An Excerpt from Jim Conrad's
Naturalist Newsletter of August 28, 2005
issued from California's Sierra Nevada
OVER THE CANYON
Most any moment of most any day I can look out over the canyon next to the house and
see one or more Turkey Vultures circling about. Consequently at least once a day this
question crosses my mind: How on Earth can there be enough carrion out there to keep so
many vultures alive?
On my hikes I seldom encounter dead animals, and most of the ones I do find lie along
roads. Often when I pass down those roads a day or two later the roadkill is still there,
so the mystery only increases.
This week my curiosity finally reached the Googling stage, and I think I may have part
of the answer.
For one thing, vultures eat a lot of small dead animals you'd not expect them to find
many of -- shrews, voles and moles, for instance. Then they also eat insects and other
invertebrates, and not necessarily just dead ones. In fact, vultures have been seen eating
living specimens of everything from newly born pigs to baby herons and ibises. Finally,
vultures do eat a fair amount of plant material. There's at least one report of 62
vultures attacking some frost-softened pumpkins.
While looking for the above information I ran into some other interesting facts about
vultures. For example:
- Discounting the nearly extinct
California Condor, in North America we have two vulture species, the Turkey Vulture found
nearly throughout the US, and the Black Vulture of the southern states. In the Yucatan, by
the way, we have four vulture species, one being the King Vulture, which is mostly white,
with a yellow, red, orange and gray head!
- A group of vultures is called a
"venue," while several vultures circling in the air constitute a
- American Vultures have good senses
of smell, but African vultures don't. The Turkey Vulture has the best sense of smell of
all American vultures.
- American vultures are closely
related to storks, while Old World vultures are closely related to hawks and eagles. This
is a classic case of convergent evolution -- unrelated species evolving toward the
"optimal form" for a given ecological niche, and therefore looking more and more
alike as evolution progresses.
- Vulture poop is actually a
sanitizer! It contains so much uric acid that it kills bacteria.
- Vultures pee on their own legs,
which helps them cool off, as well as sanitize their legs after their last meal.
- American vultures find food both
with their eyesight and sense of smell.
- Vultures prefer to eat fairly fresh
flesh. They will pass up putrid flesh if an alternative is available. They also prefer the
flesh of herbivorous animals, not carnivorous.
- The oldest known Turkey Vulture is
33 years old and lives in the San Francisco Zoo.
- The stinky odor that attracts Turkey
Vultures is called mercaptan. It's a gas produced during the earlier stages of decay.
- Male and female turkey vultures are
identical in appearance.
The "Turkey Vulture Society," dedicated strictly to Turkey Vultures, produces
a fine website with pages dealing with such topics as how to "adopt" a vulture,
and what to do if you find an injured one. You can visit it at http://vulturesociety.homestead.com.