This is part of a consultation on the Red List implications of extensive changes to BirdLife’s taxonomy for passerines
Lynx Edicions and BirdLife International will soon publish the second volume of the HBW-BirdLife Illustrated Checklist of the Birds of the World, building off the Handbook of the Birds of the World series, and BirdLife’s annually updated taxonomic checklist.
The new Checklist will be based on the application of criteria for recognising species limits described by Tobias et al. (2010). Full details of the specific scores and the basis of these for each new taxonomic revision will be provided in the Checklist.
Following publication, an open and transparent mechanism will be established to allow people to comment on the taxonomic revisions or suggest new ones, and provide new information of relevance in order to inform regular updates. We are also actively seeking input via a discussion topic here regarding some potential taxonomic revisions that currently lack sufficient information.
The new Checklist will form the taxonomic basis of BirdLife’s assessments of the status of the world’s birds for the IUCN Red List. The taxonomic changes that will appear in volume 2 of the checklist (for passerines) will begin to be incorporated into the 2016 Red List update, with the remainder to be incorporated into subsequent Red List updates.
Preliminary Red List assessments have been carried out for the newly split or lumped taxa. We are now requesting comments and feedback on these preliminary assessments.
Eastern Double-collared Sunbird Nectarinia mediocris is being moved to genus Cinnyris and split into C. mediocris and C. usambaricus, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, Eastern Double-collared Sunbird was listed as Least Concern, on the basis that it did not approach the threshold for Vulnerable under any criterion. Cinnyris mediocris (as defined now following the taxonomic change) is commonly found in upland forest, bamboo, heath, grassland and gardens in western and central Kenya, as well as northern Tanzania (Cheke and Mann 2016). It is not thought to approach the threshold for Vulnerable under any criterion and so it is proposed that it be listed as Least Concern.
C. usambaricus is found in the Usambara and South Pare Mountains of northern Tanzania and the Taita Hills of southern Kenya (Cheke et al. 2001). It inhabits montane habitats such as forest, heath and grassland, and can be commonly found (see Cheke and Mann 2016). While this species can utilise a range of habitats, forest within its range has been and continues to be degraded as subsistence agriculture and wood extraction encroaches (Goodmanet al.1995, Brooks et al. 1998, Mulwa 1998). Therefore, the quality of its habitat may be decreasing, and coupled with its moderately small and fragmented range this species may qualify as Vulnerable, or Near Threatened, under criterion B1ab(iii).
Comments are invited on these proposed categories and further information would be welcomed.
Brooks, T., Lens, L., Barnes, J., Barnes, R., Kageche Kihuria, J. and Wilder, C. 1998. The conservation status of the forest birds of the Taita Hills, Kenya. Bird Conservation International 8: 119-139.
Cheke, R. and Mann, C. 2016. Eastern Double-collared Sunbird (Cinnyris mediocris). 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/60034 on 30 September 2016).
Cheke, R. A., Mann, C. F. and Allen, R. 2001. Sunbirds. A Guide to the Sunbirds, Flowerpeckers, Spiderhunters and Sugarbirds of the World. Christopher Helm, London.
Goodman, S. M., Stanley, W. T., Newmark, W. D. and Howell, K. M. 1995. The Ambangulu Forest, West Usambara Mountains, Tanzania: a threatened Eastern Arc forest. Oryx 29: 212-214.
Mulwa, R. 1998. An ornithological survey of Mt Kasigau Forest with particular emphasis on Taita White-eye Zosterops poliogaster silvanus in Taita Tareta District, Kenya. In: Bytebier, B. (ed.), Taita Hills Biodiversity Project Annual Report Second Year (November 1997–October 1998), pp. Appendix 10.2.9. National Museums of Kenya, Nairobi.
Tobias, J. A., Seddon, N., Spottiswoode, C. N., Pilgrim, J. D., Fishpool, L. D. C. and Collar, N. J. 2010. Quantitative criteria for species delimitation. Ibis 152: 724–746.