Edwin Giesbers / White-crowned hornbill (Aceros comatus) head portrait, captive

Chien Lee / White-crowned Hornbill (Berenicornis comatus) male, Gunung Mulu National Park, Malaysia

Tim Laman / African crowned hornbill (Tockus alboterminatus) perched in the forest canopy, Kibale National Park, Uganda

Mike Read / African crowned hornbill {Tockus alboterminatus} perched in tree, Umfolozi Game Reserve, South Africa