Quiz #390 (2011-1-11) Solution

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Answer by Tony Leukering

Raise your hand if you immediately identified this week's quiz bird on posture alone. Oh, perhaps you then had second thoughts about other species that might share this bird's posture, but I will bet that for most people looking at the quiz photo, their first thoughts were correct.

The take-home message of this quiz is that structure and posture can enable us to identify a large percentage of the birds we see on any given day, if only we know them intimately, like most of us know this week's quiz bird. Without resorting to field marks. That is, a skulking smallish sparrow with a raised crest is nearly always a Lincoln's Sparrow. A long, low-slung dabbling duck with its big head pulled into its shoulders is probably a Northern Shoveler. A tiny brown ball of fluff with nearly no tail is a Winter Wren. Or, now, a Pacific Wren. A largish passerine standing on the ground with head and back erect, tail slightly cocked, and long wings drooped to below the level of the tail is nearly always an American Robin.

Yes, other species of Turdus and Wood Thrush need to be considered (or the Catharus thrushes if we got the size estimation wrong), but given where birders live and how common American Robin is in the places where most of the ABA-area's birders live, it is quite correct to jump to the conclusion that such a bird is an American Robin. While we cannot see our quiz bird's underparts, we really do not need to see them to confirm our snap ID, but we ought to look at at least a few characters to be certain. The upperparts are dark gray. Check. The rump is the palest part of the upperparts plumage. Check. The tail is black. Check. The wings are plain and dark. Check. The crown is blacker than the nape and/or the back. Check. There are white eye arcs. Check. The bill is yellow. Check. Card-carrying American Robin; no red underparts seen. Nor black-and-white-striped throat. Nor white vent. Nor white tail corners.

Now, the real trick is becoming as familiar with as many of the other species one sees as one is with American Robin (or whatever one's local easy-to-watch, abundant species is). Yes, the clues are much more subtle with some (many?) than they are with American Robin, but they are there. There to be studied and learned.

I took this picture of a (male?) American Robin at the Fort Lupton cemetery, Weld Co., CO, on 6 May 2006.

Incorrect species provided as answers:
none

Congratulations to the 28 of 28 getting the quiz correct:
Devich Farbotnik
Tyler Bell
Thomas Hall
Robert McNab
Su Snyder
Nick Komar
Jim Nelson
Margaret Smith
Christopher Hinkle
Pam Myers
Peter Wilkinson
Julie Rouse
Christian Nunes
Margie Joy
Ben Coulter
Michael Speegle
Barbara Deneen
Adrian Hinkle
Kirk Huffstater
George Cresswell
Tom Wilberding
Matt Bristol
Al Guarente
Marcel Such
Joe Bens
Joel Such
Bryan Guarente
Chishun Kwong

Answer: American Robin

Quiz #389 (2011-1-10) Solution

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Answer by Tony Leukering

Like last week's quiz, our choices quickly devolve to two options. This week, it's the black head and wings, rufous sides, and buffy undertail coverts that do that trick. Now, which is it, Spotted Towhee or Eastern Towhee? I've played with this duo a few times on the Mr. Bill Mystery Quiz, because they can be genuinely difficult and many birders do not fully understand all of the relevant field characters. And, of course, they hybridize in the central Great Plains.

What we can see of the wing coverts -- granted, not much -- reveals no spotting that would be typical of Spotted Towhee. However, recall that there is an unspotted (or mostly so) form of Spotted Towhee. But, I used that form fairly recently; would I do so again so soon? Hmm. Well, we can quickly rule out that little-spotted form of Spotted Towhee, as our quiz bird sports gigantic white tail spots taking up 3/4 of the length of the tail; that northwestern form of Spotted has considerably smaller tail spots. In fact, those extensive tail spots should rule out all Spotted Towhees except for the plains-breeding race, arcticus.

The important aspect of the view we get of this week's quiz bird is the primaries, and I provide an enlarged version of that part of the bird, below. Spotted Towhee has relatively little white in the primaries, with that color being restricted there to the leading edge of the outer primaries, but only the distal 1/5 to 3/4 of the length of individual primaries; that white does not extend to the primary coverts. Eastern Towhee shows at least one primary -- often, a few primaries -- on which the white leading edge extends the visible length of the primary and meeting the large patch of white at the base of the outer primaries adjacent to the primary coverts.



As can be seen on the enlarged inset, above, the white edges of many of the outer primaries extend to the white patch at the base of the primaries, which is indicated by the arrow. The important aspects of "Rufous-sided Towhee" ID is not presence vs. absence of white, they are the extent of white and where, precisely, the white is.

I took this picture of an immature male Eastern Towhee at Chico Basin Ranch, El Paso Co., CO, on 8 April 2006. Mark Peterson and I found this bird on 6 January 2006 while conducting the local Christmas Bird Count. This individual was the cause of the Long-billed Thrasher that wintered at this site being found, as Brandon Percival went there to check out our rare Eastern Towhee and found the thrasher! Below is a picture I took of the same individual on the day that Mark and I found it. In it, one can see that the primaries are noticeably browner than are the wing coverts, indicating its immaturity.



Incorrect species provided as answers:
Spotted Towhee - 7

Congratulations to the 18 of 25 getting the quiz correct:
Tyler Bell
Chuck Carlson
Ben Coulter
Nick Komar
Pam Myers
Christian Nunes
Ali Iyoob
Su Snyder
Gary Koehn
Robert McNab
Peter Wilkinson
Matt Bristol
Joe Bens
Joel Such
Marcel Such
Bryan Guarente
Devich Farbotnik
Thomas Hall

Answer: Eastern Towhee