Data Zone
Justification of Red List category
This species has a small population that is suspected to be in slow decline owing to habitat loss from forest clearance and hunting of adult males for their plumes. Its population is likely to be composed of small subpopulations. It is therefore listed as Near Threatened.
Population justification
It is uncommon to rather rare (Gregory 2020). It is patchily distributed and absent in many areas, including in seemingly suitable habitat in eastern Papua New Guinea (Frith and Beehler 1998, K. D. Bishop in litt. 2000, B. Beehler in litt. 2012, Beehler and Pratt 2016), but may be more common in the western part of its range (B. Beehler in litt. 2012, A. Mack in litt. 2012).
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). In Karimui, Chimbu Province, this species appears to be rare. Surveys in the 1960s recorded the species (Diamond, 1972), but surveys in 2012 (Freeman and Class Freeman 2014) did not, and in 2015 one individual was recorded during point counts, leading to a density estimate of one lek per 5 km2 (Supuma 2018). Point count surveys in Hogave (Lufa District) in 2015 recorded two display leks within a 4 km2 area, at a density of two per ten hectares (Supuma 2018).
The species's mapped range contains approximately 44,300 km2 of tree cover with at least 50% canopy cover (Global Forest Watch 2021), but this species is notably patchy. If it inhabits 5% of its mapped range, then based on an estimated male home range of 0.2 - 5 km2, the population would be in the order of 1,900-9,900 males (or 3,800-20,000 mature individuals).
The species has two subspecies (Frith et al. 2020), hence it has at least two subpopulations, and due to its patchy distribution throughout its range, it may well have more than two. It is therefore plausible that no subpopulation is >1,000 mature individuals.
Trend justification
The species has been rare for over a century (Horsbrugh 1909). In the Tari valley of Hela Province, the species was more easily encountered in 2012 than 20 years previously, probably due to the cessation of shotgun hunting (B. Beehler in litt. 2012). In 2008, interviews with local people in the Tari area suggested that the species's population was declining, whilst interviews with local people in the Enga area suggested that the species's population was stable or increasing (van den Bergh et al. 2013).
Overall, the species is suspected to be declining slowly, owing to pressure from forest clearance, and possibly also due to hunting for its plumes. According to Global Forest Watch (2021), approximately 3% of tree cover with at least 50% canopy cover was lost from the species's range over the last three generations. However, this species is able to tolerate degraded habitat and has been observed inhabiting garden edges (M. Supuma pers. com. 2020). While this species is hunted for its plumes, it is not worn or sold as frequently as other species, and hunting is likely to be concentrated in certain areas (B. Beehler in litt. 2012, M. Supuma in litt. 2012). Significant areas of its range are still inaccessible and largely uninhabited (B. Beehler in litt. 2012). Therefore, while the rate of decline is uncertain, it is not currently thought to exceed 20% over three generations. Based on current threats, any declines are likely to continue into the future.
Paradisornis rudolphi occurs in the eastern Central Ranges of Papua New Guinea. The nominate subspecies occurs from the Own Stanley Range, west to the Herzog mountains and Okapa in the Eastern Highlands. Subspecies P. r. margaritae occurs in the Tari valley, Enga Highlands, Sepik–Wahgi Divide, Kubor Range, Mount Giluwe, Mountt Hagen, Mount Karimui and the Bismarck Range (Frith et al. 2020).
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, including in village woodlots and 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, M. Supuma, 2020, pers. comm.), forest edge and nearby disturbed areas (van den Bergh 2009). However, it may be excluded from more degraded habitats in some areas as a result of hunting of males and competition with the more adaptable Raggiana Bird-of-paradise Paradisaea 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 areas (van den Bergh in litt. 2016). 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 mining, logging, and clearance for subsistence gardens and cash-crop (e.g. coffee) agriculture 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, mainly for traditional customary practices, although birds are also eaten locally (Beehler 1985, Coates 1990, Frith and Beehler 1998). It is not worn as commonly as other species in the Tari research area and is not frequently sold (particularly in the highlands; M. Supuma in litt. 2012). 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). Group interviews suggest hunting pressure for these customary practices are increasing in several Tari clans (M. van den Bergh in litt. 2016). 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). At Karimui, hunting activities have increased around villages (Supuma 2018). Despite a law designed to prevent the killing of birds with non-traditional means (i.e. shotguns), there are many more children than there were several decades ago, who shoot fairly significant numbers of birds on the nest, using slingshots (B. Beehler in litt. 2012, Freeman and Class Freeman 2014). 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). Birds or feathers are occasionally sold to tourists (van den Bergh 2009), even though it is illegal to take them out of the country. Evidence has emerged that individuals of this species that are exported under the label of being bred in captivity may actually be wild-caught birds (Shepherd et al. 2012). Historically, the species was traded internationally in large numbers for use of its feathers in the millinery industry, but this was stopped in the 1920s.
Climate change may also affect the species by reducing the amount of habitat available (Supuma 2018).
Conservation Actions Underway
CITES Appendix II. This species is protected by law in Papua New Guinea (Fauna Act of 1966-73), although this is not routinely 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 Conservation and Environment Protection Agency 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
Wheatley, H., Clark, J.
Contributors
Beehler, B.M., Bishop, K.D., Derhé, M., Dutson, G., Leary, T., Mahood, S., North, A., O'Brien, A., Stattersfield, A., Supuma, M., Symes, A., Taylor, J., van den Bergh, M. & Bergmark, J.
Recommended citation
BirdLife International (2024) Species factsheet: Blue Bird-of-paradise Paradisornis rudolphi. Downloaded from
https://datazone.birdlife.org/species/factsheet/blue-bird-of-paradise-paradisornis-rudolphi on 22/11/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from
https://datazone.birdlife.org/species/search on 22/11/2024.