Blue Rock-thrush Monticola solitarius


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). The population trend appears to be stable, and hence the species does not approach the thresholds for Vulnerable under the population trend criterion (>30% decline over ten years or three generations). The population size is very large, and hence does not 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
In Europe, the breeding population is estimated to number 110,000-237,000 pairs, which equates to 219,000-474,000 mature individuals (BirdLife International 2015). Europe forms c.15% of the global range, so a very preliminary estimate of the global population size is 1,460,000-3,160,000 mature individuals, although further validation of this estimate is needed. National population estimates include: c.10,000-100,000 breeding pairs, c.1,000-10,000 individuals on migration and c.1,000-10,000 wintering individuals in China; c.100-10,000 breeding pairs, c.1,000-10,000 individuals on migration and c.1,000-10,000 wintering individuals in Taiwan; c.10,000-100,000 breeding pairs and c.1,000-10,000 individuals on migration in Korea; c.10,000-100,000 breeding pairs in Japan and possibly c.100-100,000 breeding pairs and c.50-10,000 individuals on migration in Russia (Brazil 2009).

Trend justification
The population is suspected to be stable in the absence of evidence for any declines or substantial threats. The European population trend is unknown (BirdLife International 2015).


During the breeding season this species is found on precipitous cliffs, in steep rocky valleys and defiles, ravines and gorges, on crags, outcrops, arid boulder-strewn slopes, sea cliffs and headlands, rocky coasts, ruins, quarries and open mines, isolated stone buildings, churches in rural valleys. In areas of southern Europe where Turdus merula is absent it frequents the roofs of houses, churches, castles and monuments and will occasionally invade urban environments. The key habitat features for this species appear to be vertical faces (cliffs, buildings) and diverse vegetation over 20-80% of area. In Europe, during the winter it may occupy habitats rarely used for breeding, such as olive orchards. Breeding occurs March-July in north-west Africa, end April to mid-July in Iberia, end February to mid-June in Israel, June-July in Afghanistan, April-July in Himalayas, May-July in China, at least April-May in Japan, January-May in Peninsular Malaysia, April-June in northern Philippines and to July in south-east Asia. The nest is a shallow cup or rough pad of coarse dry grass, rootlets, moss and leaves, loosely constructed and lined with fine soft grass, rootlets and occasional feathers and plant down. It is generally sited under a rock overhang, in a crevice of cliff, rock, bank, cave or building and sometimes in a tree hole, generally two to five metres above ground. Clutches are three to six eggs. It feeds on invertebrates, small vertebrates and fruit. The species is sedentary, a partial migrant, altitudinal migrant and intercontinental migrant (Collar 2015).


From 1970 to 1990 the species suffered declines in Spain and Italy as a result of new coastal tourist developments, flooding of canyons and gorges for reservoirs, renovation of old towers and churches, and afforestation and regrowth of matorral following pastoral abandonment. However in Spain these pressures do not explain declines in all areas (Collar 2015). Persecution in Malta, including nest robbing and catching of birds, and human disturbance, has driven the species to occupy inaccessible coastal areas (Tucker and Heath 1994, Collar 2015).

Conservation actions

Conservation Actions Underway
CMS Appendix II. Bern Convention Appendix II. There are currently no known conservation measures for this species within its European range.

Conservation Actions Proposed
Conservation measures for this species should include the protection of habitat in coastal regions and long inland river systems. Basic information on population numbers should be obtained through census and monitoring work, especially in Portugal, Italy, Turkey and Greece. Research is needed to investigate reasons for declines in areas where the causes are not apparent (Tucker and Heath 1994).


Text account compilers
Ashpole, J, Butchart, S., Ekstrom, J.

Recommended citation
BirdLife International (2024) Species factsheet: Monticola solitarius. Downloaded from on 24/02/2024.
Recommended citation for factsheets for more than one species: BirdLife International (2024) IUCN Red List for birds. Downloaded from on 24/02/2024.