• Welcome to BirdForum, the internet's largest birding community with thousands of members from all over the world. The forums are dedicated to wild birds, birding, binoculars and equipment and all that goes with it.

    Please register for an account to take part in the discussions in the forum, post your pictures in the gallery and more.
ZEISS DTI thermal imaging cameras. For more discoveries at night, and during the day.

Knobbed Hornbill - BirdForum Opus

Revision as of 21:46, 4 September 2023 by Deliatodd-18346 (talk | contribs) (→‎External Links: New combined GSearch. GSearch checked template)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Alternative names: Butung Hornbill; Red-knobbed Hornbill; Sulawesi Wrinkled Hornbill; Celebes Wrinkled Hornbill

Rhyticeros cassidix


70-80cm. A large hornbill with a white tail and a high casque.


  • Black body
  • Deep rufous crown and nape
  • Paler rufous to creamy head sides and neck
  • Yellow bill with orange and brown ridged base, red wrinkled casque
  • Pale blue bare skin around eye
  • Dark blue and black bare throat skin


  • Smaller than male
  • Black head and neck
  • Yellow casque
  • Throat skin with only small black band

Juveniles like adult male but with a small, plain yellow bill without casque


Endemic to Sulawesi (Indonesia) and some adjacent offshore islands (Lembeh, Togian Islands, Muna and Butung).
Locally common.


Photo by martinuk
Dumoga Bone National Park, Sulawesi Utara, Indonesia, September 2009

This is a monotypic species.
May form a superspecies with Walden's Hornbill, Wrinkled Hornbill and Writhed Hornbill.
Formerly placed in genus Aceros.


Evergreen forest. Occurs up to 1800m.


The diet consists mainly of fruits and figs. Takes also some insects, bird eggs and nestlings.
Forages mainly in the canopy.
Breeding season starts June to September. The nest is placed in a natural hole in a large tree. The female sealed itself inside a tree hole for egg-laying. During this time, the male will provide foods for the female and the young. Raises usually one chick.


  1. Clements, J. F., T. S. Schulenberg, M. J. Iliff, D. Roberson, T. A. Fredericks, B. L. Sullivan, and C. L. Wood. 2015. The eBird/Clements checklist of birds of the world: v2015, with updates to August 2015. Downloaded from http://www.birds.cornell.edu/clementschecklist/download/
  2. Del Hoyo, J, A Elliot, and J Sargatal, eds. 2001. Handbook of the Birds of the World. Volume 6: Mousebirds to Hornbills. Barcelona: Lynx Edicions. ISBN 978-8487334306

Recommended Citation

External Links

GSearch checked for 2020 platform.1