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BIRDING • JANUARY/FEBRUARY 2014
36
The identification challenge posed by fall and winter Chipping, Clay-colored,
and Brewer’s sparrows is a well-known problem that has been addressed sev-
eral times in the birding literature. General introductions and overviews are
provided by Kenn Kaufman (1990, rev. 2011) and Peter Pyle (1997), and addi-
tional details are provided in Birding magazine articles by David Simon (1977)
and Peter Pyle and Steve Howell (1996). This earlier literature summarizes nu-
Three long-tailed, pot-bellied, diminutive sparrows in the genus Spizella—the Chipping, Clay-col-
ored, and Brewer’s sparrows—are challenging to identify in their fall and winter (basic1and formative2)
plumages. Fortunately, the existing bird identification literature nicely describes differences among
these species in their fall–winter plumages—especially field marks on the birds’ faces as seen in pro-
file. But birders are always looking to push the envelope. In this article, bird ID enthusiast Nick Lethaby
presents a little-known and poorly described field mark that may actually be diagnostic for many
tricky birds in this Spizella trio. To see this mark, though, you have to look at the bird from behind!
And you need to appreciate the effects of plumage wear, age
differences, and geographic variation.
Over the years, the North American birding community has become well ac-
quainted with “the Spizella challenge.” The key is to get a good look at the bird’s
face in profile, as here (this is a Clay-colored Sparrow). For sure, that’s a great way
to identify these lookalike sparrows, even in fall and winter (note that this image is
from September). But has the conventional wisdom about Spizella ID forced us
into a particular way of seeing these lookalike sparrows? In this article, we take a
look at the sparrows from behind—and get a new perspective on an old ID chal-
lenge. Death Valley, California; September 2009. Photo by ©Bob Steele.
Hind-neck Pattern
An Additional Aid in Identifying
Spizella Sparrows in Fall and Winter
Nick Lethaby
Goleta, California
nlethaby@gmail.com
1This article follows the revised Humphrey–Parkes plumage terminology proposed by Steve Howell and col-
leagues, and presented by Howell to the ABA membership in the October 2003 and December 2003 issues of
Birding. See p. 52 for a discussion of the term “basic plumage.”
2A formative plumage is any plumage (almost always only one such plumage) present in a bird’s first plumage
cycle (approximately its first year of life) but lacking in all subsequent plumage cycles. For the purposes of this
article, the formative plumage of Spizella sparrows is the plumage that comes after the juvenile plumage; it is
molted in during the late summer or early fall, and held at least into late winter.
ABA.ORG/BIRDING 37
merous features useful in sepa-
rating these species—including
the presence of streaking on the
sides of the gray neck collar,
which separates non-juvenile
Brewer’s from other Spizella
sparrows.
While studying this feature, I
started to appreciate quite dis-
tinctive differences in the pat-
tern of streaking at the center of
the hind-neck—a region of the
bird not well displayed on birds
in profile, the way they’re so
often photographed and illus-
trated. In subsequent discus-
sions with other birders
regarding photographs of diffi-
cult birds, I learned that I was
not the only person to notice
these differences. However,
there appears to be no previ-
ously published, broadly acces-
sible material documenting
these differences. So it is my
goal here to digest what I and
others have noticed about the
differences among these three
sparrows in their formative and
basic (fall–winter) plumages.
Brewer’s Sparrow
The crown is uniformly
streaked, with some birds showing an ill-defined paler
median stripe . The collar in particular is covered by a
broad band of medium–long black streaks on gray-
brown ground color, as if the crown pattern extends to
the back. This pattern is exhibited even by Brewer’s
Sparrows that show unstreaked sides to the gray neck
collar. This individual, photographed by Peter Gaede on
September 29, 2013 at Santa Barbara Island, California,
is typical.
Clay-colored Sparrow
On this species, the crown is obviously divided by a
central pale line; two narrow lines of fine, short, black
streaking continue from the sides of the crown to cross
the gray collar. The black streaks may be set in a cold
brown wash. The gray collar is clearly visible between
Brewer’s Sparrow. Photo by © Peter Gaede.
Clay-colored Sparrow. Photo by © Jay Carroll.
these two lines of streaking. This individual, photographed
by Jay Carroll in November 2011 in San Luis Obispo, Cal-
ifornia, shows how distinctive this mark can be.
Chipping Sparrow
Not surprisingly, the geographically widespread Chipping
Sparrow shows variation in this trait. Many individuals,
like the one depicted here, show two solid dark lines ex-
tending down from the lateral crown-stripes (often starting
to show rusty by late fall) across the gray collar. These solid
dark lines typically show a rusty-brown wash to either side
that somewhat obscures the gray collar, which is darker in
tone than the collar of Clay-colored and Brewer’s. Other
individuals show a pattern much more similar to Clay-col-
ored, such that two narrow lines of fine black streaking set
in a rusty ground color extend across the gray collar. This
BIRDING • JANUARY/FEBRUARY 2014
38
I D E N T I F Y I N G S P I Z E L L A S P A R R O W S
Chipping Sparrow. Photo by © Nick Lethaby.
bird was photographed by the author on October 9, 2013
at Prisoner’s Harbor on Santa Cruz Island, California.
Variation: 1. Juveniles
In all three species, juveniles (seen from early summer
through mid-autumn, although this is geographically
variable) have extensively streaked under-parts, and all
can show streaking on the hind-neck. Birds in full juve-
nile plumage are extensively streaked over much of the
body and are obviously juveniles; on such birds, the
hind-neck differences described above are probably not
safe for separating species. Less obvious are individuals
that have retained some juvenile feathers but otherwise
have molted mainly into their formative plumage. If these
retained feathers include some on the hind-neck, then
such an individual would show a hind-neck pattern rem-
iniscent of a Brewer’s Sparrow. Although such an indi-
vidual would typically show other remnants of juvenile
plumage, such as streaking on the breast sides, the pos-
sibility of retained juvenile plumage should be consid-
ered in individuals that clearly show features associated
with a different species.
Variation: 2. Subspecies
As previously noted, Chipping Sparrows are geographi-
cally variable. Taxonomy is not fully agreed upon, but ge-
ographic variation in overall darkness of the bird is widely
acknowledged; this variation could affect the prominence
of hind-neck streaking in adult Chipping Sparrows in basic
plumage. The descriptions in this article of the Chipping
Sparrow’s hind-neck patterns are based on my field expe-
rience in California.
Perhaps less well known is the marked geographic vari-
ation in Brewer’s Sparrows. “Timberline” [Brewer’s] Spar-
rows (subspecies taverneri) are fairly distinctive in their
alternate (breeding) plumages, and Klicka et al. (1999)
have proposed full-species rank for the taxon. In a nut-
shell, alternate Timberlines are intermediate in many re-
spects between Clay-colored and nominate (breweri)
Brewer’s sparrows. Differences are muted in fall and win-
ter, however, with the result that migratory and wintering
ranges of Timberline Sparrows are poorly known. A chal-
lenge for enterprising birders will be to determine the vari-
ation, if any, in hind-neck pattern in formative and basic
Timberline vs. nominate Brewer’s sparrows.
Clay-colored Sparrows, unlike Brewer’s and Chipping
sparrows, are “monotypic,” having no named subspecies.
But beware of the possibility of overlap between Clay-col-
ors at the “soft” end of the spectrum vs. Timberlines at the
“sharp” end.
Variation: 3. ID Resources
I have found it challenging to detect nape patterns of mu-
seum specimens due to variation of preparation by dif-
ferent preparators, some making it difficult to examine
and interpret hind-neck plumage in detail. The great ma-
jority of photographs are of birds in profile—which to-
tally makes sense, given that the classic field marks are
best depicted from that angle. Unfortunately, such photos
can distort or obscure the hind-neck characters discussed
above.
It’s been said many times before, but it always bears re-
peating: Given the variation shown in many other features
by these species, it is not recommended that observers
treat the differences presented here as infallibly diagnostic.
I hope my observations stimulate conversation in the
broader birding community. I certainly welcome feedback
from observers on the frequency with which obvious in-
dividuals of a particular species show a nape pattern asso-
ciated with another species.
Acknowledgments
I thank Donna Dittmann, Ted Floyd, and Peter Pyle for
comments on an earlier draft of this article. Steve Cardiff
and Donna Dittmann at the Louisiana State University Mu-
seum of Natural Sciences and Moe Flannery at the Cali-
fornia Academy of Sciences granted access to collections of
Spizella specimens that were helpful in understanding
plumage differences and variation.
Literature Cited
Kaufman, K. 1990. A Field Guide to Advanced Birding. Houghton Mif-
flin, Boston.
Kaufman, K. 2011. Kaufman Field Guide to Advanced Birding.
Houghton Mifflin Harcourt, Boston.
Klicka, J., R. M. Zink, J. C. Barlow, W. B. McGillivray, and T. J. Doyle.
1999. Evidence supporting the recent origin and species status
of the Timberline Sparrow. Condor 101:577–588.
Pyle, P. 1997. Identification Guide to North American Birds, Part I.
Slate Creek Press, Bolinas.
Pyle, P. and S. N. G. Howell. 1996. Intraspecific variation and the
identification of Spizella sparrows. Birding 28:374–387.
Simon, D. 1977. Identification of Clay-colored, Brewer’s, and Chip-
ping sparrows in fall plumage. Birding 9:189–191.
ABA.ORG/BIRDING 39
Discuss this article and your own
observations and experiences
online: aba.org/birding