Helmeted Hornbill

Beastall, C., Shepherd, C.R., Hadiprakarsa, Y. et Martyr, D. (2016). Trade in the Helmeted Hornbill Rhinoplax vigil: the 'ivory hornbill'. Bird Conservation International, 26(2), 137–146.

Of the 2,170 specimens recorded, 1,117 came from 13 seizures in Indonesia and 1,053 from 18 seizures in China — most of the hunting occurring in Sumatra and Borneo, before shipment to China where casques are carved for the ornamental market. Unlike elephant ivory, the hornbill's casque is a single, non-renewable organ: taking it is necessarily fatal to the bird.

UICN, Liste rouge — Rhinoplax vigil, réévaluation 2015.

A two-category jump in threat status in a single assessment is rare and signals a major revision of perceived risk, not a gradual worsening already underway at the time of earlier assessments — here entirely driven by the sudden surge in casque trafficking documented by Beastall et al. over the same period.

Nakabayashi, M., Inoue, Y., Ahmad, A.H. et Izawa, M. (2019). Limited directed seed dispersal in the canopy as one of the determinants of the low hemi-epiphytic figs' recruitments in Bornean rainforests. PLOS ONE, 14(6), e0217590.

Of 17 identified seed-deposit microsites for the hornbill, 58.8% were on the ground, 29.4% on foliage, and only 11.8% on a branch — the only microsite where seed survival was meaningful. Mean dispersal distance reached 1,612 m, with 53.3% of seeds dispersed beyond one kilometer: the bird disperses far, but rarely to the right spot — an already inefficient function, and so all the more vulnerable to any further drop in bird density.