This aerial hunter feeds primarily on rodents, small birds and the occasional reptile (7), but also eats eggs, insects and, very occasionally, carrion (2). The black harrier soars low over the vegetation searching for prey, often hovering before plunging down to seize its meal (2).
Like other harriers, the black harrier makes an undulating courtship flight which precedes mating (2). Black harriers breed mainly in the wet season, and have been recorded laying eggs from July to September. Three to four pairs may nest close to one another (2), each building an untidy nest of grass at the base of stems, reeds or weeds (2). The three to four eggs that are laid are incubated for around 34 days, and the chicks fledge after 36 to 41 days (2). In winter, black harriers migrate north to the dry steppe and grassland habitats of southern Namibia, southern Botswana and southern Transvaal (2).