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Because we don’t see shorebirds on any kind of a regular
basis here in land-locked Arizona, we become attuned every
fall (remember July/August is “fall” on the shorebird
calendar) to using our big scopes and meticulously detailed
field guides to focus on darting, wheeling flocks of tiny
peeps. Cursory
glances and uninformed expectations for our larger, easier to
identify long-legged waders may lead us to miss or misidentify
some beautiful, fascinating, and rare migrant shorebirds.
Let’s tune into them with this quiz.
A)—Good
photo, easy bird
Well, this is certainly no peep. This is a large shorebird with rather plain, unmarked plumage
but a visually spectacular structure.
The structural features that leap from the image are
the obviously long legs and the amazingly long, scimitar
shaped bill which appears jointed or notched at the tip.
Few of our North American bird species are as aptly named as
the Long-billed Curlew and, given a head profile such as we
have here, few are as readily recognizable.
Long-billed Curlew is our largest shorebird, some
females measuring over two feet in length, the bill itself
nearly a foot long. The
name “curlew” comes to us from the French imitation of
their haunting, two syllable flight call, and the genus name, Numenius,
comes from the Greek word for new moon, crescent shaped like
the curlew’s decurved bill.
There are, nonetheless, some identification caveats.
Curlews are often seen feeding in wet pastures or
flooded fields at distances great enough that bill length and
shape might not be readily discernible.
In these situations or in the case of a sleeping bird
with bill tucked under a wing or at rest against its back,
body size and plumage may suggest Whimbrel or Marbled Godwit.
Additionally, be aware that juvenile Long-billeds, seen
in the fall, can have much shorter bills than adults and
thereby in profile can easily resemble Whimbrels.
Behavioral traits dictated by structural differences can
offer interesting identification clues for distant birds.
Long-billed Curlews, as well as the godwits with their
upturned bills, feed more by probing whereas Whimbrels tend to
pick rather than probe. The
length of the bill and the flexibility of its seemingly
jointed tip allow Long-billed Curlews to angle deeply into the
soft sediment burrows of crustaceans and worms and open the
bill underground to capture these prey items.
Think of the tip of this marvelous bill as an inverted
spoon capable of tactiley locating food and scooping it toward
the tongue.
Long-billed Curlews are fairly common migrants through the
agricultural fields south and west of Phoenix in both spring
and fall, often in flocks of a dozen of more birds.
Pairs have been observed in Arizona grasslands during
breeding season, but nesting has not yet been documented.
This Long-billed Curlew was photographed at the Gila
Farms catfish ponds October 25, 1992.
B)--Good
photo, difficult bird
Here is another long legged wader with an outstanding bill,
this one slightly upturned and, like that of our curlew,
longer than the bird’s head.
Birds that might qualify on these two structural
criteria are American Avocet, Greater Yellowlegs, Willet, or
any of our godwits. Let’s
eliminate avocet because this bill is neither thin enough nor
upturned enough, and this plumage is mottled and cryptic
rather than bold lights and darks.
Eliminating the others on our list cannot be done quite
so readily.
The thick, slightly upturned bill of Greater Yellowlegs,
lighter at its base, looks to be a good match for our quiz
bird’s, and yellowlegs will show the dark loral line between
eye and bill that we see here.
But did we mention that yellowlegs have yellow legs?
Even in black and white, there is no shade of yellow
that would appear as dark as these legs.
Furthermore, our quiz bird’s plumage is also too
dark, particularly on the belly which in all ages of
yellowlegs is white or off-white.
Despite the boldly marked scapulars and dark flank
streaking which might define breeding plumaged Greater
Yellowlegs, these legs are not yellow and this is not a
yellowlegs.
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Willet presents another interesting possibility, assuming of
course you don’t see the beautiful black and white Willet
wing pattern of the bird in flight which would clinch the
identification. The
Willet bill is about half again the length of its head and it
is straight. “Long”
and “straight” are relative and at a distance can be hard
to judge. This
close-up profile, though, shows a bill twice the length of the
bird’s head, and the upturn is noticeable.
In breeding plumage, Willets’ scapulars are finely
spotted and barred and there is thin flank barring against a
white belly—not a description of our photo bird.
Long, thick, and upcurved does describe the bill of our four
North American godwits. Bar-tailed,
a coastal species, and Black-tailed, an Asian vagrant, have
not been recorded in Arizona and are not expected. Marbled Godwit is expected, both spring and fall, and is
listed as an “uncommon transient” in Birds Of Phoenix And
Maricopa County. It
is our largest godwit, nearly the size of a Long-billed
Curlew, and so similar in plumage that at a distance, without
the proper sight angle of the curlew’s sickle shaped bill,
the two species can and are often mistaken for one another.
Like Long-billed Curlews, Marbled Godwits appear mottled
brown above with fine white speckling and buffy below, with
cinnamon wing linings and an unstreaked head.
In breeding plumage Marbled Godwits show fine, dark
barring on the cinnamon belly, but juveniles passing through
in the fall have the same plain, unmarked underparts as
Long-billed Curlew. The
bill is bright, salmon pink with a dark tip.
What’s wrong with this picture? Well, it doesn’t fit the above description.
What we see in this picture is a godwit bill on a bird
that is boldly spotted above with conspicuously wide barring
on very dark underparts—a breeding adult, not a juvenile,
not a bird expected in the fall, not really a bird expected in
Arizona at all. This Hudsonian Godwit was photographed at the Willcox ponds
in May, 1996, at that time only the fourth state record, all
during spring migration.
C)—Bad
photo, easy bird
Many generally accepted principles of good photographic
technique take flight when the subject is birds, done in by
the unpredictability of that subject.
Composition is the most obvious of these and leads to a
paraphrasing of the standard aphorism of photographic
excellence--“f/8 and be there.”
With birds it becomes “f/8 and be lucky.”
You can learn to use your camera and you can learn to
find the birds, but you can’t learn lucky.
Look how pleasing the composition of the first two
images is compared to that of our third subject which
unluckily happened to be standing in front of a busy
background which partially obscured its bill shape and head
markings. And if
you move to change positions for a cleaner background, this
guy is on his way to Siberia.
Structurally this bird resembles our curlew though neither
the long decurved bill nor the long legs appear to be quite
curlew length. Most
noticeable, however, are two outstanding plumage differences.
The white mottling on this bird’s dark upperparts is
heavier and bolder than that of the curlew, and this bird has
a bold head pattern--thin white central crown stripe defined
by thick dark stripes over a light supercilium.
Whimbrel is our only large wader with these bold crown
stripes. It is
longer bodied than Long-billed Curlew and thus has a sleeker,
more streamlined jizz. In migration it is less common in Arizona than Marbled Godwit
and, though not unexpected, the flock of 213 noted in a field
near Yuma last April certainly expanded the limits of those
expectations. This
Whimbrel was photographed at the Sisson Road mudflats near
Painted Rock Dam after the floods along the Gila in July of
1993.
Though typically easier to identify, Arizona’s large
shorebirds are generally less common and also less
approachable than the little peeps we’ve come to love and
curse as we stand in the mud with our scopes and field guides.
Save some time this fall to seek out and savor these
long-legged beauties and their eye-catching structural
anomalies.
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