Black vultures have become an invasive species in Arkansas over the past 15 years as they've extended their range throughout the state, a wildlife services supervisor with the U.S. Department of Agriculture said.
"They've gone from being a rare species to a very common species year-round," said Michael Hoy, district supervisor for the wildlife services program in the USDA's Animal and Plant Health Inspection Service near Stuttgart.
Hoy said he has no estimates for the black vulture population in Arkansas, but the number of complaints about them has increased fivefold in 15 years.
Hoy said his office received 12 requests for assistance with black vultures in 2000. This year, the number was 70.
Many of those complaints have come from cattle farmers who say black vultures kill newborn calves.
"The black vultures swarm the calf in a group, then peck at the calf's eyes, or at the nose or the tongue," said Tom Troxel, professor and associate head of the animal-science department at the University of Arkansas' Agriculture Division in Little Rock. "The calf then goes into shock and is killed by the vultures."
The mission of the wildlife services program is to provide federal leadership in managing conflicts with wildlife.
An invasive species is "one that is not native to an ecosystem and which causes, or is likely to cause, economic or environmental harm or harm to human health," according to the U.S. Fish and Wildlife Service.
There are about 20 million black vultures globally and about 1.8 million in the United States, according to the Partners in Flight databases, managed by Rocky Mountain Bird Observatory.
Every year in September and October, thousands of black vultures arrive in Arkansas from the southeast. Their range extends through much of Mexico and South America.
Turkey vultures, which have a distinctive red head, are native to Arkansas, Hoy said. There are about 18 million turkey vultures globally and 5 million in the United States, according to Partners in Flight.
Black vultures are more aggressive than turkey vultures, which almost never attack living prey.
Forrest Wood of Flippin said black vultures kill one or two of his calves every year, and this has been happening for about a decade.
"Turkey buzzards never hurt anything," said Wood, who is the founder of Ranger Boats. "They just clean up dead carcasses.
"Black vultures, however, are the opposite. They are not native to our area. They destroy a great deal of property such as house roofs, plastic car and Jeep parts and outdoor lawn furniture or equipment. One of our houses had a vulture down a chimney while they were destroying the roof, and the fireplace had to be taken apart to remove the buzzard."
If the vultures don't peck a calf's eyes out, Wood said they disturb the mother cow to the point that she ends up trampling the newborn. Calves are worth about $1,000.
"The answer to the vulture problem is eradication," Wood said.
But vultures are a protected species under the Migratory Bird Treaty Act, so they can't be killed legally without permission from the federal government.
According to the International Union for Conservation of Nature and Natural Resources, black vultures are listed in the category of "least concern" on its list of threatened species.
Black vultures will never be removed from protection under the Migratory Bird Treaty Act, even though their numbers have increased significantly, said John Klavitter, national invasive-species coordinator with the Fish and Wildlife Service's National Wildlife Refuge System in Falls Church, Va..
"Nobody in this country can shoot a migratory bird without a permit," Klavitter said. "So that's most of the native birds in North America, even if they seem abundant and they seem a pest."
However, Wood got a depredation permit from the U.S. Fish and Wildlife Service, which allows him to kill vultures on his property. The first point of contact for Arkansans to get such a permit is Hoy's office.
It's a remedy of last resort. Vultures have an aversion to dead of their own species, so Wood shot a few and hung the dead birds up. That made the live vultures leave his pasture, but he said his display only may have chased to them to another part of his farm or to a neighbor's farm.
Rob Hall of Mountain Home said black vultures have killed about 15 of his calves over the past eight years.
"Of all the predators for a cow/calf operation, they are probably the most profit-losing thing that you've got against you right now," Hall said.
When the vultures are on his property, which is usually worse in the spring, Hall said he can't leave if a cow is about to give birth. He has to be there to watch over the calving and make sure both the cow and calf are protected.
Kert Marrs of West Fork, who has a farm near Goshen, said he's had a problem with black vultures for about five years. They've killed two of his calves.
"I've had to be a lot more vigilant since we've had this problem over the last four or five years," Marrs said. "I've run them off several times. During calving, you have to run them off."
According to the Cornell Lab of Ornithology, black vultures were tolerated around meat markets in the southeastern United States in the 19th century because they were considered beneficial scavengers.
That attitude changed in the early 20th century, when some people became concerned about vultures spreading disease -- despite a lack of scientific evidence.
"Vultures were trapped, poisoned and shot by the thousands until the 1970s," according to the Cornell lab's website, allaboutbirds.org.
Other factors through the mid-20th century also caused the number of black vultures to decrease, but black vultures have rebounded and expanded their range in the U.S. to the north and east in recent years.
"This is probably due in part to increasing availability of roadkill and warmer weather associated with global climate change," according to Cornell's website.
The carrion diet of black vultures includes the remains of feral hogs, poultry, cattle, donkeys, raccoon, coyotes, opossums, skunks and armadillos, according to the Cornell lab. Sometimes black vultures wade into shallow water to feed on floating carrion or to catch small fish.
"They occasionally kill skunks, opossums, night-herons, leatherback turtle hatchlings and livestock, including young pigs, lambs, and calves," according to Cornell. "They also often investigate dumpsters and landfills to pick at human discards."
Tom MacKenzie, a spokesman for the U.S. Fish and Wildlife Service in Atlanta, said the number of farmers' complaints about black vultures has been growing steadily. But not all the complaints are from farmers.
"In Florida, they chew on sailboats and cars," MacKenzie said. "They like windshield wiper blades. They're kind of like squirrels in that they like to chew on stuff."
Rebecca McPeake, a professor of wildlife extension with the UA Agriculture Division , said complaints have increased in the 15 years that she's been working there.
"In recent years, it has been more than just occasionally," she said. "We have received more and more reports on this issue."
Killing four black vultures and hanging the carcasses around Bull Shoals Dam worked for the U.S. Army Corps of Engineers -- at least temporarily. The Corps got a permit and had four vultures killed in June. Bull Shoals Dam is 15 miles west of Mountain Home on the White River.
Metro on 10/11/2015
Print Headline: Farmers in state fear for calves as black-vulture flocks thrive