Thursday, June 21, 2007
A beak for dead meat
Ol' timey naturalists maintained that weasels commonly use creek beds as thoroughfares. I've seen them following small creeks in the Rockies, so I decided to camera trap a weasel in a dry creek choked with vegetation.
I baited a fallen log with a couple of mouse carcases, and doused it with predator scent -- a commercial concoction that would gag a maggot.
It was wishful thinking. There was no weasel in the neighborhood, but two days later a turkey vulture arrived. It was a remarkable feat of detection. I don't know if the vulture's cue was the sight or smell (or both), but the bird polished off the meager meal, and the camera captured the gourmet moment.
Afterwards, the vulture spent 5 minutes studying the ground beneath the perch. Or perhaps it was admiring its feet. I'm not sure.
Vultures are remarkable birds. Drs. David Houston and Kenneth Stager showed conclusively that turkey vultures have good noses. Until then it was assumed that birds in general do not have the gift of olfaction. The stench of decomposing animals however is a powerful attractant to mammalian scavengers, and the ancestral turkey vulture must have developed this sense early in its evolution to be competitive. The evolutionary scenario is believed to have been forested habitats where vision alone was not sufficient for vultures to 'bring home the bacon'.
My own experience with vultures is limited to the black vulture, which is less gifted than the turkey vulture as a glider and sniffer of decomposing flesh. Vernon appeared as an unidentified egg in a large aviary at the National Zoo in Washington, D.C. in the mid-1970s. He was hand-reared and transferred to the barracks building at the zoo's Conservation & Research Center, where most of the bird collection was held during renovation of the zoo's bird house.
Vernon's intelligence quickly earned him liberties that would never be granted to other birds in the collection. He had a quiet confidence. There was just something about the way he cocked his head and studied you that set him apart. He also had a foot fetish -- a beguiling way of shaking his beak at your shoes before he untied the laces. There was an unbird-like intelligence in the wrinkled head that resembled a charred bratwurst.
Before long the keepers let him out of the building, which immediately caused a stir in the administration. But it wasn't a problem. He flew around the buildings and studied the staff's activities from the rooftops, but he spent most of his time hanging around the barracks building, perched on the railing near the back steps, waiting for his daily pan of thawed white mice.
Vernon's boldness grew with his familiarity of the surroundings, and though his offenses drew criticism, his popularity always outweighed his misdeeds. As parents ignore a nose-picking child, we weren't blinded to his virtues by his bad breath and habit of crapping on his legs.
The daily Vernon report became a source of great entertainment, and his food-snatching technique in particular became legendary. He would show up at a Saturday afternoon barbecue like a weary traveler, and amble about with an air of boredom. When the chef was no longer paying attention he would flap up to the grill, snatch the steak, and disappear into the wild blue yonder. He was also seen to eat balloons and drink paint, worrisome feats that we learned had no physiological side effects.
When wild vultures started to show up, we learned that Vernon was a leader among his kind. One morning as I walked to work, I met Vernon sitting on the lawn. I extended my foot with kind words of encouragement, and he 'did his thing'. When I reported the story to Guy Greenwell, our bird curator, he informed me that it couldn't have been Vernon. Vernon had been locked up for bad behavior. A wild vulture had diddled my shoes, and only Vernon could have been its teacher. I believe it was about this time that Vernon revealed a long-kept secret. He laid an egg!
For all of her faults Vernon performed a final service to the institution. There was this traveling salesmen, one of our vendors, who was smitten with our adminstrative officer. From the era of blue-suede shoes, he was one of those smarmy country boys who wore plaid pants and mustard-yellow sports jackets, and he drove a humongous road hog with pleated and rolled upholstery. Got the picture?
It was one of those still summer days. The air conditioners were humming, the cicadas were buzzing, and Mr Slick had long overstayed his welcome in the office. Vernon had been casting about looking for stimulation when she found the plush upholstery in the road hog. The windows were open. She made herself at home and started to disembowel the front seat.
She has made respectable progress when Mr Slick finally went to his car and witnessed Vernon's clamorous escape.
What you need to know is that a startled vulture jettisons all extra baggage before take-off. That's right . . . it defecates and regurgitates.
Mr Slick couldn't believe his bad luck, and his insurance agent laughed him out of the office when he tried to collect for damages.
It was a long time before he came back, and when he did, his office visits were brief.
Vultures are remarkable birds.