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-headed Bulbul Pycnonotus atriceps is being moved to genus Brachypodius and being split into B. atriceps and B. fuscoflavescens, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, Black-headed Bulbul was listed as Least Concern on the basis that it did not approach the threshold for Vulnerable under any criteria. Brachypodius atriceps (as now defined following the taxonomic change) is found throughout South East Asia; occurring from east Bangladesh and north-east India down to Vietnam and peninsula Malaysia, as well as being found on the Greater Sundas, west Philippines Islands, west Sumatran Islands, and Bawean and Maratua Islands (Fishpool and Tobias 2016a). It is found in a range of forest and woodland habitats, as well as in gardens, and is frequently found in areas where forest is more open or disturbed, such as by waterways or roads (Fishpool and Tobias 2016a). It is locally common throughout its range, and is not thought to approach the threshold for Vulnerable under any criterion. Therefore, it is proposed that it be listed as Least Concern.
B. fuscoflavescens is found on the Andaman Islands, India, in evergreen and deciduous forest as well as at forest edges and secondary growth (Fishpool and Tobias 2016b). Its Extent of Occurrence is limited to c.6,600 km2, and population assessments for this species range from it being abundant through to it being rare (Fishpool and Tobias 2016b); although it is most likely ‘locally common’ (Fishpool and Tobias 2016b). Habitat loss continues on the Andaman Islands as a result of land development to support a growing human population (Reddy et al. 2016). Therefore, given the species’s restricted range, it is suggested that this species be listed as Near Threatened under criterion B1ab(ii,iii,v); and we welcome any further information regarding population size estimates.
Comments are invited on these proposed categories and further information would be welcomed.
Fishpool, L. and Tobias, J. 2016a. Black-headed Bulbul (Pycnonotus atriceps). 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/57926 on 13 September 2016).
Fishpool, L. & Tobias, J. 2016b. Andaman Bulbul (Pycnonotus fuscoflavescens). 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/57927 on 13 September 2016).
Reddy, C. S., Jha, C. S., Dadhwal, V. K., Krishna, P. H., Pasha, S. V., Satish, K. V., Dutta, K., Saranya, K. R. L., Rakesh, F., Rajashekar, G. and Diwakar, P. G. 2016. Quantification and monitoring of deforestation in India over eight decades (1930-2013). Biodiv. And Conserv. 25: 93-116.
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.