Justification of Red List Category
The small population of this poorly-known parrot occupies a small range (at few locations), which is decreasing in size and degrading in quality as a result of habitat loss, at least at the lower fringes of its altitudinal distribution. The population is suspected to be declining, and it therefore meets the threshold for Vulnerable status.
The population is estimated to number 2,500-9,999 mature individuals based on an assessment of known records, descriptions of abundance and range size. This is consistent with recorded population density estimates for congeners or close relatives with a similar body size, and the fact that only a proportion of the estimated Extent of Occurrence is likely to be occupied. This estimate is equivalent to 3,750-14,999 individuals, rounded here to 3,500-15,000 individuals.
There are no trend data available for this species. However, suitable habitat continues to decline slowly and it has been recorded in domestic trade. Therefore, the species's population is suspected to be declining.
Tanygnathus gramineus is endemic to the island of Buru in South Maluku, Indonesia. There are very few recent records from few localities, despite survey efforts (M. Poulsen in litt. 2012). There were two encounters in 1980 and two more in 1995 on Buru; one bird recorded as a pet on Bali in 2001 (Collar 2006), and a few possible sightings and aural records since (M. Poulsen in litt. 2012). According to early accounts, it was probably not uncommon, and the fact that recent searches have met with little success suggests it may have declined. However, there have been several recent records (Robson 2013, C. Robson in litt. 2016). Some recent reports of the species (Persulessy 2010) are suspected to actually refer to Great-billed Parrot Tanygnathus megalorynchos (Arndt 2011).
This poorly-known species inhabits montane forest, chiefly above 1,000 m, but at least occasionally down to 600 m, or even the lowlands. There are suggestions it may be nocturnal, although this is unproven (T. Arndt in litt. 2012), and there is a recent daytime record (Robson 2013). Although assumed to be resident, it perhaps makes altitudinal movements seasonally, or even daily.
Habitat loss appears to be the main threat. Most forest in the coastal lowlands of Buru has now been cleared, and much of the forest in the northern part of the island has been selectively logged or degraded and fragmented by shifting agriculture, such that only a few small patches of primary lowland forest remain. Montane forest on the island is largely undisturbed, although none currently receives formal protection. There is historical documentation of some minor exploitation of the species, but around 1980 there was no evidence of any trade. It has since been observed as a cage bird on Bali in 2001 (Collar 2006).
Conservation Actions Underway
CITES Appendix II. Surveys for Buru's endemic birds were conducted in 1989 and 1995-1996, this species only being recorded during the latter survey. An area of 1,450 km2, encompassing Gunung Kelapatmada in the west of the island (where the species is known to occur), is proposed as a reserve. However, it remains to be confirmed that this site is the most appropriate area for the conservation of threatened endemic birds.
40-42 cm. Partially nocturnal, forest-dwelling parrot. Male generally dull green with large red bill and black line on lores. Crown and upper cheeks lightly washed bluish-grey. Dull bluish-green wings. Female has pinkish grey bill. Similar spp. Great-billed Parrot T. megalorynchos has blue rump, yellow fringes to wing feathers and larger bill. Male Eclectus Parrot Eclectus roratus is bright green, with short tail and no black on lores. Voice Harsh, high-pitched, slightly drawn-out flight call.
Text account compilers
Tobias, J., Derhé, M., Martin, R, Westrip, J., Benstead, P., Davidson, P., Bird, J., Khwaja, N.
Collar, N., Arndt, T., Robson, C., Poulsen, M.
BirdLife International (2019) Species factsheet: Tanygnathus gramineus. Downloaded from http://www.birdlife.org on 08/12/2019. Recommended citation for factsheets for more than one species: BirdLife International (2019) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 08/12/2019.