Ornithologists have utilized camera traps to document a newly identified species of jewel bubbler in the lush karst forests of Papua New Guinea’s Southern Fold Mountains.
Camera trap images showcasing the holotype and two paratypes of Ptilorrhoa urrissia taken during a detailed 3-month sampling in a high-density array over 0.5 ha. The holotype (ac, marked ‘h’ in image a) and a paratype (a and d, marked ‘p’ in image a), an adult female and juvenile with female-type plumage, were photographed together on January 1, 2020. The shown image is from a sequence of 20 photos captured within 87 seconds. A putative adult male paratype (e) was photographed on March 8, 2020, from under 40 meters. Image credit: Woxvold et al., doi: 10.1111/ibi.70016.
The newly identified species falls under the genus Ptilorrhoa, known for small birds in the family Cinclosomatidae.
Commonly referred to as jewel bubblers, these unique birds are endemic to New Guinea.
According to Ian Wachsvold, an ornithologist with the Australian Museum Research Institute, “Jewel bubblers are a group of ground-dwelling, insectivorous passerines found exclusively in New Guinea and nearby land-bridge islands.”
“These birds are characterized by their plump bodies, short wings, black masks, and white throat or cheek patches, with many species having soft feathers adorned with blue or maroon markings.”
“Typically vocal but shy, they dwell deep within the forests, making them more often heard than seen.”
“Currently, there are four recognized species, with three found across much of New Guinea, differentiated mainly by their altitude – Ptilorrhoa caerulescens lives in lowland areas, while Ptilorrhoa castanonota resides in hills and low mountains; Ptilorrhoa leucosticta prefers dense forests.”
“The fourth species, the brown-headed jewel bubbler (Ptilorrhoa geislerorum), has been recorded in two geographically separated regions: the hills and lowlands of northeastern Papua New Guinea, and a recently discovered population presumed to be this species located far west of Yapen Island.”
In 2017, Dr. Wachsvold and Leo Regula from Lihir Gold Ltd. initiated a biennial camera trap monitoring program for ground-dwelling birds and mammals on the Igif Ridge (Uri [mount] Uricia in the local Fasu language), a limestone forested anticline situated on the southeastern fringe of the Agogo Mountains in the Southern Highlands Province of Papua New Guinea.
Throughout this research, distinctive, undescribed jewel bubblers were captured on camera.
“During over 1,800 camera days, we recorded 10 images of the bird across three sequences (trigger events) using two cameras set approximately 600 meters apart,” the researchers noted.
“In November 2018, we attempted to set up mist nets to capture these birds but were unsuccessful.”
“Camera trap surveillance was repeated in 2019, 2021, and 2024, accumulating a total of 94 photographs (22 sequences) and seven 30-second videos (4 sequences) featuring at least three to six birds, with 11 cameras monitoring an area of 16 hectares.”
Analysis of museum specimens alongside field photographic evidence confirms that the bird in question distinctly differs from other known Ptilorrhoa species.
Pyroroa urrissia),” they stated.
Pyroroa urrissia appears to be a resident species in the Yagif Ridge area, with birds photographed consistently over a span of ten consecutive months (June through March) across seven years.
The total number of newly detected species during the sampling period probably comprises fewer than ten birds.
“This species tends to be observed alone, in pairs, or in small family groups of three to four,” the researchers highlighted.
“Data indicates a similar social organization to other jewel bubblers worldwide. The Pyroroa urrissia duo is frequently photographed together, with most records (all but 3 sequences of one male) gathered from a 7 ha area; most likely indicating two breeding events involving a resident pair and their offspring.”
“We hypothesize that the Igif Ridge supports a fragmented population occupying an isolated low mountain lacking higher altitude support for Ptilorrhoa leucosticta,” they add.
“Potentially suitable habitats may be restricted to regions between Mt Bosabi and Mt Karimui in southern Papua New Guinea.”
To date, no songs have been distinctly attributed to any Ptilorrhoa species aside from Ptilorrhoa castanonota, although the team did encounter vocalizations on the Igif Ridge.
The new species appears to produce softer calls compared to other species such as Ptilorrhoa caerulescens and Ptilorrhoa castanonota, while showing behavioral similarities to Ptilorrhoa leucosticta.
“Jewel bubblers on the Igif Ridge are threatened by multiple factors,” scientists warn.
“Known native predators include at least three marsupials, such as the New Guinea quoll (Dasyrus albopuntatus), the woolly three-striped dasher (Myoichthys leucula), and certain Murexia species. Furthermore, the Papuan eagle (Harpyopsis novaeguineae), goshawk (Accipiter poliocephalus), and the great owl (Tito tenebricosa) prey on the ground, possibly targeting adult birds or their young.”
“Invasive predators represent an additional significant risk, especially for ground-nesting species like the jewel bubbler.”
“Domestic cats (Felis catus) have been photographed on Igif Ridge thrice in 2021 and 2024.”
“Dogs (Canis lupus familiaris) are frequently spotted in the area, often accompanying hunters or loitering opportunistically.”
“Lastly, climate change poses a severe threat to tropical montane birds, particularly those like Pyroroa urrissia that have limited dispersal capabilities and no access to high-altitude environments on Igif Ridge.”
The findings of this significant discovery were published in a study in the journal Toki on November 26, 2025.
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Ian A. Wachsvold et al. A newly identified species of jewel bubbler (Cinclosomatidae: Ptilorrhoa) from Papua New Guinea’s Southern Fold Mountains. Toki, published online November 26, 2025. doi: 10.1111/ibi.70016
Source: www.sci.news
