Justification of Red List Category
This species is listed as Vulnerable because it has a small population that is inferred to be in slow decline owing to habitat loss from forest clearance for subsistence gardens and hunting of adult males for their plumes.
Male home ranges have been estimated at 5-100 ha (Pruett-Jones and Pruett-Jones 1988, Whiteside 1998). The EOO is 22,000 km2, but this species is notably patchy. If it inhabitants 5% of its EOO, the population would be in the order of 1,000-20,000 males. Here the overall population is precautionarily estimated to number 2,500-9,999 mature individuals. The subpopulation structure is not known but it is plausible that no subpopulation is >1,000 mature individuals.
There are no quantitative data available to calculate population trends; however, the species is suspected to be declining slowly, owing to pressure from forest clearance for subsistence gardens. It might also be declining from hunting for its plumes. There is also a slow rate of forest loss and degradation from logging and infrastructure development.
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 patchily distributed and absent in many areas, including in seemingly suitable habitat in eastern Papua New Guinea, and is nowhere common (Frith and Beehler 1998, K. D. Bishop in litt. 2000, B. Beehler in litt. 2012, Beehler and Pratt 2016). Advertising males were spaced at about every 200 m along one suitable forest ridge, and 400 m along another, and three radio-tagged birds had home ranges of 5, 17 and 33 ha over c.50 days (Pruett-Jones and Pruett-Jones 1988). At another study site, males were less dense, occupying up to 100 ha, perhaps owing to the more patchy forest or the higher hunting pressure at this site (Whiteside 1998). The species can also be found in degraded forest remnants, at the edges of gardens and in copses of planted trees in upland valleys of central Papua New Guinea. Singing adult males have been reported in the highly populous Tari Valley, including in village woodlots and in areas with little original forest, suggesting a tolerance of highly degraded forest (B. Beehler in litt. 2012, Beehler and Pratt 2016). Locals also collected a nestling here, indicating these birds can reproduce in these degraded forests (van den Bergh et al. 2013, M. van den Bergh in litt. 2016).
It occurs in lower montane forest, mainly at 1,400-1,800 m, but occasionally from 1,100 to 2,000 m , especially female-plumaged birds. Although displaying males usually use patches of primary forest, they have also been reported singing in the highly populous Tari valley, in areas with little remaining primary forest (B. Beehler in litt. 2012). The species is able to tolerate highly degraded habitats, 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). However, it may be excluded from more degraded habitats as a result of hunting of males and competition with the more adaptable Raggiana Bird-of-paradise P. raggiana. The discovery of a nestling in degraded habitat suggests breeding in these areas may be possible (van den Bergh et al. 2013), but young birds may be more vulnerable to collecting in these inhabited areas (van den Bergh in litt. 2016). The favoured elevational zone continues to be degraded by intensified agriculture from a growing rural population. It is largely a canopy species feeding mainly on fruit and arthropods extracted from epiphytes and bark on branches (Coates 1990, Mack 1992, Frith and Beehler 1998, Pratt & Beehler 2015). Nests are flat cups placed on the fork of low lying branches (Pratt & Beehler 2015).
Forest in the species’s favoured elevational zone is under pressure from clearance for subsistence gardens by the increasing human population. However, agriculture-related habitat alteration does not necessarily preclude the species from these areas as it has been found to occur in mosaics of highly degraded forest remnants and gardens, and can survive in human-dominated ecosystems (B. Beehler in litt. 2012, G. Dutson in litt. 2012). The second major threat is hunting of adult males for their pectoral and tail feathers (Beehler 1985, Coates 1990, Frith and Beehler 1998). Although hunting occurs mainly for collection of feathers for traditional customary practices, birds or feathers are occasionally sold to tourists (van den Bergh 2009), even though it is illegal to take them out of the country. Group interviews suggest hunting pressure for these customary practises are increasing in several Tari clans. This might be partly explained by new celebratory events for which the feathers are collected, for example Independence Day (van den Bergh et al. 2013) and Christmas, although Christian priests forbid the hunting of birds of paradise (M. van den Bergh in litt. 2014). Despite a law designed to prevent the killing of birds with non-traditional means (i.e. shotguns), there are many more children than 40 years ago, who shoot fairly significant numbers of birds on the nest, using slingshots (B. Beehler in litt. 2012). Research has also revealed that these laws and regulations are often not enforced, or routinely misunderstood, meaning that they have had little influence on hunting pressure and trade (M. van den Bergh in litt. 2014). Although the species is hunted for its plumes, it is not worn as commonly as other species in the Tari research area and is not frequently sold (particularly in the highlands). People in the Enga clan however hold specific importance to feathers of this particular species, and do not substitute for other species (van den Bergh et al. 2013). Several tribal groups still use the species’s plumes and so hunting is likely to be concentrated in certain areas (B. Beehler in litt. 2012, M. Supuma in litt. 2012). There are still significant areas of its range which are inaccessible and largely uninhabited (Coates 1990, Frith and Beehler 1998, B. Beehler in litt. 2012).
Conservation Actions Underway
CITES Appendix II. This species is protected by law in Papua New Guinea (Fauna Act of 1966-73), although this is routinely not enforced (M. van den Bergh in litt. 2014). It is officially illegal for non-citizens to take birds-of-paradise without a permit from the Department of Environment & Conservation and to kill birds of paradise with anything other than traditional means (Beehler in litt. in van den Bergh 2009, Sekhran & Miller 1996). While all birds of paradise are protected by the Papua New Guinea Fauna Act (1968), the enforcement of this protection is challenging, considering that over 93% of land ownership rests with traditional custodians (M. Supuma in litt. 2012). In addition, there is a distinct lack of funds to support enforcement officers to monitor the trade of the species.
30 cm. Dark bird-of-paradise with stout, ivory bill, broken white eye-ring and blue wings, back and tail. Male is otherwise black with fine, blue tail plumes and two long streamers. Female has chestnut underparts. Similar spp. Both the head pattern and the blue upperparts are unique. Other congeners are larger, slimmer and longer-tailed. Voice Displaying males give a slowly cadenced series of notes wahr..wahr.. and a metallic humming when inverted, also croaking and growling contact calls. Hints Can be seen in fruiting trees but to see males in their famous inverted display, seek local guides.
Text account compilers
Derhé, M., Dutson, G., Mahood, S., O'Brien, A., Stattersfield, A., Symes, A., Taylor, J. & North, A.
Beehler, B., Bishop, K., Dutson, G., Leary, T., Supuma, M. & van den Bergh, M.
BirdLife International (2021) Species factsheet: Paradisornis rudolphi. Downloaded from http://www.birdlife.org on 25/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 25/10/2021.