Animal Facts

Knobbed Hornbill

Scientific Name: Aceros cassidix

Fast Fact:

The knob on the hornbill’s head is known as a casque. The hollow structure is believed to help the hornbill produce its vocalizations, which are as unique as the knob itself. This hornbill’s sound can be very loud and resembles the bark of a dog. 

Knobbed Hornbill Pair

The knobbed hornbill is one of many species of hornbill found in Asia. It can be recognized by its bright colors around the face and the red or yellow knob on its beak. It is a fairly large bird and prefers to fly, living up in the canopies of tropical forests.

STATUS: The knobbed hornbill is listed as Least Concern by the International Union for the Conservation of Nature (IUCN), due to its large range. However, the population trend for this type of hornbill appears to be decreasing.

HABITAT: This species of hornbill is found primarily on Sulawesi as well as its neighboring islands, all within Indonesia. The birds inhabit the tropical forests found on these islands and prefer to live up in the trees.

DIET: The diet of the knobbed hornbill consists mainly of fruits and berries found in Indonesia. They will, however, occasionally eat insects and even some small animals.

PHYSICAL CHARACTERISTICS: The knobbed hornbill has a black body, a white tail and a knob on its beak. Its face is very colorful, containing several bright shades of blue around the eyes and a yellow beak. There are several distinctions between male and female knobbed hornbills. The male has a reddish-yellow neck while the female’s is black like the rest of the body. Also, the knob on the male’s head is red while the female’s knob is yellow and a bit smaller. Adult knobbed hornbills have four to eight folds on their casque, which can be used to help determine their age. 

Unusual Nesting

During breeding season, hornbills will pair off to build a nest. In order to keep their eggs safe, the female will enter the nesting hole in a tree and the male will then seal her in, using mud, saliva and anything else he can find. A small slit will be left open, through which the male will regurgitate food for the female and eventually for the hatchlings. This same hole is used by the birds inside to dispose of any food debris or excrement, in order to keep the nest as clean as possible. Usually after about three months, and once the male can no longer provide enough food, the female will break out to help him. The chicks will remain safely inside the nest until they are ready to emerge several weeks later. 

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