Rhinoceros Hornbill
Buceros rhinoceros
Majestic and stately inhabitant of mature lowland and foothill forests. Pitch black with a white tail marked by a single dark bar. Enormous bill is bright orange with a prominent casque that is short and rectangular in females, long and upswept in males. Often seen in powerful flight over forests, typically in pairs or small groups. Gives low, resonant calls, usually in series: either a single-syllabled “rohh” or a disyllabic “roh-ow.”
Identification
The rhinoceros hornbill is a large arboreal hornbill, 80 to 90 cm (31–35 in) long. The weight varies by sex, with males weighing around 2,465 to 2,960 g (87.0–104.4 oz) and the females 2,040 to 2,330 g (72–82 oz). The plumage is predominantly black, with white legs and vent and a white tail with a black band. The huge bill and casque are orange and red, the colour coming from preen oil rubbed on from the preen gland above the tail. The eyes of the male are red with black rims, and white with red rims in the female.
Taxonomy
The rhinoceros hornbill was formally described by the Swedish naturalist Carl Linnaeus in 1758 in the tenth edition of his Systema Naturae. He placed it with the great hornbill in the genus Buceros and coined the binomial name Buceros rhinoceros. Linnaeus specified the location as China. The genus name is from Latin becerus meaning "horned like an ox" which in turn is from the Ancient Greek boukerōs which combines bous meaning "ox" with kerōs meaning "horn". The specific rhinoceros is Latin for "rhinoceros".<p>Three subspecies are recognised:
- Scientific name
- Buceros rhinoceros
- Authority
- Linnaeus, 1758
- Order
- Bucerotiformes
- Family
- Bucerotidae
- Genus
- Buceros
Range and habitat
- Migration
- Resident species
Behavior
The diet of the rhinoceros hornbill is dominated by fruit, but it will take any insect, small reptile, rodent, and smaller birds that it can catch.<p>The courtship and bonding of these birds are critical, as the female must trust the male to provide her with everything when she is incubating and raising chicks. These hornbills make their nests inside tree trunks, and the female stays inside with the eggs and then with the chicks, while the male brings them food. After the eggs are laid, the male collects mud, and the pair pack that mud, along with food and feces, to wall up the entrance to the tree cavity. They leave a very small hole, just large enough for the male to feed the female, and later the chicks, and for the female to defecate through the hole. Once the chicks are fully feathered and old enough to leave the nest, the parents chip away the dry mud to let the chicks out.
Conservation
The rhinoceros hornbill faces a number of threats, including loss of its rainforest habitat, as well as hunting for its meat, and its skull and feathers. Habitat destruction has led to the loss of the large trees the species requires for breeding, which in turn makes it easier for poachers to find the rhinoceros hornbill. It is frequently shot at by poachers due to confusion with the highly sought-after helmeted hornbill. Due to this, the species was uplisted to vulnerable from near threatened on the IUCN Red List in 2018.
- Population trend
- declining
Photos
Distribution
Bird Calls
Other Birds
Gray Wren-Warbler
Calamonastes simplex
A very dark, long-tailed warbler of dry country. Blackish-gray overall with a reddish eye and white tips to the tail. With a good look, barring on the throat, belly, and vent may be visible. The tail is frequently cocked up. Generally common in dry thorn savanna and thornscrub. Usually stays in the understory, but will sing from the tops of bushes and small trees. Similar in shape to Miombo Wren-Warbler, but much darker, with virtually no overlap in range. The main vocalization is a loud “chup,” repeated about once per second.
Black-billed Thrush
Turdus ignobilis
A drab thrush, common in open habitats and woodlands in the lowlands but also wanders up into Andean foothills. Nondescript grayish-brown with a pale whitish belly. Note indistinct streaking on throat; some populations also show a white patch on chest. Sexes similar. Usually seen singly or in pairs. Conspicuous. Song is a typical thrushlike series of musical phrases.
White-lored Gnatcatcher
Polioptila albiloris
Tiny gray and white bird with cocked tail. Common in tropical dry forest and scrub of Pacific lowlands. Male has a black cap, solid in breeding season, but with narrow white eyebrow in non-breeding season. Female has gray cap with narrow white eyebrow year-round. Told from Blue-gray Gnatcatcher by face pattern: Blue-gray has a white eyering, not a white brow.
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