The Price of Progress Comes Home to Roost
Tuesday, May 31, 2005
Like some squadron of death, the flesh-eating birds circled down from an unremarkable sky one day in April, and no one in Breton Bay knew quite what to do.
In more than a decade in the Southern Maryland neighborhood, Elaine Kramer had seen nothing like it: dozens of black vultures perched on rooftops and decks, all hunched shoulders and bald skulls. "Like a dive-bombing sequence," she said, they strafed her house with droppings. For weeks their hooked beaks tore caulking off her roof; their stomping could be heard through the ceiling.
When she pulled out of the garage, they were right there on the ledge, beady-eyed stares boring through her windshield. At one point, Kramer, the St. Mary's County finance director, stood in her driveway with her car door open, ready to jump in, and hurled tennis balls. The vultures were unfazed.
"It was incredible. When you look up and see 26 vultures lined up on the peak of your roof and some of them are sort of strutting around, it's pretty disconcerting," she said. "Hopefully it's not some seasonal migration pattern that we're going to have to get used to."
It very well might be. While a precise head count is not available, experts say the numbers of turkey and black vultures -- the region's two species -- have been booming in recent years. They are most noticeable when they congregate to roost before dispersing to breed.
Last year, the Audubon Society's Christmas bird count -- just a portion of what's out there -- recorded 14,955 black and turkey vultures in Maryland, Virginia and the District, up from 7,332 two decades earlier. Across North America, the number of turkey vultures roughly doubled between 1980 and 2000, while black vulture populations increased more than fourfold, according to federal officials.
Once based primarily in Central America and the gulf states, vultures are on a colonizing march up the Northeast: Maryland and Virginia now have the highest relative abundance of black vultures among 13 Eastern states.
Humans have in effect encouraged the vulture expansion with refuse and land clearing, biologists and federal officials said. As people have pushed new roads and houses farther out into the rural countryside, they've brought more roadkill and landfills to feed the vultures.
"The more land clearing you do, the better it is for vultures -- it makes it easier to find food," said Martin S. Lowney, Virginia director for the U.S. Department of Agriculture wildlife services program, which responds to the growing number of complaints of damage caused by vultures. "They're going to keep increasing at a fast rate."
Majestic fliers with a wingspan up to six feet, vultures have become notorious on farms, at marinas and on suburban streets. The turkey vulture prefers carrion, but the more aggressive black vulture will kill newborn calves, sheep or pigs. They can tear windshield wipers off cars and shred vinyl seats on boats; officials say that two dogs in Virginia have died of botulism from eating vulture vomit.
"This is not going away," said Bryan D. Watts, director of the Center for Conservation Biology at the College of William and Mary. "And what's clear, I think, is the conflict will continue to intensify until a resolution is forced."
Finding that resolution has been difficult. The vultures are federally protected under the 1918 Migratory Bird Treaty Act, though officials can issue permits to kill them. From 2000 to 2003, the number of vultures legally killed in Virginia rose from 142 to 450; in Maryland, from 2 to 20, according to a recent report from the Department of Agriculture. Environmentalists have criticized the killings. The birds don't breed until they are 8 years old and when they do, lay only two eggs per year, Watts said.