Writhe-billed Hornbill Rhabdotorrhinus waldeni Scientific name definitions

60–65 cm. Medium-sized black hornbill with broadly black-tipped white tail that becomes stained rufous with preen oil. Male crown and hindneck dark brown, head and neck and upper breast rufous; bill orange-red, base of lower mandible ridged, high wrinkled casque red and orange; bare skin around eye and on throat saffron-yellow; eyes deep red. Female smaller, head to breast black, blue or green tinge to less extensive facial skin, eyes browner. Juvenile similar to adult male, but bill smaller, paler and casqueless, facial skin white or pinkish, eyes pale grey.

C Philippines: Panay and Negros (almost extinct in latter); extinct on Guimaras (1 BirdLife International (2013). IUCN Red List for birds. URL: http://www.birdlife.org (download Aug 2013). Close ).

Inhabits evergreen forest with closed canopy, but will also use selectively logged forest, and even recorded at times at large trees in clearings; occurs from coast up to 950 m on Negros, to 1200 m on Panay. Seems to require larger trees for nesting than does partially sympatric Penelopides panini.

Probably sedentary, except for local movements in search of food.

Mainly fruit, including figs. Usually encountered in only small groups of up to 4 birds, rarely 25–30.

A repeated bisyllabic or trisyllabic nasal bark “wa-hah” or “wa-ha-hah”, reminiscent of the bleating of a lamb (2 Kemp, A.C. (1995). Bird Families of the World. The Hornbills: Bucerotiformes. Oxford University Press, Oxford. Close ).

Probably lays in Mar; chicks collected from nests in May–Jul. Nest in natural cavity in large Shorea polysperma tree, or in old woodpecker hole, 2 nests each 17 m above ground; both sexes seal entrance. Aggressive towards Penelopides panini near nest. Clutch 2 eggs, rarely 3; no other information.

CRITICALLY ENDANGERED. CITES II. Restricted-range species: present in Negros and Panay EBA. Very few documented records since first discovered in 1870s, and hardly any for first 80 years thereafter. Fieldwork on Panay in 1990s found density of 0·2–0·3 nests/km², and maximum of 60–100 pairs estimated. Population in the Central Panay Mountain Range estimated to comprise 502 breeding pairs in 2006, with 1018 active nest holes located in 2008 BirdLife International (2015) Species factsheet: Rhabdotorrhinus waldeni. Downloaded from http://www.birdlife.org on 04/06/2015. . Has been recorded at three sites on Negros, including breeding birds, but population now thought to be functionally extinct; forest habitat virtually eliminated on Guimaras, and species presumed extinct there. Known population therefore fewer than 2500 mature individuals BirdLife International (2015) Species factsheet: Rhabdotorrhinus waldeni. Downloaded from http://www.birdlife.org on 04/06/2015. . Lowland forest on Panay and, especially, on Negros much reduced; some 8% of Panay and 4% of Negros remained forested in 1988, falling twenty years later to 6% and 3% respectively BirdLife International (2015) Species factsheet: Rhabdotorrhinus waldeni. Downloaded from http://www.birdlife.org on 04/06/2015. . Although it seems to prefer hill forest, which has been slightly less affected, species is now very rare and local. Still hunted, and up to 25% of total population of NW Panay shot on a single day in 1997. Up to 50% nests formerly robbed for food and trade, and, especially on Panay, for local exhibition; however, a community nest-guarding scheme has reduced nest poaching by 95% BirdLife International (2015) Species factsheet: Rhabdotorrhinus waldeni. Downloaded from http://www.birdlife.org on 04/06/2015. . Widespread public awareness campaigns are under way. Captive breeding efforts aim to supply a reintroduction programme on Negros. Potential habitat is protected on Negros by Mt Canlaon Natural Park and North Negros Forest Reserve, while the proposed Central Panay Mountains National Park would conserve the species on Panay. It is to be hoped that recent conservation action can reverse the extremely rapid population decline which has pushed this species to the brink of extinction.