This discussion was first published as part of the 2013 Red List update, but remains open for comment to enable reassessment in 2014.
Blue Bird-of-paradise Paradisaea rudolphi occurs in the eastern Central Ranges of Papua New Guinea, from Mt Sisa south of Tari to the Owen Stanley range. It is currently listed as Vulnerable under criteria C2a(i) of the IUCN Red List, based on a small, patchily distributed population that was suspected to be declining owing to pressure from hunting for its plumes.
The population has been estimated to number 2,500-9,999 mature individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size, and the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied. This estimate is equivalent to 3,750-14,999 individuals, rounded to 3,500-15,000 individuals.
However, the species is tolerant of degraded habitats in human-dominated ecosystems, occurring in garden mosaics, copses of planted trees in upland valleys (B. Beehler in litt. 2012, G. Dutson in litt. 2012), forest edge and nearby disturbed areas (van den Bergh 2009). In addition, hunting levels may be lower than previously thought due to a law preventing the killing of birds with non-traditional means (i.e. shotguns), or it could be that it has become increasingly more difficult to find the species, perhaps due to its patchy distribution (M. Supuma in litt. 2012). The issue that remains is that the species seems to be patchily distributed in eastern Papua New Guinea and still absent from some apparently suitable environments (B. Beehler in litt. 2012). Nevertheless, if this species is found to have a stable population it could qualify for downlisting to Near Threatened under criterion C2a(i).
Further information is required on the estimated population size, distribution, likely population trends, size of the largest subpopulation and on the severity of hunting for this species.
van den Bergh, M. O. L. (2009) Destructive attraction: Blue Birds of Paradise and local inhabitants: an equilibrium?