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.
Red-headed Weaver Anaplectes rubriceps is being split into A. rubriceps, A. leuconotos and A. jubaensis, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, A. rubriceps was listed as Least Concern, on the basis that it did not approach the threshold for Vulnerable under any criterion. A. rubriceps (as defined following the taxonomic change) is found across large areas in central-southern Africa, occurring in Angola, Democratic Republic of Congo, Tanzania, Zambia, Malawi, Mozambique, Namibia, Botswana, Zimbabwe, South Africa and Swaziland in wooded or bushveld habitats (Craig and de Juana 2016). A. leuconotos is found further north of A. rubriceps, occurring across from west Africa in Mali to east Africa in Kenya and Tanzania in wooded and bushy habitat, as well as savannah and gardens (Zimmerman et al. 1996, Craig and de Juana 2016). While A. leuconotos may be relatively rare in west Africa (see Craig and de Juana 2016) elsewhere it may be local to uncommon (Zimmerman et al. 1996), and A. rubriceps may be locally common (Craig and de Juana 2016). In the absence of any evidence for declines or substantial threats, neither of these species is thought to approach the threshold for Vulnerable under any criterion, and therefore it is proposed that they both be listed as Least Concern.
A. jubaensis is found in the lowlands of Somalia, along the Jubba River, and into northern Kenya in moist coastal bush south to Kiwayu (Zimmerman et al. 1996, Redman et al. 2011). Riverine woodland in Somalia is highly threatened owing to conversion to agriculture and fuelwood collection (Ash and Miskell 1998; Madgwick 1986), and so this species may be in decline. It is described as localised (Zimmerman et al. 1996, Redman et al. 2011), but its global population size has not been quantified. Given its restricted range the population size is not thought to be very large, however, we request further information regarding population size estimates, and whether there is any evidence to show this species may be in decline. In the absence of any further information this species is unlikely to meet the threshold for Vulnerable and would warrant listing as Least Concern.
Comments are invited on these proposed categories and further information would be welcomed.
Ash, J. S. and Miskell, J. E. 1998. Birds of Somalia. Pica Press, Robertsbridge, U.K.
Craig, A. & de Juana, E. 2016. Red-headed Weaver (Anaplectes rubriceps). 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/61079 on 26 September 2016).
Madgwick, J. 1986. Somalia research project: an ecological study of the remaining areas of riverine forest in the Jubba valley, Southern Somalia. University College London, London.
Redman, N., Stevenson, T. and Fanshawe, J. 2011. Birds of the Horn of Africa. Ethiopia, Eritrea, Djibouti, Somalia and Socotra. 2nd Edition. Christopher Helm, London.
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.
Zimmerman, D. A., Turner, D. A. and Pearson, D. J. 1996. Birds of Kenya and northern Tanzania. Christopher Helm, London.