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.
Black-billed Magpie Pica pica is being split into P. pica, P. asirensis, P. hudsonia and P. mauritanica, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, P. pica was listed as Least Concern, on the basis that it did not approach the threshold for Vulnerable under any criterion. P. pica (as now defined following the taxonomic change), P. hudsonia and P. mauritanica all do not appear to approach the threshold for Vulnerable under any criterion and so warrant listing as Least Concern.
P. asirensis is found only in the highlands of south-west Saudi Arabia in Asir Province (Symes et al. 2015, Babbington 2016). It inhabits juniper forest especially well vegetated upland valleys (Babbington 2016), but these forests are not regenerating and are being cleared for timber and fuel (Symes et al. 2016). The area is also being heavily disturbed by tourism activities and climate change is bringing warmer and drier weather (Symes et al. 2015, Babbington 2016), and so the population size is inferred to be declining. The population size has recently been estimated at 135 pairs or less (270 mature individuals) (Symes et al. 2015, Babbington 2016), and so this species likely warrants at least listing as Endangered under criterion C2a(ii).
Comments are invited on these proposed categories and further information would be welcomed.
Babbington, J. 2016. Update on the status and occurrence of Arabian Magpie Pica pica asirensis in Saudi Arabia. Sandgrouse 38(2): 146-151.
Symes, A., Taylor, J., Mallon, D., Porter, R., Simms, C. and Budd, K. 2015. The conservation status and distribution of the breeding birds of the Arabian Peninsula. IUCN, Cambridge, UK and Gland, Switzerland; Environment and Protected Areas Authority, Sharjah, UAE.
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.