Scaly-breasted Kingfisher Actenoides princeps


Justification of Red List category
This species has an extremely large range, and hence does not approach the thresholds for Vulnerable under the range size criterion (extent of occurrence <20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appears to be decreasing, the decline is not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size has not been quantified, although is considered unlikely to approach the thresholds for Vulnerable under the population size criterion (<10,000 mature individuals with a continuing decline estimated to be >10% in ten years or three generations, or with a specified population structure). For these reasons the species is evaluated as Least Concern.

Population justification
The population size has not been specifically estimated, but the species is reported to be uncommon (del Hoyo et al. 2001, Eaton et al. 2021). Although eBird (2023) data suggest that it is sparsely distributed, much of its range is totally inaccessible. Moreover, Actenoides kingfishers are elusive with low detectability (Fry and Fry 1999). Within its large range remains 30,000 km2 of forest, such that even if it does prove to occur at an unusually low density/occupancy, the population size is very likely to be above 10,000 mature individuals.

Trend justification
The population was previously suspected of undergoing sustained population losses because of habitat loss. However, recent remote sensing data (Global Forest Watch 2023, based on data and methods from Hansen et al. [2013]) suggest that in the three generations (12 years) to 2023, this amounted to no more than 2% loss of forest cover extent. Future projections (Voigt et al. 2021) also show the majority of this species' range remaining intact up to 2050. Consequently, although the species is considered highly forest dependent, it is thought to be declining only slowly in response to localised forest loss and degradation, particularly at the lowest elevations of its range. Rates of population reduction are therefore not likely to have exceeded 5% over three generations and, even if rates accelerate (Voigt et al. 2021), are unlikely to exceed 9% in the next three generations.

Distribution and population

The species is endemic to Sulawesi, Indonesia. A. p. princeps occurs in north-east Sulawesi and A. p. regalis in south-east Sulawesi, while A. p. erythrorhamphus is more widespread in central, north-west and south-west Sulawesi (White and Bruce 1986, Fry and Fry 1999, del Hoyo et al. 2001). A sighting of an Actenoides kingfisher at Gunung Tumpu, in East Sulawesi (Rheindt et al. 2014) may be attributable to an undescribed taxon (or species). Notably, taxon regalis (sometimes afforded species rank: e.g., in del Hoyo et al. 2014) has not been seen since the collection of the two known specimens (a female and immature male) in December 1931, despite some moderate search effort (White and Bruce 1986, Berryman and Eaton 2020, eBird 2023, Rutt et al. in prep.).


This is an inconspicuous species of Sulawesi's montane and submontane forests, where it perches unobtrusively in the forest understorey (Fry and Fry 1999). It principally occurs at 900-2,000 m (Eaton et al. 2021), but was recorded as low as 250 m (White and Bruce 1986).


The only identified threat to this species is forest loss, which is suspected to be causing slow declines in this highly forest-dependent species. In the three generations (12 years) to 2023, this was low (c. 2%) but may increase in the future as forests become more accessible to logging (Voigt et al. 2021). The primary cause of forest loss localised agricultural shifts/small-holder farming, and some plantations.

Conservation actions

Conservation and research actions underway
No specific action is known, although this species benefits from and occurs in numerous protected areas including Dumoga-Bone and Lore Lindu National Parks, and Gunung Ambang and Tangkoko Duasudara Nature Reserves.

Conservation and research actions proposed
Investigate the taxonomy of this complex to see if more than one species is involved. Undertake searches for A. p. regalis (Berryman and Eaton 2020) and the undescribed taxon from Gunung Tumpu (Rheindt et al. 2014) to clarify their status, distribution and taxonomy. Conduct repeated surveys of known and potential sites across Sulawesi in order to determine abundance and population trends. Conduct ecological studies to determine levels of tolerance of secondary habitats, particularly in areas where primary forests have been extirpated. Ensure the protection of existing forest reserves.


24-25 cm. A medium-sized forest kingfisher with a dark blue head, brownish upperparts heavily scalloped with buff and finely barred pale underparts. The female has buff supercilium and moustachial stripes. 


Text account compilers
Berryman, A.

Recommended citation
BirdLife International (2024) Species factsheet: Actenoides princeps. Downloaded from on 03/03/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from on 03/03/2024.