nature's garbagemen

7/29/2019 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



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

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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



~.~ ----._

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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nature's garbagemen

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