Cape vultures live together in large colonies, favouring layered sandstone and quartzite rock ledges as nesting spots and tell-tale fecal white-washed cliff sides make it easy to identify where Cape vultures are nesting. As their name would suggest, Cape vultures were once a common sight in the Western Cape, with colonies nesting on the cliff-sides of Cape Town’s Table Mountain, but as their numbers have dwindled, they have moved to the hilly terrain in the east of the country.
In the early mornings, vultures need the air currents found along cliff-sides to lift them into the air, but later in the day as the air heats and creates thermals, they can literally soar for hours with little effort as they scan the surroundings for food with eyesight eight times sharper than human 20/20 vision. Although they are scavengers and will eat rotting meat if they need to, vultures prefer their food fresh and as soon as a carcass is spotted will descend rapidly to start feasting, generally getting to the carcass before ground scavengers can. A flock of vultures feeding is a noisy occasion, with a fair amount of squabbling as they rapidly strip a carcass, storing the meal in their crops to digest later or regurgitate for chicks.
As Cape vultures (Gyps coprotheres) typically lay only one egg each year, their slow reproduction rate is a contributing factor in declining numbers. Moreover, scientists have noted that there is a prevalence of metabolic bone disease among Cape vulture chicks, likely caused by insufficient calcium intake. This is possibly due to fewer mammal predators such as lions and hyenas which would break up carcass bones with their strong jaws, thereby creating bone fragments which adult vultures would take to their chicks. Chicks suffering from calcium deficiency are unable to fly, falling to their deaths when they try to leave the nest. It is estimated that fewer than 50 percent of vulture chicks survive their first year of life.
Some measures being implemented to help vultures survive include educating the public about the important role they play in the ecology by cleaning up carcasses, and dispelling the myth that vultures are a threat to livestock. Although they are classed as birds of prey, vultures are not equipped to kill animals, particularly healthy animals. Feeding stations with crushed bones are being made available in some areas to address the calcium deficiency issue, and cultural superstitions linked to so-called magical properties of vulture body parts are being addressed where possible.
