Although a common and widespread species, it has a somewhat more restricted distribution than its compatriot, the turkey vulture, which breeds well into Canada and all the way south to Tierra del Fuego.

These features are all evolutionary adaptations to life as a scavenger; their black plumage stays visibly cleaner than that of a lighter-colored bird, the bare head is designed for easily digging inside animal carcasses, and the hooked beak is built for stripping the bodies clean of meat.

It lays its eggs in caves, in cliffside rock crevasses, dead and hollow trees, or, in the absence of predators, on the bare ground, generally raising two chicks each year.

[4] The German ornithologist Johann Matthäus Bechstein formally described the species using the same name in 1793 in his translation of John Latham's A General Synopsis of Birds.

[5][6] The common name "vulture" is derived from the Latin word vulturus, which means "tearer" and is a reference to its feeding habits.

[16] Martin Lichtenstein described C. a. foetens, the Andean black vulture, in 1817, and Charles Lucien Bonaparte described C. a. brasiliensis, from Central and South America, in 1850 on the basis of smaller size and minor plumage differences.

This bird did not differ much from the black vulture of today except in size; it was some 10–15% larger and had a relatively flatter and wider bill.

[21] It filled a similar ecological niche as the living form but fed on larger animals,[22] and was previously thought to have evolved into it by decreasing in size during the last ice age.

[23][24] However, a 2022 genetic study found C. occidentalis to be nested within the South American clade of black vultures; C. occidentalis had evolved from the modern black vulture about 400,000 years ago and developed a larger and more robust body size when it colonized high-altitude environments.

[25] C. occidentalis may have interacted with humans; a subfossil bone of the extinct species was found in a Paleo-Indian to Early Archaic (9000–8000 years BCE) midden at Five Mile Rapids near The Dalles, Oregon.

[26] Fossil (or subfossil) black vultures cannot necessarily be attributed to the Pleistocene or the recent species without further information: the same size variation found in the living bird was also present in its larger prehistoric relative.

[27] The southern birds were of the same size as present-day northern black vultures and can only be distinguished by their somewhat stouter tarsometatarsus and the flatter and wider bills, and even then only with any certainty if the location where the fossils were found is known.

It is known to regurgitate when approached or disturbed, which assists in predator deterrence and taking flight by decreasing its takeoff weight.

[37] It cools the blood vessels in the unfeathered tarsi and feet, and causes white uric acid to streak the legs.

[34] The stance is believed to serve multiple functions: drying the wings, warming the body, and baking off bacteria.

In the United States, birds in Florida begin breeding as early as January, while those in Ohio generally do not start before March.

[32] In South America, Argentinian and Chilean birds begin egg-laying as early as September, while those further north on the continent typically wait until October.

Some in South America breed even later than that—black vultures in Trinidad typically do not start until November, for example, and those in Ecuador may wait until February.

[32] Pairs are formed following a courtship ritual which is performed on the ground: several males circle a female with their wings partially open as they strut and bob their heads.

The smooth, gray-green, bluish, or white shell is variably blotched or spotted with lavender or pale brown around the larger end.

[49] In areas populated by humans, it may scavenge at garbage dumps for refuse, offal, and other discarded edible waste, but also takes eggs, fruit (both ripe and rotting), fish, dung and ripe/decomposing plant material and can kill or injure newborn or incapacitated mammals.

It occasionally harasses cows giving birth, but primarily preys on newborn calves, lambs, and piglets.

[57] Black vultures have sometimes been observed removing and eating ticks from resting capybaras and Baird's tapir (Tapirus bairdii).

Anti-microbial agents may be secreted by the liver or gastric epithelium, or produced by microorganisms of the normal microbiota of the species.

[63] In the United States it is illegal to take, kill, or possess black vultures without a permit and violation of the law is punishable by a fine of up to US$15,000 and imprisonment of up to six months.

Populations appear to remain stable, and it has not reached the threshold of inclusion as a threatened species, which requires a decline of more than 30% in ten years or three generations.

"[67] The bird can be a threat to the safety of aerial traffic, especially when it congregates in large numbers in the vicinity of garbage dumps[68]—as is the case in the Rio de Janeiro Tom Jobim International Airport.

[69] The black vulture can be held in captivity, though the Migratory Bird Treaty Act only allows this in the case of animals which are injured or unable to return to the wild.