Globally Vulnerable, Endangered in Namibia and Near-threatened in South Africa. Outside of protected areas it is largely reliant on the remnants of natural vegetation in agricultural land.
Among South Africa’s rarest breeding endemics, the Black Harrier Circus maurus has a global population of only about 1500 birds. It breeds only in South Africa, where its breeding grounds are centred on the coastal and montane regions of the Western Cape.
Over the last 9 years, FitzPatrick Institute researchers and students have studied its breeding requirements. After monitoring 150 nesting sites and over 250 breeding attempts we understand these requirements well.
Black Harriers breed most successfully in protected coastal areas where mouse numbers are high. Under such conditions, pairs raise on average two young per breeding attempt. The least successful breeding occurs in mountainous areas, where more than half of all nests fail and the average nest produces
only one fledgling. The reason for its rarity is shrinking habitats. More than 90% of the Cape lowlands have been transformed by agriculture. After breeding, many harriers move away from the breeding grounds, but we know not where. We also have no information about how many of them die (and why) during the non-breeding season. A successful pilot tracking study in 2008 has shown some unusual behaviours, such as regular night-time activity and, during the breeding season, foraging much farther from the nest (30-50 km) than previously appreciated.
This striking bird of prey breeds in the unique and incredibly diverse fynbos habitat of South Africa; a habitat which is threatened by the activities of humans. Adult black harriers have black plumage with bold white stripes across the tail, a white rump, and conspicuous white wing panels. Females are larger than males, and juveniles can be distinguished by their dark brown plumage, which is heavily mottled and streaked. The genus name of the black harrier, Circus, refers to the male’s circling, acrobatic flight display, undertaken to impress a female during courtship.
Largely resident, although it tends to head north and east from the Western Cape in winter.
It mainly eats mice and birds, doing most of its hunting on blustery days. It flies close to the ground, then speedily drops onto its prey, often giving chase on the ground before finishing the animal off. The following food items have been recorded in its diet: