Data Zone
Justification of Red List category
This species has a pan-Sundaic distribution, occurring on the Thai-Malay Peninsula, Sumatra and Borneo. Here, lowland forest losses have been among the most rapid in the world (principally to make way for oil palm plantations), and this highly forest-dependent species is suspected of having declined rapidly in response. Over the last three generations (12 years: 2010-2022) it is suspected of having declined by more than 30%, and unless rates of deforestation slow rapidly, it will soon be confined to a fragmented network of protected areas. Accordingly, it is listed as Vulnerable.
Population justification
The global population size has not been quantified but is believed to be large given the range and frequency of records in suitable habitat. It is a highly forest-dependent species that has been recorded only from undisturbed forest (Simamora et al. 2021, eBird 2022). Within its range, the rate of forest conversion to plantations, primarily oil palm, has been very rapid over the past few decades (per Global Forest Watch 2022). There are recent records from remaining forested areas across much of the range, however the extent of suitable habitat is now considerably smaller than three generations ago. Where habitat is secure the species continues to be regularly observed (eBird 2022), though observing the species away from protected areas is becoming increasingly difficult. In Thailand, there are very few recent records and the population there must now be very small. Almost all records in Malaysia now come from protected areas or forest concessions, and the population is thought to be declining rapidly in lowland Indonesia, although here (especially in Kalimantan), there are large tracts of suitable habitat remaining. Forest loss is much lower in Brunei, where impacts on the species may be much less severe and much of the forest here is likely to be suitable for this species. Overall, the population is considered highly unlikely to meet or approach he threshold for listing as threatened (<10,000 mature individuals) although this requires confirmation.
Trend justification
Harpactes orrhophaeus is thought to be declining rapidly in response to extensive forest cover loss across its range. Determining the rate of population decline for this species is difficult owing to differences in elevational preferences across its range. Nonetheless, it is consistently considered the scarcest of the South-East Asian Harpactes and appears to be the most threatened. On the Thai-Malay Peninsula, it occurs only to c.200 m (Wells 1999, Treesucon and Limparungpatthanakij 2018) where forest cover loss has been extremely rapid. This is coupled with an apparently sizeable range contraction with no evidenced Thai records for several years (eBird 2022), despite its historical occurrence up to the Isthmus of Kra (e.g. Round et al. 1982). Similarly, there are no recent records from north-east Peninsular Malaysia (Kelantan, Terengganu) or Perak, despite the species formerly occurring there (MNS Bird Conservation Council 2021). On Sumatra the species occurs up to 600 m (Eaton et al. 2021) but most habitat at or below this elevation has been cleared; there are recent records from only a handful of widely scattered localities (eBird 2022). On Borneo, which now must reasonably be considered the species' stronghold outside some protected areas in Peninsular Malaysia, it is documented as preferring submontane forest, and the species has been observed as high as 1,500 m in Sarawak (Mann 2008). However, the majority of records and documented localities are from the lowlands below 600 m (Mann 2008, eBird 2022) where forest cover loss has been rapid since 2000 (Global Forest Watch 2022). Combining these preferences with the relative total area (used as a proxy for likely population size in each area), in the three generations (12 years; Bird et al. 2020) to 2021, the area of forest cover in this species' range was reduced by 21-26%, depending on the assumptions used (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). Moreover, this species is likely to be impacted by habitat degradation. Neither Husin and Rajpar (2015) nor Simamora et al. (2021) found it in recently logged forest, and the latter authors considered it among the best indicators of intact mixed dipterocarp forest on Borneo. Degradation and habitat fragmentation are therefore thought to cause additive impacts on this species. In the three generations to 2021, the total population size is thought to have declined by 21-39%, with a best estimate of 30-39% because of the species' predilection for plains-level forest, and its apparent sensitivities to selective logging and habitat degradation. This rate is also precautionarily suspected to continue over the next three generations, although beyond that rates of loss may slow as the percentage area of forest outside protected areas diminishes.
Harpactes orrhophaeus is known from peninsular Thailand, Sabah, Sarawak and Peninsular Malaysia, Kalimantan and Sumatra, Indonesia and Brunei (BirdLife International 2001).
In the Thai-Malay Peninsula, this species is strictly an inhabitant of plains-level forest, below 200 m (Wells 1999, Treesucon and Limparungpatthanakij 2018). On Sumatra, it occurs to 600 m (Eaton et al. 2021) while on Borneo it has been recorded to c.1,500 m and is widely considered a submontane specialist (Mann 2008). However, the species here too is most readily observed below 600 m (eBird 2022). Throughout its range, it favours undisturbed forest (Simamora et al. 2021).
Forest destruction in the Sundaic lowlands of Indonesia and Malaysia has been extensive, for timber and conversion to agriculture. In particular the rapid expansion of oil palm has driven the conversion of the majority of remaining lowland forest in the region. Between 2009 and 2021, tree cover was reduced in its range by 21–26% (Global Forest Watch 2022, based on data from Hansen et al. [2013] and methods disclosed therein). Most of this loss has occurred within the lowlands, where the highest densities of the species would be expected. Moreover, the impact of forest degradation will have added to rates of decline. Associated with the forest loss has been an increase in fire frequency, extent and severity, particularly during strong El Nino events (as in 1998).
Conservation Actions Underway
No targeted conservation actions are known for this species, although it occurs in a number of protected areas.
Conservation Actions Proposed
Conduct repeated surveys throughout the range in order to determine rates of population decline and range contraction. Ensure that remaining tracts of lowland closed-canopy forest in Peninsular Thailand and Malaysia receive adequate protection.
Text account compilers
Berryman, A.
Contributors
Benstead, P., Gilroy, J. & Taylor, J.
Recommended citation
BirdLife International (2024) Species factsheet: Cinnamon-rumped Trogon Harpactes orrhophaeus. Downloaded from
https://datazone.birdlife.org/species/factsheet/cinnamon-rumped-trogon-harpactes-orrhophaeus on 23/12/2024.
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 23/12/2024.