Description wikipedia

The Christmas imperial pigeon or Christmas Island imperial pigeon (Ducula whartoni), also known as Black imperial pigeon, Dusky imperial pigeon, Wharton's imperial pigeon, or burong pergam , is a large imperial pigeon endemic to Christmas Island in the northeastern Indian Ocean. It has an overall grey-blue colouration, and juveniles are duller than adults. It makes a soft purring coo sound and a deeper whoo sound comparable to a cow mooing. It lays one glossy white egg per brood, and is possibly somewhat colonial. Other than the Christmas Island flying fox, the Christmas imperial pigeon is the only fruit-eating (frugivorous) animal on the island, and the pigeon feeds and nests in the dense canopy. It mainly inhabits the tropical inland plateau, and widespread non-native Jamaican cherry forests. It was previously thought to be in danger of extinction due to habitat loss and invasive species (specifically the yellow crazy ant), but it is now considered to be rather common, with a breeding population of about 5,000.