The Collared Imperial Pigeon, Ducula mullerii, is a robust bird with an average length of 40 cm and a weight around 600 grams. Its plumage is primarily grey with grey-pink hues on the underparts. A distinctive feature of this species is the complete black collar that stands out against the white throat, a characteristic that is both striking and diagnostic.
When identifying the Collared Imperial Pigeon, look for its large size and the unique black collar that contrasts sharply with the white throat. The grey upperparts and grey-pink underparts are also key features to note. The bird's overall robust structure and coloration make it quite distinguishable from other pigeon species.
This pigeon favors the lushness of lowland rainforests, swamp forests, and mangroves. It is also found in riverine vegetation, where it can be seen perching or foraging.
Native to New Guinea and the adjacent Aru Islands, the Collared Imperial Pigeon is also present on Boigu and Saibai islands. Occasionally, it may appear as a vagrant on the northern Torres Strait islands.
The diet of the Collared Imperial Pigeon is predominantly frugivorous, consisting mainly of fruit from forest trees. It has a particular fondness for the fruit of Tristiropsis canarioides and ylang-ylang (Cananga odorata), as well as various fruits from Arecaceae (palm) species. Remarkably, this pigeon is capable of swallowing fruits whole, even those up to 5 cm in diameter.
Breeding behavior includes the construction of a rather flimsy platform nest within forest trees adjacent to wetlands. The pigeon lays a single egg, which then becomes the focus of its parental care.
The Collared Imperial Pigeon is currently classified as Least Concern on the IUCN Red List. This status indicates that, at present, the species does not face an immediate threat of significant population decline.