LC
Socotra Sunbird Chalcomitra balfouri



Justification

Justification of Red List Category
Although this species may have a small range, it is not believed to 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 has not been quantified, but it is not believed to 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
The global population size has not been quantified, but the species is described as common (Cheke et al. 2001).

Trend justification
The population is suspected to be in decline owing to habitat degradation through intense grazing and wood clearance for timber.

Distribution and population

This species is endemic to Socotra, Yemen. The highest recorded density and numbers (50 individuals) recorded during the 1993 survey of eastern Socotra were at Wadi Ayhaft (Porter et al. 1996) in the northern foothills of the Hagghier (=Haghir) range.

Ecology

This species occurs from sea level to at least 1,370 m in all major habitat types and plant associations, including parkland dominated by the endemic tree Dracaena cinnabari (Showler and Davidson 1996), and is recorded at the highest densities and numbers in mixed subtropical and drought-deciduous mesic-montane woodland and scrub, where it is usually seen in pairs (Porter and Martins 1996, Showler and Davidson 1996, Davidson 1996). There is limited recent information on its breeding biology, although observations of juveniles would suggest eggs are laid at the beginning of March (Showler and Davidson 1996). However, young have been found in a nest as late as May (Forbes-Watson 1964). The nest is dome-shaped, usually hidden in a tree fork, with an oval shaped entrance, constructed of woven grass and cobwebs and lined with silky plant material (Showler and Davidson 1996). Food consists mainly of arthropods with occasional fruit and berries. Nectar seems to be a less important food source than might be expected (Showler and Davidson 1996).

Threats

Habitat degradation and diminishment through grazing may impact upon population levels; much of the climax vegetation on Socotra has been destroyed through intense grazing and wood clearance for timber.

Acknowledgements

Text account compilers
Ekstrom, J., Butchart, S., Harding, M., Fisher, S.


Recommended citation
BirdLife International (2020) Species factsheet: Chalcomitra balfouri. Downloaded from http://www.birdlife.org on 02/04/2020. Recommended citation for factsheets for more than one species: BirdLife International (2020) IUCN Red List for birds. Downloaded from http://www.birdlife.org on 02/04/2020.