Rhabdotorrhinus corrugatus (Temminck, 1832)

Common Name and Range

The wrinkled hornbill, also called the Sunda wrinkled hornbill (Rhabdotorrhinus corrugatus), is a medium-large hornbill that inhabits forests in the Thai-Malay Peninsula, Sumatra, and Borneo.

Body Size and Bill Structure

It is roughly 70 cm long, with a very large bill that is fused to the skull.

Plumage and Markings

It has mostly black plumage, a blue eye-ring, and a tail with a broad white or rufous tip.

Sexual Dimorphism Overview

Males and females have different head and bill patterns.

Male Plumage

Males have bright yellow feathers on the auriculars, cheeks, throat, neck sides, and chest; these areas are black in females, with the exception of a blue throat.

Male Bill and Casque

The male’s bill is yellow, with a red base and red casque, and a brownish basal half on the lower mandible.

Female Bill and Casque

The female’s bill and casque are almost entirely yellow.

Diet

This is a forest-dwelling species that feeds mainly on fruit, such as figs, though it also eats small animals including frogs and insects.

Water Intake

Wrinkled hornbills do not drink, and instead get all the water they need from their food.

Vocalizations

Their call is a harsh "Kak-kak", or a deep "Row-wow" that can be heard for miles.

Mating System

These birds are monogamous and pair for life.

Nest Location

They nest in natural tree holes.

Nest Entrance Preparation

The female plasters over the nest entrance with mud and droppings, leaving only a small opening that is too small for the nesting female and her chicks to exit through.

Nest Feeding Behavior

The female and chicks are fed exclusively by the male, who regurgitates food for them.

Nest Departure

When the chicks are ready after several months, the female breaks out of the nest.

Captive Breeding Record

The first successful captive breeding of wrinkled hornbills occurred in 1988.

Conservation Status

Heavy deforestation of their forest habitat led to this species being uplisted from Near Threatened to Endangered on the IUCN Red List in 2018.