BirdLife Species factsheet for Socotra Bunting: http://datazone.birdlife.org/species/factsheet/socotra-bunting-emberiza-socotrana
Socotra Bunting, Emberiza socotrana, is endemic to the island of Socotra, Yemen, restricted to only a few localities, predominantly in the higher elevation habitats, though it can be found in the lowlands, particularly in the non-breeding season (Ryan 2017). Restricted to this one island, it is likely vulnerable to invasive predators that are present on Socotra such as feral cats Felis catus and black rats Rattus rattus. Its habitat may also be under threat from the construction of a coastal ring road, those this has not yet damaged any breeding habitats (R. Porter in litt. 2012). Additionally, livestock grazing may be a future threat to the breeding habitat of this species, as if it were to become more widespread in the high altitude breeding range of this species then its habitat may become degraded and fragmented. These potential threats are not yet thought to be impacting on the species, though, and the population trend is currently considered to be stable. The species is currently listed as Vulnerable under criterion D2 (see BirdLife International 2017), but it likely no longer merits listing as such because it appears to cope with invasive species, and any impacts of habitat loss/degradation are unlikely to rapidly lead to this species becoming Critically Endangered or Extinct (a condition for listing as VU D2 [see IUCN Standards and Petitions Committee 2016]).
The species’s status was evaluated as part of a regional Red List for the Arabian Peninsula (Symes et al. 2015), and was assessed to be Near Threatened under criterion B on the basis that it has a small range, but is not currently declining. A re-evaluation of the Extent of Occurrence is likely required, but even if we take a rough value of the Extent of Occurrence to be the whole of Socotra, this would still fall below the threshold EOO size for Endangered (5,000km2). However, the absence of any known declines in population size or habitat means that the species likely does not to warrant listing as threatened under criterion B1. However, it may be appropriate to list is as Near Threatened as there are these potential threats that could impact the species. Additionally, the population size is small; based on an analysis of transect conducted between 1999 and 2011, the population was estimated to be c.3,770 individuals (Porter and Suleiman 2013), which is roughly equivalent to 2,500 mature individuals. Thus, if the species was to undergo a population decline as a result of the above threats, it would be at the borderline of listing as EN/VU under criterion C2a(ii). Therefore, it is proposed that this species be listed as Near Threatened under criteria B1ab(ii,iii,v); C2a(ii), on the basis that even though the species is currently considered to be stable, there are potential threats that could mean that the species is likely to undergo declines in the near future, while the population size and range of this species are sufficiently small that if this were the case then the species would warrant listing under a threatened category.
We welcome any comments regarding this proposed downlisting.
BirdLife International. 2017. Species factsheet: Emberiza socotrana. Downloaded from http://www.birdlife.org on 25/04/2017.
IUCN Standards and Petitions Subcommittee. 2016. Guidelines for Using the IUCN Red List Categories and Criteria. Version 12. Prepared by the Standards and Petitions Subcommittee. Downloadable from http://www.iucnredlist.org/documents/RedListGuidelines.pdf
Porter, R. F.; Suleiman, A. S. 2013. The populations and distribution of the breeding birds of the Socotra archipelago, Yemen: 1. Sandgrouse to Buntings. Sandgrouse 35: 43–81.
Ryan, P. 2017. Socotra Bunting (Emberiza socotrana). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/61878 on 25 April 2017).
Symes, A.; Taylor, J.; Mallon, D.; Porter, R.; Simms, C.; Budd, K. 2015. The Conservation Status and Distribution of the Breeding Birds of the Arabian Peninsula. IUCN, Cambridge, U.K. and Gland, Switzerland, and Environment and Protected Areas Authority, Sharjah, U.A.E.