Feeding Ecology of Plain-pouched and Oriental Pied Hornbills in Mixed Deciduous Forest, Northwestern Thailand Feeding Ecology of Plain-pouched and Oriental Pied Hornbills in Mixed Deciduous Forest, Northwestern Thailand
The aim of this study is to research the feeding ecology of Plain-pouched Hornbill Rhyticeros subruficollis (PPH) in the seasonally flooded mixed deciduous forests of Huai Kha Khaeng Wildlife Sanctuary, Thailand (HKK) in comparison to the Oriental Pied Hornbill Anthracoceros albirostris (OPH) which is a possible competitor of PPH during the breeding season. Nest trees found by the Thailand Hornbill Project in the past were checked and repaired in December 2016 prior to the start of the breeding season. Four out of seven repaired nests were found active (two nests of PPH and two nests of OPH) in February 2017. Each of these nests was then observed from the observation blinds between 7.00 a.m.-5.00 p.m. for 3-7 days. The results show that incubation and nestling phase of PPH were 27 and 70.5 ± 0.7 days, respectively, with 1 chick/nest (n=2). For OPH, these two phases were 15 and 68 days, respectively, with 2 chicks/nest (n=2). Both hornbill species consumed more fruit than animals. PPH consumed more non-figs than figs while OPH comparatively consumed more figs than non-figs. The diet of both species contained a high proportion of fruit and syconium fruit. Cicada was ranked highest in the animal diets of both species. Food preference was similar for both species but the Food Overlap Index was low, indicating low competition between PPH and OPH.