Quiz #400 (2011-2-08) Solution

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Solution by Tony Leukering

Three individuals this time, with at least two species present: a woodpecker and a thrasher. Or two thrashers. As at least one respondent noted, identifying the "easier" bird -- the woodpecker, may help us ID the thrashers, so let's head down that road. The woodpecker is one of the zebra-striped beasts, but one with an odd tail pattern, a feature that some may have noted as critical. That pattern includes a mix of entirely black feathers and black-barred white feathers. While we might consider female Williamson's Sapsucker, that species doesn't sport quite the regular black-and-white barring exhibited by the quiz woodpecker. Additionally, they usually sport a vague superciliary and always have dark flanks (unlike our bird's paler flank). Additionally, the quiz woodpecker has the central rectrices barred, not solidly black, as in Willy Sap. In fact, that pattern of all-black middle rects on each side but with all other rectrices barred also rules out Golden-fronted Woodpecker, which has an all-black tail except for the barred outermost rectrices. Red-bellied Woodpecker has a similar tail pattern to that of our quiz bird, but that species sports some red or orange on the head in all plumages -- something that our quiz woodpecker lacks.

So, does an ID of Gila Woodpecker help us with the thrashers? In that vein, the various species that might jump out at us as good possibilities all are sympatric with Gila Woodpecker. Ah, well. Both thrashers have longish and obvious curvature to their bills, ruling out Sage Thasher immediately and, with consideration of photographic angle, Bendire's Thrasher. Yes, the left thrasher's bill may look shorter than that of the right thrasher, but, the left one is facing at least somewhat toward us, so its bill is foreshortened. Despite that, we can see the distinct kink in the bill, compared to the short and evenly-curved bill of Bendire's Thrasher.

The really streaked thrashers are right out for both thrashers and the left one cannot be either California or Le Conte's, because it sports a pale eye. Crissal Thrasher is ruled out for that species as well, for a number of reasons, one of which is that the bird lacks distinct and black lateral throat stripes and another is that it lacks an obviously red crissum. The vague grayish-brown spotting heaviest on the chest and with a vaguely paler belly than chest suggest that this bird is referable to palmeri Curve-billed Thrasher (the western form). With those features in mind, glancing back at the right thrasher should point us in the same direction. While we might have considered Crissal for that one (we cannot see either its eye or vent colors), that vague spotting underneath rules that option out, as does the brown aspect to the underparts coloration (rather than the medium gray of Crissal).

One last note about Curve-billed Thrasher: the two ABA-area subspecies are usually separable by plumage and have differing vocalizations and the species is a good candidate for splitting. Thus, it behooves us all -- particularly those looking at out-of-range Curve-bills -- to pay attention to which is which. I took this picture of a female Gila Woodpecker and a pair of Curve-billed Thrashers at the San Xavier Mission, Pima Co., AZ, in January 2007.

One respondent submitted an answer with only one species. Also, one respondent neglected to capitalize the 't' in 'Thrasher.'

Incorrect species provided as answers:
Crissal Thrasher - 1
Bendire's Thrasher - 3
Williamson's Sapsucker - 3

Congratulations to the 17 of 25 getting the quiz correct:
Kirk Huffstater
Christian Nunes
Margie Joy
Pam Myers
Nick Komar
Robert McNab
Peter Wilkinson
Barbara Deneen
David Such
Chishun Kwong
Christopher Hinkle
Diane Porter
Marcel Such
Adrian Hinkle
Joel Such
Bryan Guarente
Burke Angstman

Answer: Gila Woodpecker, Curve-billed Thrasher

Quiz #399 (2011-2-07) Solution

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Solution by Tony Leukering

This week's quiz bird was considered, without exception, to be a member of the small sparrow genus Melospiza by the week's respondents, who covered all the bases and provided all three species as answers. Of course, unless the bird is a hybrid, only one species can be correct, but the trick is how to tease that correct answer out of the fairly minimal -- though eminently typical -- view of a bird of a fairly retiring genus.

First off, even ignoring the apparently dense habitat in which our quiz bird is perched, we can quickly determine that the species is a denizen of thickly-vegetated habitats by looking at the wingtip visible. It is obviously quite rounded, with the four longest primaries being all nearly the same length. This is a typical feature of species that would prefer not to wear away their primary tips by beating them against the leaves and stems so prevalent in dense habitats. In case we were considering them, that fact can rule out longspurs for us.

If we can prove that the bird is not in juvenal (= first basic) plumage, then we can rule out Swamp Sparrow with its minimal streaking and strongly rufescent flanks. However, the softness of the focus on the quiz bird (the camera obviously considered the alder leaves to be the picture's subject) makes it difficult to discern the structure of the undertail coverts feathers, which would be soft and much more barbless than those of older birds, though I would still lean toward those feathers not being juvenal feathers. However, there is another way to determine the bird's age, even more generally than juvenal plumage vs. all other plumages. In Melospiza, individuals that are less than 14 months old and haven't completed their 2nd prebasic molt have a green cast to the gray on the head. It is weaker or stronger among individuals, but it is always present. Our bird lacks that green cast or tinge; its superciliary and cheek are smoothly gray. Another feature can confirm our decision to eliminate Swamp Sparrow from consideration, and that is the back. On Swamp Sparrow, the black streaking is so wide that it implies a dark back with paler streaking, unlike our bird's palish back with dark streaking.

Now things get really tricky, as much of the plumage often considered critical for separating Song and Lincoln's sparrows is behind those well-focused alder leaves: the malar region and the chest. But, as is often the case in the CFO Photo Quiz, I am very much interested in those features that are not used by most birders to ID birds, but which still provide perfectly useful ID information. And at this point, I want to point out that most of the benefit that I get out of conducting this quiz (I am a volunteer, just as all of CFO's principals are) is when it becomes obvious that I have had an impact on even one birder's understanding and knowledge. This week, Burke Angstman provided that hit of gratification to me with the following:

"Since I'm new to the CFO Photo Quiz I have been reviewing some of the previous quizzes and what I was able to find was an excellent photo of a Lincoln's Sparrow taken by Rachel Hopper and presented by you in Quiz #308. (This was really one of the best photos of a Lincoln 's Sparrow I was able to find.) Your description of the Lincoln's Sparrow included this statement:

'But, the color of the streaking on the undertail coverts (and on the flanks) is black, not the reddish color of morphna or most other races of Song Sparrow.'"

Indeed, Burke hit on the very feature that I planned on using to explain why this week's quiz bird was a Song Sparrow, rather than a Lincoln's Sparrow. The photographer, Terry Gray, reeled off four quick pictures of the subject in Latah Co., Idaho, on 9 October 2010, in the possibility that it was a late Lincoln's Sparrow. This photo, which was really the only useable one, came to me when Terry was searching for assistance in the bird's ID and I immediately recognized the photo-quiz potential of the picture. Because, as the long-time participants of this quiz know, I like to throw in difficult pictures of very common species. That is because, to really excel in identification, one really does need to know the common birds cold! Thanks, Burke!

With the devastation wreaked on the leader board by this quiz photo, Christopher Hinkle emerged as the sole respondent with a perfect score for the quarter.

Incorrect species provided as answers:
Lincoln's Sparrow - 13
Swamp Sparrow - 2

Congratulations to the 7 of 22 getting the quiz correct:
Margie Joy
Su Snyder
Burke Angstman
Adrian Hinkle
Christopher Hinkle
Chishun Kwong
Nick Komar

Answer: Song Sparrow