nature's garbagemen
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Turkey vultures, awkward and ugly on theperch, spend much of their time cruising low in the sky, using their keen
sense of smell to detect the scent of their [avorite food: theflesh of recently killed animals.
their two eggs inahollow log, acaveor adip inthe
earth.
ark Catesby, an 18th-century naturalist,
artist and author of the poetically composed Natural
History of Carol ina, F lor ida and the Bahama Islands,
drawsmost of his birds aswhimsically perched among
abunch of flowers or on abranch, but his image of a
"TurkeyBuzzard" is stark, grey and flat with ablank
staring eye, long slimclawsand an embarrassingly
pathetic pink head. Uncharming asthe drawing is,
however, it depicts perfectly one of the characteristics
of all NewWorld vultures: anasal hole that passesstraight through the beak. "Think of acarcass and all
the blood," saysBarnhill. "They can just shake theirheads and clear it out." In turkey vultures, this nostril
is especially pronounced, and, indeed, they use it to
pick up the odor of decay on thewind. Their excellent
sense of smell, absent inmost birds, wasproved in a
1980sstudy in which turkey vultures repeatedly located
day-old chicken carcasses hidden under the canopy of
aPanamanian rainforest. Black vultures, poor smellers,
will watch turkey vultures, and when they see one swoop
intently downward, agroup ofmore-aggressive black
vultures will sometimes run the turkey vulture off thecarcass.
Helpful as they are, vultures can be pests. Noel Myers,
South Carolina director of wildlife services for the U.S.
Department of Agriculture, saysthat his officegets a
couple of calls aweek, mostly about themore aggressive
black vultures. They have been known to shred boat
covers and boat seats, children's swimming pools,tractor seats, even rooftop shingles. Their regurgitation
and droppings areunpleasant, ifnot dangerous, andvery, very rarely they will kill anewborn lamb or calf.
Vultures areprotected under the Migratory Bird Treaty
Act, but Myers suggests to his callers, "Start harassing
them-make loud noises, use firecrackers, if there's a
dead tree they are roosting in, maybe take care of that.
Make sure there's no food source-pet food, garbage
cans, roadkill."
In our fascination with the natural world, the ugly
vulture often gets abad rap or altogether overlooked."They're not acolorful songbird," saysBarnhill. "Most
people don't really think about them." The common
name "buzzard" has,come to imply something on
wings that is common, plain, dirty and ignorable. But
the Latin names of the black and turkey vultures give
them their due. Coragyps atratus translates to the
delightfully mysterious "raven-vulture clothed in black,"
and the turkey vulture (cathartes aura) isnamed for
itsmost ideal and astonishing quality-an homageto "catharsis," the vulture's job of purging, renewal,
cleansing and purification. ~
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Emily D. J ohnson recently completed her MFA in
nonfiction writing at the University of Minnesota. Her
thesis focused on both mathematics and faith.
May-June 2008 27

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silent. And lucky for us, themacabre tools that allow
vultures to consume the dead alsomake them nature's
garbagemen: As they take advantage of an unappetizing
but never-ending food source, they do us afavor by
clearing out a lot of really nasty stuff.
n fact, vultures are so helpful that nature
invented them twice. Recent DNA evidence hasconfirmed that "New World" vultures-the seven
species in North America and South America, including
the California and Andean condors-are actually
part of the stork and ibis family and resemble theraptor-related "Old World" vultures of Europe, Asia
andAfrica through aperfect example of convergent
evolution.
Though genetically distant, Old World vultures serve
an almost identical function to those in theNew World,
and arecent crisis on the Indian subcontinent showsus
what could happen if our vultures went missing. In the
last fewyears an animal medication called Diclofenachas devastated the Indian vulture population, and
asferal dogs and rats have stepped in to mop up the
mess left bythe absent vultures, they could spread
disease, especially rabies, to the human population. The
vulture crisis has had cultural effects, too: an Indian
Zoroastrian Parsi community that traditionally uses
vultures in ceremonies called "skyburials" has had to
find alternate ways to dispose of their dead.
Right now our black and turkey vultures are doing
just fine, however, according to Laurel Barnhill, bird
conservation coordinator for the S.C. Department of
Natural Resources. South Carolina's population is
increasing at about 2percent ayear, and nationally,turkey vultures expanded their range northward during
the first half of the 1900s,pushing their lirnits fromNew
Jersey into southern Canada, possibly by following the
newly built interstate highway systemand itsproductionof roadkill.
Of the twoSouth Carolina species, the turkey vulture
is themore idealized vulture, with itstiny, wrinkled
red head. Itswheeling flight is also quintessential:
What galumphing awkwardness it has on the ground
evaporates in flight. Waiting to take off until late
morning when buoyant columns ofwarm air begin to
rise, the turkey vulture will glide for hours with its six-
foot wingspan held in an elegant and unchanging "Y,"
thickly edged with silvery feathers, graceful as any eagle.
The black vulture's flight isalittle lessmagnificent;
it is identifiable by itsshorter tail and smaller, white-tipped wings that flapwith much greater frequency.
Otherwise, the birds share alot of similarities. Both
are large birds-turkey vultures weigh about 6pounds
and black vultures weigh a little less. Both roost in largegroups, but black vultures tend to bemore social and
more aggressive. Both species prefer fresher rather than
more decayed meat, and both nest on the ground, laying
1
Although black vultures don't measure up to turkey vultures in thesizedepartment, their aggressivenature and tendency to
travel ingroups enable them totake carcassesfrom themoresolitary turkey vultures that often arrivefirst) thanks totheir
superior sense of smell.
26 South Carolina Wildlife

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~.~ ----._
eall know vultures eat dead
things. ith their ironclad stomachs,
they can ingest roadkill, rancid meat,
farm animals dead of unknown causes,
bacteria, viruses, rabies, botulism, hog
cholera and possibly anthrax. They
process these things sowell with the acid and digestive
enzymes of their guts that their excrement is akindof salve that canbe dumped down their own legsfor
protection as they wade knee-deep in the open entrails
of day-old carcasses.
Because vultures can do this, because they havebald
heads to avoid becoming bloody and matted from
rooting around in adead animal, and because theirbeaks aremade to twist and detach flesh, they have
acquired areputation: dark, hulking shapes in the trees,
sinister and cartoonish likesome kind of Nast political
drawing, thewheeling and screeching harbingers ofdeath.
Is this reputation deserved? In South Carolina wehave
two kinds of vulture, black and turkey, and they're both
pretty harmless. They have talons, but their feet are too
weak to grasp amouse; their only means of defense is
to vomit, and they only do that when threatened. The
high-pitched screeching noise youmight associate with
the birds ominously circling aHarrison Ford-type as
he clawshisway across adesert isreally the call of a
red-tailed hawk; apart from ahiss or grunt, vultures are
A group of turkey and black vulturesperched on agnarled limb
castsan eeriepall, even onaclear blue-sky day. Caricatures of
turkey (left inset) and black vultures (right inset) wheeling about
in thesky above acarcass, spine-tingling as theyare, belie the
importance of their rolein thefood chain.
iv!ajc!une2008 25
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