Using camera traps, ornithologists have photographed a previously unknown species of jewel-babbler in the forested karst of the Southern Fold Mountains in Papua New Guinea.
Camera trap images of the holotype and two paratypes of Ptilorrhoa urrissia, taken during a 3-month sampling period in a high-density array covering 0.5 ha: the holotype (a-c, marked ‘h’ in a) and one paratype (a and d, marked ‘p’ in a), putative adult female and juvenile with female-type plumage, respectively, were photographed together on January 1, 2020; the images shown are part of a sequence of 20 photographs taken over a period of 87 s; the putative adult male paratype (e) was photographed less than 40 m away on March 8, 2020. Image credit: Woxvold et al., doi: 10.1111/ibi.70016.
The newly-identified species belongs to Ptilorrhoa, a small bird genus within the family Cinclosomatidae.
Commonly known as jewel-babblers, these birds are endemic to New Guinea.
“The jewel-babblers are a group of ground-dwelling, insectivorous passerines endemic to New Guinea and a few satellite land-bridge islands,” said Australian Museum Research Institute ornithologist Iain Woxvold and colleagues.
“Plump and short-winged, they have a black mask, white throat or cheek patch and soft plumage that in most species is patterned in blue and/or chestnut.”
“They are vocal but shy birds of the forest interior, more often heard than seen.”
“Four species are currently recognized, three of which occupy most of New Guinea but segregate by altitude: the blue jewel-babbler (Ptilorrhoa caerulescens) in the lowlands, the chestnut-backed jewel-babbler (Ptilorrhoa castanonota) in the hills and lower mountains, and the spotted jewel-babbler (Ptilorrhoa leucosticta) in montane forest.”
“The fourth species, the brown-headed jewel-babbler (Ptilorrhoa geislerorum), occurs in two widely separated areas — in the hills and lowlands of northeast Papua New Guinea and a recently discovered population (presumed to be this species) far to the west on Yapen Island.”
In 2017, Dr. Woxvold and his colleague, Leo Legra of Lihir Gold Limited, established a biennial camera trap monitoring study of ground-dwelling birds and mammals on Iagifu Ridge (uri [mount] urrissia in the local Fasu language), a forested limestone anticline located at the southeastern end of the Agogo Range in Southern Highlands Province, Papua New Guinea.
In their image collection, they observed a distinctive, undescribed form of jewel-babbler.
“Over a period of more than 1,800 camera days, 10 images of the bird were obtained in three sequences (trigger ‘events’) taken on two cameras that were separated by c. 600 m and an unsealed access road,” they said.
“In November 2018, we spent 8 days mist-netting and searching for the bird without reward.”
“Camera trap monitoring was repeated in 2019, 2021 and 2024.”
“Overall, 94 photographs (22 sequences) and seven 30-s videos (four sequences) involving at least three to six birds were taken on 11 cameras covering an area of 16 ha.”
The examination of museum specimens and field photographic material confirmed that the birds the authors photographed are distinct from all other known Ptilorrhoa forms.
“Based on these findings, we propose that the birds photographed on Iagifu Ridge represent a new species, which we name: the hooded jewel-babbler (Ptilorrhoa urrissia),” they said.
Ptilorrhoa urrissia appears to be permanently resident on Iagifu Ridge, birds having been photographed in each of 10 consecutive months (June-March) over a period of 7 years.
The total number of the new species detected over the period of sampling is probably fewer than 10 birds.
“Jewel-babblers are normally observed as single birds, pairs or in small family parties of three or four,” the researchers said.
“Available data indicate a similar pattern of social organization in Ptilorrhoa urrissia: duos were regularly photographed together and most records (all but three sequences of a single male) were collected from a 7-ha area and potentially involve a sedentary pair plus one offspring in each of two breeding events.”
“We speculate that Iagifu Ridge may support part of a highly fragmented population that occupies isolated low mountains that do not support Ptilorrhoa leucosticta of higher elevations,” they added.
“Potentially suitable sites may be restricted to the area between Mt Bosavi and Mt Karimui in southern Papua New Guinea.”
No song clearly attributable to any Ptilorrhoa other than Ptilorrhoa castanonota has been heard on Iagifu Ridge by the team.
The new species appears to be less vocal than Ptilorrhoa caerulescens and Ptilorrhoa castanonota and behaviorally closer to Ptilorrhoa leucosticta in this respect.
“Jewel-babblers on Iagifu Ridge face a variety of threats,” the scientists said.
“Native predators confirmed present include at least three marsupials — the New Guinea quoll (Dasyurus albopunctatus), the Woolley’s three-striped dasyure (Myoictis leucura) and one or more Murexia species — plus several avian predators including the Papuan eagle (Harpyopsis novaeguineae), the gray-headed goshawk (Tachyspiza poliocephala) and the greater sooty owl (Tyto tenebricosa), each of which takes prey from the ground and may consume adult birds or their young.”
“Alien predators pose an additional and potentially serious threat, particularly to ground-nesting species such as jewel-babblers.”
“Domestic cats (Felis catus) were camera trapped on Iagifu Ridge on three occasions in 2021 and 2024.”
“Dogs (Canis familiaris) are also regularly detected at the site, either in the company of hunters or as free-roaming individuals and small packs.”
“Finally, climate change poses a serious threat to tropical montane birds, particularly those with low dispersal ability that lack access to higher elevations such as Ptilorrhoa urrissia at Iagifu Ridge.”
A paper about the discovery was published on November 26, 2025 in the journal Ibis.
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Iain A. Woxvold et al. A new species of jewel-babbler (Cinclosomatidae: Ptilorrhoa) from the Southern Fold Mountains of Papua New Guinea. Ibis, published online November 26, 2025; doi: 10.1111/ibi.70016