https://phys.org/news/2018-05-helmeted-hornbill-falls-silent.html

Back in England, a playback of this ridiculous call was the highlight of every rainforest talk that I inflicted on schoolchildren around the country, providing a suitably entertaining finale to a recording of the rainforest soundscape.

The helmeted hornbill's physical appearance isn't exactly conventional either, with its incongruously long central tail feathers and an impressively large casque – from which this bird derives its name. The latter feature in particular has made this species a prime target for illegal wildlife traders. Typically, hornbill casques are light and hollow, but the helmeted hornbill's appendage is a solid, ivory-like block, making it ideal for carving into ornamental trinkets. Increasing demand for such products, combined with rapid deforestation, poses a grave threat to the survival of the species throughout most of its range.