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Tuesday, 2 July 2019

26-5-2019 SOMALISA CAMP, ZIMBABWE - KALAHARI YELLOW BILLED HORNBILL (Tockus leucomelas ssp. leucomelas)


The Southern Yellow-billed Hornbill, known scientifically as Tockus leucomelas, is a medium-sized bird, with a length ranging from 48 to 60 centimeters and a weight between 132 and 242 grams. Its most striking feature is the long, down-curved yellow beak, which is disproportionately large compared to its body, making up to one-sixth of its body length. Males boast a longer beak, averaging 90 millimeters, while females have a slightly shorter one, averaging 74 millimeters. The species exhibits sexual dimorphism, with males generally larger than females. The bird's plumage is a combination of white, grey, and black, with the white belly and grey neck contrasting against the black back adorned with white spots and stripes. The eyes are typically yellow, though brown variations exist, and the skin around the eyes and malar stripe is pinkish.

To identify the Southern Yellow-billed Hornbill, look for the long yellow beak and modest-sized casque that covers almost the entire length of the beak in males. The bird's white belly, grey neck with spots, and black back with white markings are also distinctive. The male's larger size and longer beak are reliable indicators for sex differentiation in the field.


This hornbill species is a common and widespread resident of the dry thornveldt and broad-leafed woodlands, often seen along roads and watercourses. They show a preference for acacia and broadleaved woodlands when available.

The Southern Yellow-billed Hornbill is near-endemic to the dry savannas of southern Africa, with its range extending from Angola and Namibia in the west to Mozambique and KwaZulu-Natal in the east, including Botswana, Zimbabwe, and northern South Africa.

Active during the day, these birds are often solitary, but may form couples or small groups, especially during breeding or nesting seasons, or when local migration occurs during the dry season. They are ground foragers, not digging but rather overturning debris to find food. They are sedentary but may roam in search of sustenance during dry spells. Monogamous pairs defend their territories with elaborate displays.

The Southern Yellow-billed Hornbill's vocal repertoire includes a piercing cry, whistles, grunts, and cackles. These calls are used for territory demarcation and long-distance communication, often accompanied by physical displays.

Their diet consists mainly of arthropods like termites, beetles, larvae, grasshoppers, and caterpillars, supplemented by small mammals, berries, fruits, nuts, and eggs from other species. They use their beak as forceps to grasp and toss food into their throat, with serrated inner edges aiding in crushing and fragmenting their prey.