These are large vultures, noticeably outsizing the closely related white-backed vulture, with which they often co-occur in the wild. Adults are 85 to 103 cm (33 to 41 in) long, with a wingspan of 2.26 to 2.6 metres (7.4 to 8.5 ft), and a weight that ranges from 6.4 to 9 kg (14 to 20 lb). Both genders look alike: mottled brown or black overall with a whitish-brown underbelly and thin, dirty-white fluff covering the head and neck. The base of the neck has a white collar, the eye is yellow or amber, the crop patch deep brown. Silent as a rule, they become vocal at their nest and when at a carcass, squealing a great deal.
Rüppell's vultures are very social, roosting, nesting, and gathering to feed in large flocks. Their range extends through the Sahel region of Africa where they can be found in grasslands, mountains, and woodlands. Once considered common in these habitats, the Rüppell's vultures are experiencing steep declines, especially in the Western portion of their range. They are relatively slow birds, cruising at 35 kilometres per hour (22 mph), but fly for 6–7 hours every day and will fly as far as 150 kilometres (93 mi) from a nest site to find food.
Rüppell's vultures commonly fly at altitudes as high as 6,000 metres (20,000 ft). The birds have a specialized variant of the hemoglobin alphaD subunit; this protein has a great affinity for oxygen, which allows the species to absorb oxygen efficiently despite the low partial pressure in the upper troposphere. A Rüppell's vulture was confirmed to have been ingested by a jet engine of an airplane flying over Abidjan, Ivory Coast on November 29, 1973 at an altitude of 11,300 m (37,000 ft). During August 2010 a Rüppell's vulture escaped a bird of prey site in Scotland, prompting warnings to pilots in the area to watch carefully due to the danger of collision.
Rüppell's vultures have several adaptations to their diet and are specialized feeders even among the Old World vultures of Africa. They have an especially powerful build and, after the most attractive soft parts of a carcass have been consumed, they will continue with the hide, and even the bones, gorging themselves until they can barely fly. They have backward-pointing spines on the tongue to help remove meat from bone. Despite their size, power and adaptations, they are not the most dominant vulture in their range, which is considered to be the even larger lappet-faced vulture.
This species of vulture is considered to be monogamous, forming lifelong breeding pairs. After courtship the pair will work together to build a nest using sticks, grass, and leaves that they have gathered or stolen from other nests. Rüppell's vultures build these nests on cliffs, and in key breeding areas they are known to nest is large colonies containing hundreds of breeding pairs. Both parents share in incubation of their egg over a period of 55 days. Once the chick hatches, both parents will feed and tend to it for about 150 days when it fledges. Young remain dependent on their parents after fledging, not reaching independence until the next breeding season. During this time they learn how to find and compete for food.
Rüppell's vulture populations are experiencing declining populations throughout their entire range. These declines can be attributed to loss of habitat related to human-related land use, poisoning, human use for medicine or meat, loss of nesting sites, and declining availability of food sources. Poisoning is currently thought to be the most serious threat to all vulture populations in Africa, although they are not usually the intended target. In events where predators such as lions or hyenas have killed livestock, Carbofuran poisons have been placed into carcasses as retaliation against the predators. Unfortunately, vultures utilize carrion as their main food source and one carcass has the potential to attract hundreds of birds to feed because this species identifies food by sight. One evaluation of 10 poisoning events found that each event caused the death of 37 to 600 individuals.
Killing of Rüppell's vultures for use in medicine has also greatly contributed to the rapid population decline. In many African cultures, vultures are used for medicine and magic related to superstitions that they are clairvoyant and can be used to increase a child's intelligence. Establishing protected wildlife areas is thought to be an effective route to protect the Rüppell's vulture from extinction. The Rüppel's vulture breed and nests in cliffs in Northern and Southern Kenya, as well as Tanzania. These breeding and nesting grounds amass huge numbers of Rüppell's vultures which will raise young and forage in the surrounding area. Considering that the detection rate of Rüppel's vultures was found to be lower in protected areas than outside of them, extending protection to these key breeding sites could help support their population.