Justification of Red List Category
This species has a very large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence <20,000 km² or Area of Occupancy <2,000 km² combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). The population size has not been quantified, but it is not believed to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline, either estimated to be declining by >10% in ten years or three generations, or with a specified population structure). The population trend is not known, but the population is not believed to be decreasing sufficiently rapidly to approach the thresholds under the population trend criterion (>30% decline over ten years or three generations). For these reasons the species is evaluated as Least Concern.
This duck has been described as 'often scarce but locally fairly common' (Coates 1985). It is 'rare to uncommon' in accessible areas where hunting may have reduced the population density, but can be easily found in some areas with moderate disturbance, and there are large areas of inaccessible habitat across its range (J. Bergmark in litt. 2021). It is uncommon below 600 m and is most common at the highest altitudes (Coates 1985, Beehler et al. 1986, Callaghan and Green 1993, J. Hornbuckle in litt 1999, Beehler and Pratt 2016). The population size and subpopulation structure are unknown.
The population trend is unknown.
Salvadorina waigiuensis is endemic to the mountains of New Guinea (Papua, Indonesia and Papua New Guinea). It occurs across the island in suitable montane habitat.
There are records at 70 m in the Lakekamu Basin and it has been recorded from up to 4,300 m (Sam and Koane 2013). It is uncommon below 600 m and is most common at the highest altitudes (Coates 1985, Beehler et al. 1986, Callaghan and Green 1993, J. Hornbuckle in litt 1999, Beehler and Pratt 2016). It breeds beside fast-flowing rivers and streams and alpine lakes, and has also been recorded on slow-flowing rivers (Coates 1985, Callaghan and Green 1993). The species uses small tributary streams as well as main river channels, a factor which may contribute to its perceived rarity. It is not sociable, and one rarely encounters anything beside single adults or pairs (B. Beehler in litt. 2007, Pratt & Beehler 2015). Breeding territories are variable in size owing to local conditions, for instance pairs have been found to occupy 1,600 m of stream on the Baiyer River (Kear 1975) but only 160 m on the Ok Menga River (Bell 1969). It lays clutches of two to four eggs alongside rivers or lakes in the dry season (Kear 1975). It is omnivorous, feeding on aquatic invertebrates, tadpoles and plants by dabbling and diving (Kear 1975, Coates 1985, Pratt & Beehler 2015). The species has been observed using an ephemeral lake at 1,650 m in the Foja Mts of western New Guinea (B. Beehler in litt. 2012), indicating that it can cross expanses of closed forest in search of suitable habitat, and it is likely to disperse between watersheds (G. Dutson in litt. 2012).
Some local extirpations and declines have been attributed to hunting (Bishop 1987, K. D. Bishop in litt. 1994), predation by dogs, and habitat degradation, largely through increasing human pressure and siltation, especially from hydroelectric projects, mining and logging (Murray 1988, A. Mack in litt 1999), but these have only impacted small areas (B. Whitney in litt. 2000). The stocking of alpine rivers with exotic trout species has been suggested as a potential risk to food sources (Kear 1975, Callaghan and Green 1993).
Conservation Actions Underway
This species is protected by law in Papua New Guinea (Callaghan and Green 1993). It is known to be fairly common within the Crater Mountain Wildlife Management Area where it has been a focus of specific study (Straus 2006).
43 cm. Small duck of montane rivers and lakes. Dark brown head. Body barred and spotted dark brown and off-white. Yellow bill. Orange legs. Similar spp. None of the many species of duck recorded in New Guinea have a yellow bill and uniform chocolate head or a barred body. Whistling-ducks, usually found in the lowlands, combine rather plain heads with pale spots or stripes on the flanks and Australian White-eyed Duck Aythya australis has uniformly plain brown plumage. Voice Various calls only given in courtship. Hints Elusive and rather unpredictable at all known sites.
Text account compilers
Beehler, B.M., Bishop, K.D., Hornbuckle, J., Mack, A., Whitney, B., Dutson, G., North, A., O'Brien, A., Derhé, M., Butchart, S., Bird, J., Mahood, S., Pilgrim, J. & Bergmark, J.
BirdLife International (2023) Species factsheet: Salvadorina waigiuensis. Downloaded from http://www.birdlife.org on 21/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 21/03/2023.