The population in South Africa is limited.  This carrion/scavenging bird,  similar in value to Vultures have the following unusual adaptations.  1) They have hollow toes (aiding flight)  2) The hanging red air sack is connected to the left nostril and used during courtship and breeding  and facilitates a resonating croaking sound 3) They defecate on their legs  for cooling purposes  and 4) precede fires in order to consume animals/birds being disturbed.  They are often seen near refuse dumps and favour aquatic areas.