Study of the oriental pied hornbill egg incubation and chick behaviour, during incubation and chick-rearing phases of breeding in captivity and in the wild.

Abstract

The female Oriental Pied Hornbill (OPH) seals herself inside the nest cavity throughout the nesting cycle, laying up to four eggs per cycle. During this period, she is entirely reliant on the male, who is the sole provider of food for her and the chick(s). Infanticide-cannibalism, where the mother kills and consumes weaker chick(s) has been known to occur during the chick-rearing phase. The OPHs behaviour is crucial in determining the success of egg-hatching and chick survival, both in captivity and in the wild. Direct observation of female and chick behaviour inside the nests was conducted through 24-hour camera surveillance. The internal nest environment was monitored using temperature, humidity, and CO2 and O2 sensors. This year two pairs of OPH, one at Jurong Bird Park and another at Pulau Ubin were studied. Egg-hatching success was found to be better in the wild (75.0%) than in captivity (33.3%). The chick(s) sensitivity to temperature fluctuations was evident, when it/they hid under the mother more often on days when temperatures were lower. In the wild, chick(s) situated nearer the nest entrance during male visits, and chick(s) born even a day earlier, was/were observed to have an advantage when begging for food and succeeding in getting fed.