Justification of Red List Category
The population of this species, which is small, is undergoing a continuing decline and has disappeared from multiple previous occupied sites. The rate of population reduction is suspected to be rapid, driven principally by intense hunting in much of its range. It may now be close to extinction on Roti Island. As a result, it is classified as Endangered.
The species occurs very patchily and is absent from areas of apparently suitable habitat. Its global population is precautionarily estimated to lie within the band 1,000-3,000 individuals based on a compilation of previous counts and expert opinion of likely numbers in all occupied sites (C. Trainor in litt. 2012), roughly equivalent to 660-2,000 mature individuals. The largest numbers occur in eastern Timor-Leste, where the total in Nino Konis Santana National Park is estimated to be in the low hundreds, although encounter rates were slightly lower during visits in 2019 (10 records of 1-25 birds) than in 2003-2004 (C. Trainor and J. P. Lopez in litt. 2020). Fewer than 50 are now estimated to be present on Roti (Verbelen et al. 2017), and the actual number may be only a handful given the lack of recent records (C. Trainor and J. P. Lopez in litt. 2020). On Atuaro the species is present (Trainor and Soares 2004) and there is an undocumented record on eBird from 2013 (eBird 2021), but it appears to be very scarce if there is an extant population.
Clearance of lowland forest has greatly reduced the extent of suitable habitat for the species, but intense hunting pressure is the main factor in the rapid and continuing decline in this species's population. The stronghold of the population is now in northeastern Timor-Leste, where encounter rates and total numbers in 2018-2019 were similar or slightly lower than found in 2003 (C. Trainor & J. P. Lopez in litt. 2020). Elsewhere in the range the species has almost disappeared. There have been no documented or confirmed records from West Timor since 1999, and the Bipolo forest is now only a tiny remnant. The species is believed to have been lost from both this site and Camplong, where it was present at the beginning of the 21st century (C. Trainor & J. P. Lopez in litt. 2020). On Roti Island, records have been few despite numerous observers searching the forested northern part of the island (Verbelen & Cooleman 2015). The most recent record appears to be that from 2013 (Verbelen & Cooleman 2015), with no records from ten days in northern Roti in 2018-19 (C. Trainor in litt. 2020). It appears that hunting has virtually eliminated the species from this island.
Treron psittaceus is endemic to Timor-Leste, West Timor and its satellite islands, Semau (42 records in total but none observed in recent visits C. Trainor in litt. [2016, 2020]), Atauro (Trainor & Soares 2004) and Roti, Nusa Tenggara, Indonesia, where it appears to be uncommon or rare (BirdLife International 2001), and may now be close to extinction (Verbelen and Cooleman 2015, C. Trainor in litt. 2020).
It is an infrequently recorded species, which is ascribed to inconspicuous habits but may equally be due to very low population densities caused by hunting. For example, extensive surveys in Onansila in 1991 resulted in just a single record [Johnstone et al. 2014]). In West Timor the last confirmed record was in 1999, though there is a more recent undocumented record from the now tiny Bipolo Forest in late 2019 (eBird 2021). Timor-Leste is the species's stronghold (Trainor et al. 2004), where it was described as scarce to moderately common at all locations visited during survey work in 2003 (Mauro 2003). Hunting appears to have caused a rapid population decline, such that there are now few records from only scattered locations even here (C. Trainor and J. P. Lopez in litt. 2020). On Roti it appears to have been rare for at least several decades—the first was recorded in 1969 (Mees 1975), subsequently there have been only a handful of records of small numbers (Trainor 2005, Verbelen and Cooleman 2015). However more than 40 days of observations in 2018-2019 resulted in zero observations, suggesting that any remaining population must now be tiny if it even persists (C. Trainor in litt. 2020).
It inhabits primary and tall secondary, lowland dry and monsoon-forest, mostly in the extreme lowlands, straggling up to 1,000 m (Mauro 2003, Trainor and Soares 2004, C. Trainor in litt. 2007). It is likely to be nomadic in response to the fruiting cycle of figs, and is usually encountered in small flocks containing tens of birds, exceptionally up to 140 individuals (C. Trainor in litt. 2007). This flocking behaviour makes it vulnerable to local hunters who are aware of their call (C. Trainor in litt. 2016). Elevation range is 0-1080 m (n=42), with an average of 167 m. The only two records above 500 m were at Mt Legumau and Lautem or Lospalos district (C. Trainor in litt. 2016).
Following the loss of monsoon-forest from the majority of the range, the primary threat now is intensive hunting of the species in the remaining accessible fragments.
The mountains of Timor-Leste were heavily deforested early in the 20th century, then what remained or had re-established was rapidly reduced further during Indonesian rule (1975-1999). Monsoon-forests now only cover an estimated 4% of West Timor, scattered in around seven unprotected patches that are continually declining in size due to intensive grazing and burning.
Pigeons (including this species, which local hunters describe as delicious) are hunted extensively in Timor and guns are widely available (C. Trainor in litt. 2007). It is also a principal target of hunters on Roti where hunting pressure is intense (Trainor 2005, C. Trainor and J. P. Lopez in litt. 2020). With effectively all habitat now accessible to hunters (although nominally Nino Konis Santana National Park is protected) further local extirpation is expected, and indeed may have recently occurred on Roti (C. Trainor and J. P. Lopez in litt. 2020).
Conservation Actions Underway
Recent surveys have identified several areas in West Timor to be of conservation importance to the island's endemic avifauna, of which, Bipolo (although now only c.1 km2), and Camplong, previously supported the species but it is now feared the species is lost from both. Another site, Gunung Timau, is subject to an initiative to include it within the Gunung Mutis protected area: it is possible a small population persists in this area. Surveys in Timor-Leste located it at approximately ten sites in the early 2000s (C. Trainor in litt. 2007). The recently designated Nino Konis Santana National Park supports a population estimated to number at most in the low hundreds (C. Trainor in litt. 2007, 2020).
28 cm. Medium-sized, arboreal, green pigeon. Male slightly greyish-green, brighter on throat, rump and uppertail-coverts. Greyish-black wings with coverts fringed yellow. Green central tail-feathers, remainder grey with darker band. Vent and undertail-coverts white, tipped green. Female duller green with paler yellow wing-covert fringes. Similar spp. Only other green-coloured pigeon in range is Rose-crowned Fruit-dove Ptilinopus regina, and this has orange and yellow patches on underparts and pink crown in the male. Voice Series of 6-7 accelerating, descending see-saw notes and medley of high-pitched bubbling and gargling sounds.
Text account compilers
Bird, J., Lopez, J. P. L., Trainor, C. & Verbelen, F.
BirdLife International (2023) Species factsheet: Treron psittaceus. Downloaded from http://www.birdlife.org on 31/03/2023. Recommended citation for factsheets for more than one species: BirdLife International (2023) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 31/03/2023.