ABA Photo Quiz

ABA Online Bird Photo Quiz 172

Answer

Another faceless quiz bird; what are we to do? While faces generally provide a lot of ID-important clues, they are not the end-all, be-all of bird identification. As I have stressed many times in this and other venues, the larger one’s identification toolbox, the more likely the arrival at the correct ID.

Tail spots are a very useful tool that ought to be in every birder’s toolbox and are often critical in identification of poorly seen warblers. In many situations, they cannot provide the identification by themselves, but in conjunction with one or two other features noted on a leaf-hidden warbler, they can help nail an ID as readily as a good look at the face. For some species, tail spots can be definitive by themselves. Crack open either of the warblers guides (Warblers or The Warbler Guide) and see for yourself.

Tail spots are contrastingly pale – nearly always white – areas on the inner web of individual tail feathers (hereafter rectrices; singular “rectrix”). As such and because of the way the tail folds (central rectrices on top, with each successive right-and-left pair of rectrices layered under the previous), they can be seen on the closed tail only from below (as in our quiz photo). From above, they can be seen on the spread tail, but even then, the pattern created is different from that as seen from below (Sibley provides topside spread-tail and underside closed-tail views for every warbler species because this feature is so important).

So, what are the possibilities for our tail-spotted warbler? First, we can immediately rule out all the non-tail-spotted warblers, which are nearly all warblers not in the genus Setophaga (formerly Dendroica). Second, we can also immediately rule out American Redstart and Yellow Warbler as both lack white tail spots. Third, we might study the shape of the white on the quiz bird’s tail, comparing it to the dark parts of the tail. We can see that the blackish edge to the tail is wider at both the base and the tip of the tail, creating a rough oval of white. Just that feature helps rule out a large number of warbler species, specifically those species in which the outermost rectrix has the inner web entirely (or virtually so) white and those on which the blackish edge is wider only at the tip or only at the base, not both. Excluded by this feature alone are Black-and-white; Prothonotary, Golden-winged, and Blue-winged; Hooded; Blackburnian; all members of the Black-throated Green group of species; Chestnut-sided; Pine and Prairie; Grace’s; and Fan-tailed warblers and the two Myioborus redstarts. We can also rule out the species with distinctive tail-spot patterns:  Kirtland’s, Magnolia, and Palm – the first has a wide black base to the visible tail, separating the tail spots from the undertail coverts, while the other two have the tail essentially half white split horizontally, with the base white in Magnolia, the tip white in Palm. We can also rule out the non-warbler Olive Warbler on this feature.

With just a gross tail-spot pattern to go on, we have ruled out 44 species of ABA-Area warblers, plus the other no-longer-a-warbler species known as Yellow-breasted Chat. Looking a bit more closely, we might notice that the tail is fairly long, so we can rule out the quite-short-tailed species with tail spots:  Cerulean, the two parulas. By my estimation, this now leaves us with just six species remaining in the possible solution set: Cape May, Bay-breasted, Blackpoll, Black-throated Blue, Yellow-rumped, and Yellow-throated. And we’ve looked only at the tail!

Looking higher up the bird, the wing bars are far too unimpressive to be those of Bay-breasted Warbler (which has the broadest wing bars of any ABA-Area warbler), and are also too weak for our bird to be a Blackpoll or Yellow-throated. Conversely, the wing bars are too strong for Black-throated Blue (which, of course, lacks wing bars). This leaves us with a dichotomy that trips up many a fall birder. If we could see the throat and whether it has streaking or not, we would have a solution. We can, however, see some of the bird’s upper tail coverts, which will do the trick quite nicely. Just above the fluffy whitish under tail coverts that are spread and covering the top of the base of the tail, we can see two black feathers, with the more-proximal one being edged in gray. Cape May has greenish upper tail coverts.

In summation, our ID was effected by observing two aspects of the tail, the wing bars, and the upper tail coverts. As I noted above, tail pattern and one or two other features can identify nearly every ABA-Area warbler species, and that without seeing the head!  Other features that we might have used, but did not need, include the black mandible, the brown head and back, the blackish legs, the longish primary projection, and the tertial pattern.

I took this picture of an adult (aged by the pattern on the upper tail coverts) Yellow-rumped Warbler in Cut Bank, Glacier County, Montana, on 6 October 2015.  Another picture of this individual is presented below.

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The following people (listed by submission date beginning with the earliest) submitted correct answers for the July 2017 Bird Photo Quiz —Yellow-rumped Warbler:

  1. Elliot Schunke - Tallahassee, FL
  2. Ryan Zucker - New York, NY
  3. Tim Swain - Concord, Massachusetts
  4. Collin Stempien - Mobile, Alabama
  5. Daphne Asbell - Tallahassee, Florida
  6. Chris Swarth - Mariposa, California
  7. Clifford Hawley - Sacramento, CA
  8. Mike McDowell - Middleton, WI
  9. Frank Fogarty - Davis, California
  10. Shane Brown - Granville, OH
  11. Isaac - Kamloops, BC
  12. Walker Catlett - Charlottesville, VA
  13. Bridget Spencer - Vancouver, BC
  14. Philip Kline - Portland, OR
  15. Julie Desmeules - Quebec City, QC
  16. Adonis Belize - Bowie, MD
  17. Kim Silver - Silver Spring, MD
  18. Celestyn Brozek - Albuquerque, NM
  19. Andy Eckerson - Dighton, MA
  20. David Rankin - Moreno Valley
  21. Nick Mrvelj - Portland, OR
  22. Kyle Lima - Ellsworth, ME
  23. Jared Parks - Church Hill
  24. Aaron Polichar - San Diego, CA
  25. Stephen Joly - Kamloops, BC
  26. Cole G. - Vancouver, BC
  27. Ian Ruppenthal - Davidson
  28. Richard Cissel - Carney, MD
  29. Kaylin Ingalls - Kirkland, WA
  30. Jeff Graham - Okinawa, Japan
  31. Cathy Sheeter - Oradell, NJ
  32. Ed Harper - Carmichael, CA
  33. Aiden Moser - Henniker, NH
  34. Robert Packard - Riverside, CA


How Did You Compare?

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.



Northern Mockingbird
16
Gray Kingbird
5
Ash-Throated Flycatcher
2
American Pipit
1
Alder Flycatcher
1
Black-throated Gray Warbler
1
Cape May Warbler
1
Chestnut-collared Longspur
1
Clark's Nutcracker
1
Dusky Flycatcher
1
Dusky-capped flycatcher
1
Eastern wood-pewee
1
Greater Pewee
1
Grey Jay
1
La Sagra's flycatcher
1
Pine Warbler
2
Willow Flycatcher
1
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 

 

 
 
 
 
 
 
 
 
 
 

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The photo and answer for this quiz were supplied by Tony Leukering.