Animalia > Chordata > Aves > Bucerotiformes > Bucerotidae > Aceros > Aceros waldeni

Aceros waldeni (Walden's Hornbill; Rufous-headed Hornbill)

Wikipedia Abstract

The Walden's hornbill (Aceros waldeni) locally called dulungan, also known as the Visayan wrinkled hornbill, rufous-headed hornbill or writhed-billed hornbill, is a critically endangered species of hornbill living in the rainforests on the islands of Negros and Panay in the Philippines. It is closely related to the writhed hornbill, but can be recognized by the yellow throat and ocular skin in the male, and the blue throat and ocular skin in the female (both throat and ocular skin are deep orange or red in both sexes of the writhed hornbill). Its binomial name commemorates the Scottish ornithologist Viscount Walden.
View Wikipedia Record: Aceros waldeni

Endangered Species

Status: Critically Endangered
View IUCN Record: Aceros waldeni

EDGE Analysis

This colourful and distinctive bird is the World’s second most endangered hornbill. Like most hornbills it possesses a bony ‘casque’, which protrudes from the top of its bill. In the Rufous-headed Hornbill this structure is red-orange and has a wrinkled appearance. Originally found on the three islands of Negros, Panay and Guimaras, it is now locally extinct from the latter due to severe deforestation. Hunting and nest poaching confound this.
Uniqueness Scale: Similiar (0) 
 Unique (100)
Uniqueness & Vulnerability Scale: Similiar & Secure (0) 
 Unique & Vulnerable (100)
ED Score: 11.1527
EDGE Score: 5.27014
View EDGE Record: Aceros waldeni


Adult Weight [1]  2.094 lbs (950 g)
Female Weight [1]  1.653 lbs (750 g)
Male Weight [1]  2.535 lbs (1.15 kg)
Weight Dimorphism [1]  53.3 %
Diet [2]  Frugivore
Diet - Fruit [2]  100 %
Forages - Canopy [2]  90 %
Forages - Ground [2]  10 %
Clutch Size [3]  2


Name Countries Ecozone Biome Species Report Climate Land
Greater Negros-Panay rain forests Philippines Indo-Malayan Tropical and Subtropical Moist Broadleaf Forests

Important Bird Areas

Name Location  IBA Criteria   Website   Climate   Land Use 
Central Panay mountains Philippines A1, A2
Cuernos de Negros Philippines A1
Mount Kanla-on Natural Park Philippines A1, A2
Northwest Panay Peninsula Natural Park Philippines A1, A2
Southwestern Negros Philippines A1, A2

Biodiversity Hotspots

Name Location Endemic Species Website
Philippines Philippines Yes

Prey / Diet

Prey / Diet Overlap


Southern Asia;

External References



Attributes / relations provided by
1Wildlife As Canon Sees It
2Hamish Wilman, Jonathan Belmaker, Jennifer Simpson, Carolina de la Rosa, Marcelo M. Rivadeneira, and Walter Jetz. 2014. EltonTraits 1.0: Species-level foraging attributes of the world's birds and mammals. Ecology 95:2027
3Jetz W, Sekercioglu CH, Böhning-Gaese K (2008) The Worldwide Variation in Avian Clutch Size across Species and Space PLoS Biol 6(12): e303. doi:10.1371/journal.pbio.0060303
4"Fig-eating by vertebrate frugivores: a global review", MIKE SHANAHAN, SAMSON SO, STEPHEN G. COMPTON and RICHARD CORLETT, Biol. Rev. (2001), 76, pp. 529–572
5Interactions among Frugivores and Fleshy Fruit Trees in a Philippine Submontane Rainforest, Andreas Hamann and Eberhard Curio, Conservation Biology Volume 13, No. 4, August 1999, Pages 766–773
Ecoregions provided by World Wide Fund For Nature (WWF). WildFinder: Online database of species distributions, ver. 01.06 WWF WildFINDER
Biodiversity Hotspots provided by Critical Ecosystem Partnership Fund
Abstract provided by DBpedia licensed under a Creative Commons License