, ripening in mid- to late fall. As there seem to be so many hips – that is, birds haven’t, yet, decimated the larder, it is probably safe to say that the quiz picture was taken sometime in the mid-fall-to-early-winter time period.

Those birders that play – or, at least look at – more than one online photo quiz may have noticed that this picture and the picture in the January 2012 American Birding Association’s online photo quiz are remarkably similar. In fact, these two pictures are of the same individual taken just seconds apart, thus they could be used in concert to identify the bird in question.

Looking at the CFO quiz picture, we have a bird facing away that has a brown head, back, and tail; brownish-orange side; and pink legs. A minority of bird species have pink legs, but a large proportion of those are members of the Emberizidae, the family housing the New World sparrows. With the foot structure visible – particularly the long nails on the hind toes, we can be fairly certain that this bird is such a one, and the plumage that we can see, confirms that supposition. Once in the Emberizidae, the underparts color and pattern quickly take us to two species, both of which were formerly lumped in an entity known as “Rufous-sided Towhee.” However, once there, things get just a wee bit tricky, primarily due to the variability of plumage inherent in the numerous subspecies of one of the species making up Rufous-sided Towhee.

Separating Eastern and Spotted towhees is often quite straightforward, but there are some major pitfalls. The first of these is hybridization where the two species meet in the Great Plains, with the local form of Spotted Towhee (arcticus) having at least a few Eastern-like traits that are otherwise not found in Spotted Towhee. The other is the form of Spotted Towhee breeding in the Pacific Northwest that nearly lacks the spotting that is the source of the species’ name (such as that illustrated in CFO Photo Quiz #337). Knowing where the bird was could help tremendously, but that information was not provided with the quiz pic, so we’ll have to move on without that datum.

There are no indications of pale spotting on the scapulars and wing coverts on the quiz bird, so this might very well be an Eastern Towhee, as suggested by the bird’s brown head and back. Though arcticus females do have brownish upperparts, that form is also very strongly spotted with white there, so it must be an Eastern Towhee. Unless it's a hybrid. What we can be certain of is that the bird sports the white “handkerchief” (the patch of white at the base of the primaries) typical of Eastern Towhee, but not found in any pure Spotted Towhee. (The other bit of white on the primaries is typical of both members of the “Rufous-sided Towhee” species complex, and is variable in appearance in all individuals.) By checking out the ABA quiz picture (noted above), we can see that the handkerchief is certainly as large and obvious as we'd want in a good Eastern Towhee. Finally, and unrelated to the species’ identity, the eye color is a slightly orange shade of brown, which indicates the bird’s age.

I took this picture of an immature female Eastern Towhee at Cox Hall Creek WMA, Cape May Co., NJ, on 12 November 2011.

Incorrect species provided as answers:
Eastern Bluebird - 1
Black-headed Grosbeak - 1
Rufous-backed Robin - 1
Swamp Sparrow - 1
Brambling - 1
Dark-eyed Junco - 3
Eurasian Tree Sparrow - 1
sparrow sp. - 1

Congratulations to the 14 of 24 getting the quiz correct:
Tyler Bell
Ben Coulter
Kirk Huffstater
Nick Komar
Logan Kahle
Peter Wilkinson
Christian Nunes
Pam Myers
George Cresswell
Su Snyder
Robert McNab
Devich Farbotnik
Diane Porter
Aaron Brees

Answer: Eastern Towhee