The blue bird-of-paradise (Paradisaea rudolphi) is a medium-sized bird-of-paradise.
Regarded by some ornithologists as the loveliest of all birds, the blue bird-of-paradise was discovered by Carl Hunstein in 1884. The scientific name commemorates the ill-fated Crown Prince Rudolf of Austria.
Due to ongoing habitat loss, limited range, small population size and, in some areas, by hunting for its highly prized plumes, the rare blue bird-of-paradise is classified as Vulnerable on the IUCN Red List of Threatened Species. It is listed on Appendix II of CITES.
The blue bird-of-paradise is endemic to Papua New Guinea. It is distributed to mountain forests of southeastern New Guinea. ITIS recognizes only one subspecies, but additional subspecies P. r. margaritae and P. r. ampla have been described. Handbook of the Birds of the World recognizes the former margaritae of East Central New Guinea and nominate rudolphi of South-east New Guinea. source