ABA Online Bird Photo Quiz 4

Answer

Bird Photo

Structure is perhaps the most important single clue to a bird's identity. In general, when we try to identify a bird, we focus on its head to narrow down the list of what it might possibly be. A bird's bill is particularly useful in placing a bird to the proper family-in most cases we are unlikely to confuse a thin-billed warbler with a thick-billed finch. Of course, there are times when we just can't see a bird's bill, and in these cases we must focus on other clues.

Even without the bill (or much of the head), we can see a lot about this bird, and it's probably a good idea to study the bird and figure out what we can see before we start naming birds that look similar.

It's obvious that this month's quiz bird is a perching bird, or passerine. On this passerine the crown appears to be an olive-yellow color that extends onto the mantle and contrasts in color with the blue-gray rump and uppertail coverts. The tertials have broad white edging, and we can easily make out broad white tips to the greater coverts (forming a conspicuous lower wingbar). We can't see the median coverts. The legs are blue-gray and relatively stocky (but not particularly short). The bird seems relatively chunky and has a noticeably short tail.

Some species, like the Verdin, may look rather similar to our bird if we look at the general coloration (yellow head and grayish body). But many of the little details aren't right for that species. Our bird has contrasting tertial edges and at least one broad white wingbar. A Verdin is mostly grayish without contrasting broad tertial edges or wingbars.

There are a handful of warblers that are similarly colored. The yellow-green coloration may remind some observers of a Chestnut-sided Warbler, but on that species the yellow-green coloration extends all the way down onto the rump. The tertial edges and greater coverts are also more olive colored (not white) in basic-plumaged Chestnut-sided Warblers, and we should see at least some fine black streaking on the upperparts of a Chestnut-sided Warbler. Bright male Pine Warblers can look similar to our bird, but Pine Warblers have more uniformly colored upperparts with an olive colored rump and uppertail coverts-not the contrastingly blue-gray rump and uppertail coverts present on our bird. Furthermore, the yellow on the underparts does not extend as far onto the flanks on our bird as it would on a Pine Warbler.

An Olive Warbler, which now isn't thought to be a warbler at all, is rather similarly colored. Still, the details aren't right. The Olive Warbler would not have as broad white tertial edges as our bird, and the olive-yellow coloration on the head also extends too far onto the mantle for that species.

Female Pine Grosbeak bears a strong similarity to our bird, but there are a few problems. Typically, Pine Grosbeaks have at least some yellow (or olive or russet) coloration on the uppertail coverts, particularly on a bird where the yellow coloration on the head extends this far onto the mantle. The proportions of our bird are also not right for a Pine Grosbeak. The tail is too short for the relatively long-tailed Pine Grosbeak. Furthermore, the legs are too stout and appear too long for a Pine Grosbeak.

The combination of an olive-yellow crown with the olive yellow extending down onto the mantle, the blue-gray rump and uppertail coverts, the broad white tertial fringes and white tips to the greater coverts forming a lower wingbar, and the relatively stocky shape, short tail, and thick blue-gray legs indicates that we are looking at a Yellow-throated Vireo. 

This Yellow-throated Vireo was photographed by the author in June 2003 in Aitkin County, Minnesota.

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

  1. Bertram E.B. Bree, Jersey Island, Channel Isles
  2. Brian.O. Bree, Jersey Island, Channel Isles
  3. Thomas Schultz, Green Lake, WI
  4. Gary Edwards, Seneca, PA
  5. Melissa Hein, North Branch, MN
  6. George E. Wallace, Warrenton, VA
  7. Dave Magpiong, Bellmawr, NJ
  8. Jared Mizanin, North Royalton, OH
  9. Mike Ramsden, Beloit, WI
  10. Larry Semo, Westminster, CO
  11. Dave Tietjen, Huntsville, AL
  12. Danny Jacobs, OH
  13. Chris Litherland, Kingwood, TX
  14. Knut Eisermann, Guatemala Ciudad, Guatemala
  15. Claudia Avendano, Guatemala Ciudad, Guatemala
  16. Oliver Komar, Lawrence, KS
  17. Sam Stuart, Mont Clare, PA

How Did You Compare?

The graph below shows that the highest number of answers submitted was for Pine Grosbeak (32), followed by Yellow-throated Vireo (17). We received a number of answers that did not conform to the ABA Checklist format. Please note that answers must consist simply of the Common or English name exactly as it appears in the ABA Checklist.

Bird Graph

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The photo and answer for this quiz were supplied by Chris Wood.