Last September once again I missed International Vulture Awareness Day. That was on September 7 and my husband Bruce and I were celebrating our fiftieth wedding anniversary in the province of Quebec. Specifically, we were sitting six feet away from the largest common gannet colony in the Western hemisphere, watching them fighting, mating, tending young, and diving for food.
If only watching turkey vulture behavior on our mountain was as easy. Of course, I do see them sailing up and down Sapsucker Ridge most days from early March, when they return from their winter quarters, until mid-November when they are off again. We think we may have had a pair nesting somewhere on the talus slope because several years ago our son Dave saw an almost grown youngster sitting on the rocks.
Then, in the spring of 2012, our caretaker Paula Scott reported seeing a turkey vulture sitting the entire day on top of the deserted and wrecked home our late former neighbor Margaret McHugh. Paula watched the bird from her own home that had been built farther up the hill and looks down at the old place.
According to researchers, old, deserted homes and other buildings are favorite nesting places for turkey vultures. I was hopeful that I would finally be able to watch from Paula’s home (a natural blind) the domestic affairs of a pair of turkey vultures.
But it was not to be. Paula never saw any further sign of vultures near the house, and it was too dilapidated for us to climb up to the attic and check it out. Probably the close proximity of the Scotts’ home had discouraged the vultures if, indeed, they had been interested in nesting in the old house.
Maybe they nested in the talus slope instead or in the crevice of one of many fallen trees on our property. I only know that on September 24, a clear, breezy day, I was walking down First Field when I spotted a vulture sitting on a power pole at the base of Sapsucker Ridge. At first I thought it was a black vulture because it had a gray head. But so do immature turkey vultures and this one had a long tail, not the short one of a black vulture. Then a mature turkey vulture followed by a second and a third one soared close to the power pole vulture as if showing the youngster how to ride the wind as they do.
But the youngster paid no attention to the soaring vultures. Instead, it groomed itself. It also ignored me as I edged closer and closer. Even when I walked beneath the pole, shouted and clapped my hands, it didn’t budge. It didn’t even look down at me. Only an immature would be so oblivious to a human. I studied it for a long time, but it never did fly off. However, watching it had given me the chance to celebrate International Vulture Awareness Day a little late.
Even though our turkey vultures are the most widely distributed and abundant of all vulture species worldwide, ranging from southern Canada to the southern tip of South America and on large and small islands from Cuba and Puerto Rico to the sub-Antarctic Falkland Islands, many species have rapidly dwindling populations. For instance, three of south Asia’s vulture species lost 99 percent of their population in 25 years due to a veterinarian drug used on livestock that is toxic to vultures and five African species are gravely threatened by accidental and purposeful poisoning. Since most people don’t like vultures, they only learn after they lose them how invaluable they are in cleaning up dead creatures.
Hawk Mountain Sanctuary researchers have been studying turkey vulture migration behavior since the spring of 2003 by radio-tagging some and surgically implanting a data logger in the bodies of others which records core body temperature and heart rate. They also wing-tagged dozens of them in an effort to learn more about the extent, causes and consequences of their annual migration.
According to their website, their goals in monitoring New World raptors are to “routinely monitor seasonal populations of New World vultures in North, Central and South America, prevent catastrophic population declines by sharing learned information with conservation partners, and use black and turkey vultures as environmental sentinels of ecological change and environmental contamination, including climate change and heavy metal contamination..”
They have discovered that our subspecies of turkey vulture Cathartes aura septentrionalis is a partial migrant to as far south as Texas and southern Florida, although in February of 2010 Dr. Keith L. Bildstein and Lauriane Streit drove down the Delmarva Peninsula from Milford, Delaware to the Chesapeake Bay Bridge tunnel toll booth passing numerous chicken farms, each with its own flock of vultures, and called it “one of the biggest East Coast winter resorts for vultures.”
A longer drive along the coast found that there were more turkey vultures than black vultures, for example, on the Delmarva drive they counted 245 turkey vultures to 23 black vultures. But on counts in the Appalachian Mountain from northern West Virginia to North Carolina and Tennessee there were more black vultures than turkey vultures.
Bildstein wrote the turkey vulture section in the Second Atlas of Breeding Birds in Pennsylvania and reflects on the difficulty of finding turkey vulture nests, saying that up to 70 percent of a local population may not breed. Nevertheless, he has good news about their numbers. They have expanded in the Appalachian Plateau region of Pennsylvania from their former range in the more southerly part of the state and have shown a 13 percent increase in breeding blocks from those reported in the first Pennsylvania breeding bird atlas project back in 1983-89. The Breeding Bird Survey also reported a 50 percent increase in turkey vultures between 1966 and 2009. Migration hawk watches throughout the state similarly have observed an increase in turkey vulture migrants.
Bildstein believes that the increase is due to several factors: the increasing numbers of wildlife including white-tailed deer that are killed on highways and decreased persecution of them by humans. While most Pennsylvanians may not care that much for turkey vultures, apparently they appreciate their role as nature’s scavengers, cleaning up not only dead wild animals but domestic ones as well.
Using their keen sense of smell to help locate food, they feed on carrion without getting much gore on their naked heads. No doubt, this reduces their exposure to bacteria, parasites, and disease. Still, in his “Vulture Chronicles,” an absolutely delightful ongoing account on the Hawk Mountain Sanctuary website by Bildstein and other researchers of their work with vultures, not only in the Western Hemisphere but in the Eastern one as well, he writes that they still are threatened by “high levels of toxic chemicals in human habitations (including human drugs in urban areas, and agricultural pesticides in farmlands)…” In addition, they often fly into transmission lines while searching for carrion with their heads pointed down. They may also crash into vehicles. Because they feast on dead and dying birds and human garage they are exposed to “veterinarian drugs and antibiotics that contaminate the carcasses of domestic livestock and heavy metals that contaminate our dumping grounds.” Those that feed on such food Bildstein calls “human-subsidized” vultures and cites several incidences in North and South America of turkey vultures zeroing in on humans at campgrounds and other places where they might get human leftover food.
That brings me to a poem by Hilaire Belloc written in 1897 for his book More Beasts for Worse Children which says:
The Vulture eats between his meals,
And that’s the reason why
He very, very, rarely feels
As well as you and I.
His eye is dull, his head is bald,
His neck is growing thinner.
Oh! What a lesson for us all
To only eat at dinner!!
All photos by Dave Bonta.