Habitat preference and population density of threatened Visayan hornbills Penelopides panini and Rhabdotorrhinus waldeni in the Philippines

Abstract

The habitat preference and population density of the Critically Endangered Rufous-headed Hornbill Rhabdotorrhinus waldeni and Endangered Visayan Tarictic Hornbill Penelopides panini were studied in the Central Panay Mountain range in Panay Island, western Visayas. Point counts were established to survey for hornbills and habitat variables were measured in a 30 x 30 m plot at each point. P. panini was recorded in primary and secondary forest, while records of R. waldeni were mostly in primary forest, with only one record in secondary forest. Spearman’s rank order correlation and stepwise multiple regression showed that R. waldeni is positively correlated to density of large trees (>70cm DBH), with the Visayan Tarictic Hornbill showing moderate correlation with density of medium-sized trees (31–70 cm DBH). Central Panay Mountains is the largest remaining forests block in western Visayas. It is the stronghold area of R. waldeni and other western Visayas threatened species, supporting the need to declare the site a protected area.