Justification of Red List Category
This species is listed as Data Deficient because it is known from only two specimens and a limited number of recent sightings, thus there is insufficient information available for assessment of its threat status.
No population estimates are available.
The population trend is unknown, due to the extreme paucity of records: it is only ever located at the site of the rediscovery and even then very infrequently (Y. Muzika in litt. 2020).
Carpodacus sillemi was described from two specimens collected in 1929 on a barren plateau at 5,125 m in southern Xinjiang Autonomous Region, China (in an area under Chinese administration but also claimed by India). One of the birds collected was a juvenile with wings not yet fully grown and the collector considered that the birds had either bred close to where they were collected or on the nearby peaks in the Kunlun Shan range. In 2012 it was rediscovered c.1,350 km. away from the type locality in the Yeniugou Valley, in a remote area of western Qinghai, China (Kazmierczak and Muzika 2012), with further sightings the following year in the Yeniugou Valley (Muzika 2014). During the 2013 survey the species was not located anywhere apart from in the Yeniugou Valley (Muzika 2014), and searches elsewhere have failed to find the species (Muzika 2014, J. Hornskov in litt. 2016). However, the survey did conclude that even at appropriate altitudes the species was very difficult to locate (Muzika 2014), and so it is presumably localised and scarce. More recently in 2018, 2 pairs were however observed in close range at Yenigou Valley at 5,025 m (H. Jännes  per G. Sangster in litt. 2020).
The type-locality is a barren plateau at 5,125 m. Sightings in the Yeniugou Valley in 2012 and 2013 were made between 4,950 m and 5,007 m (Kazmierczak and Muzika 2012, Muzika 2014). The 2012 and 2013 sightings were made on a damp, south-facing, low-gradient slope with a rich ground vegetation compared to the rest of the area (Muzika 2014). Both this species and the related C. roborowskii (Tibetan Rosefinch) were seen to feeding on this vegetation (Muzika 2014), and so they may be restricted to areas where this vegetation occurs at sufficient density (Muzika 2014). C. sillemi and C. roborwskii are also considered to be the highest-altitude sister-species existing (Sangster et al. 2016).The availability of this vegetation may vary seasonally (Muzika 2014) although there is no current evidence to show whether this species makes any movements. However, it is probably resident at the type-locality, as the adult collected was in full moult in September.
No threats are known and there are unlikely to be any in the remote area from which it is known.
Conservation Actions Underway
None is known.
Text account compilers
Westrip, J.R.S., Peet, N., Fernando, E., Symes, A., Benstead, P., Crosby, M., Taylor, J.
Hornskov, J., Kazmierczak, K., Muzika, Y. & Sangster, G.
BirdLife International (2021) Species factsheet: Carpodacus sillemi. Downloaded from http://www.birdlife.org on 18/10/2021. Recommended citation for factsheets for more than one species: BirdLife International (2021) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 18/10/2021.