Black vultures, recognizable by their dark plumage and bald heads, are increasingly common across parts of North America, particularly in the southeastern United States, with their range expanding northward into the Midwest. These birds often gather in large numbers, leading many to question if their presence poses a danger to domestic animals or human property. This article explores black vulture behaviors and potential risks.
Understanding Black Vulture Behavior
Black vultures (Coragyps atratus) are primarily scavengers, consuming carrion. They play a significant role in ecosystems by consuming carcasses, preventing disease spread. While they prefer large carcasses, they are opportunistic feeders and consume various food sources, including discarded food, fruits, and even turtle eggs.
These birds are highly social, often observed in large groups, particularly around food sources or communal roosting sites. Black vultures typically locate food visually, observing the movements of other scavengers like turkey vultures, which possess a stronger sense of smell.
Black vultures are not inherently aggressive towards humans. Their search for food and roosting locations sometimes leads to interactions with human environments. Their large communal roosts are found in various habitats, including open areas with scattered trees, and increasingly in suburban and urban settings.
Risks to Animals
While black vultures primarily feed on carrion, they have been documented attacking live animals, particularly vulnerable livestock. Newborn calves, lambs, and piglets are most susceptible, with attacks occurring during or shortly after birth. These predatory behaviors target eyes and other soft tissues of young or weak animals, leading to severe injuries that often necessitate euthanasia.
Black vultures exhibit mobbing behavior, where multiple birds collectively overwhelm an animal. This coordinated attack can be devastating to young animals, even healthy but defenseless ones without maternal protection. Reports of black vulture attacks on livestock have increased, particularly in states like Missouri, Virginia, and Kentucky, as their population and range expand.
The economic impact on livestock producers can be substantial, with losses averaging around $1,000 per calf. While direct observations of attacks are uncommon, evidence suggests black vultures can act as predators when the opportunity arises. Small domestic pets, though less frequently reported, could also be at risk if unsupervised in areas with active black vulture populations.
Property and Vehicle Concerns
Beyond risks to animals, black vultures can cause damage to human property and vehicles. Large groups roosting near homes or commercial buildings may tear at materials such as window caulking, roof shingles, vent seals, rubber roof liners, and pool covers. This behavior is attributed to curiosity or their search for nesting materials, rather than malice.
Vehicles are also susceptible to damage; black vultures scratch paint, remove rubber seals and windshield wipers, and rip vinyl seat covers from boats and tractors. Their acidic droppings and vomit can corrode roofing materials and accumulate on structures, potentially leading to costly repairs and power outages if roosts are on electrical transmission towers. This tearing behavior is linked to foraging instincts; once one vulture starts, others often join, amplifying destruction.
Coexisting with Black Vultures
Black vultures are protected under the Migratory Bird Treaty Act of 1918; harming them, their nests, or eggs is illegal without a federal permit. Lethal control typically requires a depredation permit from the U.S. Fish and Wildlife Service, often obtained after non-lethal methods are attempted and documented. Permits may allow for the removal of a limited number of birds, up to five per year for livestock producers.
Various non-lethal deterrence methods manage black vulture presence. Hazing techniques include loud noises from air horns, propane cannons, or pyrotechnics, and spraying with water. Visual deterrents, such as effigies—replicas of dead black vultures hung upside down with wings spread—are highly effective in scaring birds from areas like calving pastures.
Exclusion methods involve blocking perching areas or using structural deterrents to make roosting sites uncomfortable. Good animal husbandry practices, such as keeping vulnerable livestock penned near human activity during birthing season and promptly disposing of carcasses or afterbirth, reduce attractants. While black vultures can be a nuisance, understanding their behaviors allows for effective, lawful management strategies to minimize conflicts.