What
signs of spring have you spotted lately? About a month ago, my dad reported
seeing his first turkey vulture of the year down in Iowa. Most people probably don’t
associate these drab, brownish-black scavengers with spring--or even realize
that vultures may have flown as far as South America for the winter--but they
are one of the earliest returning migrants. “What blazes the trail,” writes
Mary Oliver, “is not necessarily pretty.”
Sure
enough, a few weeks after Dad’s report, I caught sight of the V-shaped wings
and rocking, unsteady flight of a turkey vulture soaring above my road. I
suppose the “buzzard” had to wait until temperatures increased enough for
warm-air thermals to rise and buoy up its gray-fingered wings.
For as
long as I can remember, Dad has been pointing out every turkey vulture (TVs he
called them) soaring over every road trip we ever took. And it was fun, even as
a kid, to be able to easily identify such a large bird flying so high up in the
sky. They have an excellent gross-factor, too, which kids love. “Don’t get to
close to a turkey vulture,” warned the park ranger on my first grade field trip
to Effigy Mounds National Monument, “they’ll throw up all over you!” That I
still clearly remember this fact, and the moment I learned it, is an excellent
argument for outdoor education.
Since
that day, I’ve discovered many more gross facts about turkey vultures. First of
all, projectile vomiting is a defense they use against predators, not just
curious humans. The foul-smelling mix of semi-digested meat and digestive
fluids can sting if it reaches the predator’s eyes. In addition, emptying their
stomach may be necessary to lighten the load for take-off and escape if a TV is
interrupted while gorging on a roadside carcass.
Turkey
vultures don’t just spray gross stuff on enemies; they also defecate on their
own legs. This habit has a scientific name (urohidrosis) and a valid purpose.
As water evaporates from the combination of urine and feces (birds don’t
separate their waste like we do) it cools the blood vessels in their legs and
feet. It’s quite handy, actually, if you can’t sweat.
Even
without sweating, vultures’ feathers sometimes become damp during dewy, foggy,
or rainy nights. Then, while they wait for the air to warm enough to begin
rising in thermals, TVs perch in a spread-winged stance in the sunshine. This
not only dries feathers, but it warms their body, and bakes off bacteria.
Not
everyone sees vultures as gross. Tibetan Buddhists practice “sky burials,” where
vultures consume the dead, and Buddhists respect the birds for their role in
cleansing the earth and continuing the food chain.
While
their diet of rotting meat may repulse us, turkey vultures dispose of carcasses
that could otherwise breed disease. Can you imagine a world in which dead
things all rotted slowly in place? Turkey vultures embody the fact that “the
secret name of every death is life again.” (Mary
Oliver, Skunk Cabbage)
In
response to their diet, TVs have developed excellent immune systems that can
ward off and even destroy the microbes that cause botulism, anthrax, cholera, and
salmonella. Their stomachs, gross as they may seem, help purify our world.
Indeed,
despite their gross appearance, every adaptation of the turkey vulture seems
aimed at cleanliness and purification. Even their bare, ugly heads serve to
keep turkey vultures clean. While they are feeding on those carcasses, TVs
sometimes need to stick their heads deep into the cavities of the dead animals.
They preen the rest of their body feathers frequently, but can’t clean their
own head. The lack of feathers allows sunlight to sterilize their skin.
While
we don’t usually think of urine as cleansing, turkey vulture urine helps to
kill bacteria they might have acquired while walking over a dead animal.
So
although they may appear gross, TVs’ scientific name -- Cathartes aura—is quite appropriate. It means “purifying breeze.”
And in
fact, the story of the vultures – of winter’s rotting wounds transformed and
purified, of the purifier rising up into the sky, of it returning to cleanse
the world again and again—sounds a lot like another story I often hear this
time of year.
“Like
large dark lazy butterflies they sweep over the glades looking for death, to
eat it, to make it vanish, to make of it the miracle: resurrection...” from Vultures by Mary Oliver.
For over 45 years, the Cable Natural
History Museum has served to connect you to the Northwoods. Come visit us in
Cable, WI, at 13470 County Highway M. The current exhibit, “Deer Camp: A
Natural and Cultural History of White-tailed Deer,” opened in May 2013 and will
remain open until April 2014.
Find us on the web at
www.cablemuseum.org to learn more about our exhibits and programs. Discover us
on Facebook, or at our blogspot,
http://cablemuseumnaturalconnections.blogspot.com
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