[4] EBird describes it as "A fairly large bird of lowland and foothill forest on Luzon and neighboring islands.

"[5] The Luzon hornbill was described by the French polymath Georges-Louis Leclerc, Comte de Buffon in 1780 in his Histoire Naturelle des Oiseaux.

[6] The bird was also illustrated in a hand-coloured plate engraved by François-Nicolas Martinet in the Planches Enluminées D'Histoire Naturelle which was produced under the supervision of Edme-Louis Daubenton to accompany Buffon's text.

[7] Neither the plate caption nor Buffon's description included a scientific name but in 1783 the Dutch naturalist Pieter Boddaert coined the binomial name Buceros manillae in his catalogue of the Planches Enluminées.

In a study on a nest in Zambales, a male hornbill fed 32 different species of fruits and berries.

All hornbills are monogamous and mate for life.They are cavity nesters and rely on large dipterocarp trees for breeding.

The female seals itself within the tree cavity, 10 to 30 meters from the ground and the male is in charge of gathering food for its mate and chicks.

The male stores food in a gular pouch and regurgitates it to feed its mate and chicks.

Its threats are mainly habitat loss due to deforestation for lumber, mining and farmlands.