Helmeted hornbill (Rhinoplax vigil)
The largest hornbill in Asia (5), the helmeted hornbill (Rhinoplax vigil) is named for its bizarre ‘casque’, a protuberance which perches, helmet-like, on the upper half of the red and yellow, chisel-like bill (2). Unlike the casques of other hornbill species, which are typically hollow and extremely light, the casque of the helmeted hornbill is a solid block of an ivory-like substance (5).
The helmeted hornbill has dark brown upperparts and white underparts (2). Its extremely long central tail feathers, which often double the length of the entire bird, are white with dark banding patterns (3), and there are chestnut-brown feathers around the eyes (5).
Both male and female helmeted hornbills have a bare, featherless patch on the neck. This leathery skin is red in males and turquoise in the smaller females (2).
The peculiar call of the helmeted hornbill is described as a series of hollow ‘took ’notes followed by maniacal laughter, which is unique to this species (3).
The helmeted hornbill is thought to be a territorial bird. Small groups of up to 14 non-breeding and immature birds may forage for food within a single area, but adult breeding pairs have their ownterritories (2).
The helmeted hornbill performs incredible displays in flight, in which individuals collide in mid-air, theircasques clashing with a loud ‘clack’. This aerial jousting, which usually takes place between two males, often results in one or both hornbills being flung backwards, before righting themselves again in flight. These collisions are typically observed near fruiting fig trees, suggesting that the birds are fighting over access to their favoured food (5).
The main food of the helmeted hornbill is fruit, with figs being a particular favourite. However, this species also feeds on small animals, including mammals, snakes, and even smaller hornbills. It typically forages high up in the forest canopy, where it can sometimes be seen hanging upside-down, digging under the bark with its heavy beak and casque. Although breeding pairs share a territory, the male and female forage independently (2).
All hornbills are noted for their bizarre nesting habits, in which the female is sealed within a hollow tree toincubate the eggs (2). A nest is created within a natural hollow, high in a tree, and the female is then sealed within the hollow with mud by the male (2) (3). Only a small hole is left, through which the male passes the female regurgitated food, while the female incubates the eggs (2). The helmeted hornbill has been observed to lay eggs in January to March, as well as in May and November (2). When the young have hatched, the female breaks out of the hollow, then reseals the entrance until the young have fledged (3).
read more at the source page