ABA Online Bird Photo Quiz 5

Answer

Bird Photo

A completely unobstructed view of a bird on a post is always a treat for a birder and perhaps even more welcome with challenging "quiz birds". When you're confronted with an unknown bird, it's important to start with shape, so that you can quickly narrow down the list of possibilities. Even with only one image, you can get an excellent feel for the shape of this bird. Our bird is slim, with a relatively long tail, a rather long, slightly decurved bill, and legs that appear rather stout and strong. The overall proportions suggest that this is a medium-size bird, something along the lines of a thrush, oriole, or thrasher.

In general, thrushes are not as slim as our bird, nor would any but a disfigured bird show a bill with this shape; the tail is also too long for any thrush. Despite the rather oriole-like shape, it is easy to see that no oriole would be as overall gray-brown as our bird. Rusty and Brewer's Blackbirds and even Common Grackle come a bit closer to our bird in terms of plumage, and all can have a rather uniformly colored mantle like our bird. Yet none of these species are quite right in terms of shape, and the pale sides of the neck with brown streaks aren't right for any of these birds.

We are left with the mimids (mockingbirds, thrashers, and catbirds), which usually have a rather long tail, a decurved bill, and strong legs, which they use for running. This is a small family, but one that is full of identification challenges. Our bird is mostly gray-brown, without the gray color to the wings and tail. We can quickly eliminate Brown and Long-billed Thrashers. For a thrasher or mockingbird, the bill on our bird is on the short side, not nearly as long or strongly decurved as on California, Crissal, or Le Conte's Thrashers. The overall brownish plumage makes it mighty tempting to jump quickly to Bendire's Thrasher, or perhaps a young Curve-billed Thrasher that could have a similarly shaped bill.

But let's put the brakes on for a moment and think of one other important clue: the date. The date is an extremely important clue in the case of an unknown bird. Luckily, this is something you always know in the field.1 This photograph was taken in early July, when thrashers are either in very fresh plumage (juveniles) or very worn plumage (adults). Our bird is certainly worn, so much so that it is rather difficult to see where one tertial ends and another begins, and it is impossible to see individual feathers on the mantle.

Looking a bit more closely now, we see some things that are inconsistent with Bendire's or Curve-billed Thrasher. Most notably, the sides of the neck are rather pale and distinctly streaked. Looking carefully at the underparts, we note that the flanks as far up as we can see are sharply streaked. The streaks on the sides of the neck and flanks are also inconsistent with Northern Mockingbird.

Only two mimids in the ABA exhibit this combination of characters: the Sage Thrasher and the Bahama Mockingbird-two species that one rarely confuses while birding. Careful examination reveals that our bird's wings look too brown for even an extremely worn Bahama Mockingbird. The color of the feet is worth paying attention to: they are not blackish as on the Bahama Mockingbird, but rather paler gray as with the Sage Thrasher. Furthermore, the pale sides of the neck that almost form a collar are very pale for the Bahama Mockingbird. The combination of all these characters is enough to eliminate the Bahama Mockingbird.

Mark Peterson photographed this Sage Thrasher in Colorado on 6 July 2003.

1. Even on extended vacations when we lose track of whether it's Wednesday or Sunday, we still generally know whether it's June of August. Since the purpose of these quizzes is educational and to present birders with situations that are similar to what they may experience while actually birding, we will always try to give you an idea of the general time of year (e.g., early August or late December).

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The following people (listed by submission date beginning with the earliest) submitted correct answers for the August Bird Photo Quiz—Sage Thrasher:

  1. Oliver Komar, Lawrence, KS
  2. Mitch Ratzlaff, Newberg, OR
  3. Nathan Hentze, Cumberland, BC
  4. Knut Eisermann, Guatemala Ciudad, Guatemala
  5. Michelle Scott, Santa Cruz, CA
  6. Kalen Malueg, Hooper, CO
  7. Bill Maynard, Colorado Springs, CO
  8. Beth Rewald, Dousman, WI
  9. Bertram.E.B.Bree, Jersey Island, Channel Isles
  10. Brian.O.Bree, Jersey Island, Channel Isles
  11. Larry Kline, Woodbidge, VA
  12. Bob Miller, Calipatria, CA
  13. Tom Hedwall, Flagstaff, AZ
  14. Claudia Avendano, Guatemala Ciudad, Guatemala
  15. George E. Wallace, Warrenton, VA
  16. Nadine Atalla, Lee, MA

How Did You Compare?

The graph below shows that the highest number of answers submitted was for Bendire's Thrasher (31), followed by Sage Thrasher (16). 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.