SPARROWS IN A
CHIHUAHUAN GRASSLAND
 Sparrows, so many sparrows this
morning, peeping and rustling in the leaves outside the tent. So as to not frighten them
away I furtively peep through a pinhole beneath the tent-flap's zipper. Outside I see a
carnival of mostly brown and gray, stubby-billed, chubby looking little sparrows, hopping
about, scratching in the soil, preening, stretching, and flitting from one grass stem or
sagebrush branch to another.
Mexico has about thirty-eight sparrow species and they all are variations on the themes of
smallness, being gray and brown, typically having striped backs, and having bills that are
short and conical, and thus well adapted for eating small grass seeds. Not a species among
them bears a single feather of blue, green, or red. Male and females look the same, but
juveniles have their own plumages, which are even less striking than the adults'. And around
me this morning, seventy to eighty percent are young birds in various stages of drab
juvenile plumage. They are this year's new crop. Identifying them will be a challenge and
a pleasure.
I'm able to name two or three species immediately because of the presence of a few adult
birds with distinctive fieldmarks. However, to positively identify six sparrow species it
takes two days of patient watching, of reading and rereading species descriptions in my
field guide, of studying habitat preferences and species ranges, and of vainly hoping that
an adult male will break into its distinctive song.
For two days I drift through the tall grass and among the low, spiny mesquites and
acacias, meditating on the meanings of lesser or greater degrees of brown striping on
backs, lesser and greater degrees of spotting on chests, mere hints of eye rings or eye
stripes, mere hints of median crown stripes, and occasional, half-hearted, fractionally
articulated songs. And these two days are a joy.
You need special powers of observation to identify birds well. I look at one of these
sparrows, make all the mental notes I can on breast spotting and back streaking, on
whether it has an eye stripe or an eye line, or maybe a line through its crown. Once I
think I've noted everything, I put down the binoculars and look in the field guide, and
then I realize I hadn't seen nearly enough.
Had the bird's tail been forked, squared, or rounded? Had its lower mandible been the same
color as the the top one, and had its legs been dark or pale? Nearly always by the time I
realize that I must look at the bird again, already the sparrow has flown away. I feel as
if all these sparrows orbiting around me in their flitting, ephemeral, seemingly
unconcerned manner comprise a kind of diffuse Zen master who half teasingly, half
tauntingly draws me into a frame of mind where, to glimpse the essential beauty of the
thing, ever greater self-discipline is needed, ever clearer vision.
In the end, knowing that I've probably overlooked two or three species, here, in
alphabetical order, are the six sparrows I identify with absolute certainty:
- Black-throated Sparrow
- Clay-colored Sparrow
- Rufous-crowned Sparrow
- Song Sparrow
- Vesper Sparrow
- White-crowned Sparrow
Now let me tell you about each of these:
BLACK-THROATED SPARROW -- photos and
more info
Adults wear conspicuous black bibs below their bills, and bold,
white eyebrow lines over their eyes. The species limits itself to desert scrub and has a
special fondness for creosote bush. The bird's range is smaller than a lot of sparrows',
only nesting as far north as southeastern Colorado, and wintering as far south as central
Mexico It's absent throughout the East. The bird flies erratically and close to the
ground, nervously flicking its tail, almost as if it were jittery about something. This a
restrained, neat-looking, nervous little bird.
CLAY-COLORED SPARROW
-- photos
and more info
Particularly small, this bird has no striking feature of plumage
other than a modest, pale stripe across a dark-brown head-crown. More a generalist than
the scrub-loving Black-throated Sparrow, it inhabits a hodgepodge of habitats -- scrub,
second-growth, edges of both deciduous and coniferous forests, burns, along rivers... Its
song, which isn't being sung now, is nothing musical, rather just three to four identical,
slow, low-pitched, flat, unbirdlike buzzes. Studies have shown that the pure, clear
whistles of forest birds become severely distorted by strong temperature gradients and air
turbulence. The Clay-colored Sparrow's low-pitched buzzes, then, is adapted for windy,
open places just like this. Most North American birds are found in either the East or the
West, or from coast to coast, but Clay-colored Sparrows only occupy the center of the
continent. You can see its summer breeding distribution here.
The species winters from southern Texas to southern Mexico.
RUFOUS-CROWNED SPARROW
-- photos
and more info
This is by far the most abundant species here, with more juveniles
in more intermediate stages of confusing plumage than any other. It forages on the ground
seldom moving high in vegetation. Often it scurries from one bush to another instead of
flying. Sometimes it sings a few snippets of song, even though nesting time is far away.
The song is a little musical, with many rapid notes, but the notes are weak and jumbled
with no discernable structure. One feature setting it apart from the other five sparrow
species is that it's the only one that doesn't migrate. I take this to mean that of all
the birds here, this is the one most at home.
SONG SPARROW -- photos and
more info
This bird is "family" for me. Distributed from southern
Alaska to Newfoundland, south at least to southern Mexico, it was with me in my old
Kentucky home. Though several generations of bird were probably involved, my mother
considered the Song Sparrow claiming our backyard as the same individual year after year,
and she called him Chesty. "Chesty," because when he sang he threw back his head
and puffed out his boldly striped chest. My mother would always say, "Just listen to
Chesty out there singing his little heart out."
VESPER SPARROW -- photos and
more info
The books always speak of the Vesper Sparrow's sweet song. I've
never been up North during the species' nesting season so I don't know how sweet the song
is. To see if you agree with The Audubon Society Master Guide to Birding's
description of the song as ". sweet, musical opening notes, usually 2 pairs of clear,
unhurried, slurred notes, second pair higher pitched, followed by a descending series of
rapid trills," you can hear the song here. Not having its
song to help with identification, I'm glad that Vesper Sparrows have an easy-to-see
fieldmark. Their shallowly notched tails have white outer feathers that flash when the
bird flies. A few other sparrow tails have white outer feathers, but those tails are
rounded, not notched.
WHITE-CROWNED SPARROW
-- photos
and more info
 This bird also has a
vast range, nesting as far north as northern Alaska and northern Quebec, and wintering as
far south as central Mexico. Though as a child in Kentucky I knew this bird, it was fairly
uncommon and appeared there only during the winter. In the picture, notice the bold,
black-and-white head striping. In Volume 146 (1964) of Science magazine,
L.R. Mewaldt reported on an experiment for which he'd captured White-crowned Sparrows in
San Jose, California, marked them and flown them by aircraft to Baton Rouge, Louisiana,
and Laurel, Maryland, where the birds were released. The following summer they presumably
migrated to their nesting grounds, most likely in Alaska, and then the following winter
they showed up once more in San Jose, California... If you know how hard it is to get a
fix on one's longitude (east-west position), you'll understand how surprising this is.
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