This is part of a consultation on the Red List implications of extensive changes to BirdLife’s taxonomy for non-passerines
Lynx Edicions and BirdLife International will soon publish 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 1 of the checklist (for non-passerines) will begin to be incorporated into the 2013 Red List update, with the remainder, and those for passerines (which will appear in volume 2 of the checklist), 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.
Houbara Bustard Chlamydotis undulata is being split into C. undulata and C. macqueenii, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, C. undulata (BirdLife species factsheet) was listed as Vulnerable under criterion A2bcd, on the basis that it was estimated to have undergone a rapid population decline (30-49% over three generations [c.20 years]), owing largely to unsustainable hunting levels, as well as habitat degradation.
C. macqueenii is partially migratory and distributed across West Asia (the Middle East), and parts of South Asia, Central Asia and East Asia. A rate of decline in West Asia of c.25% over 20 years was estimated in 2004 (F. Launay pers. comm. 2004, Tourenq et al. 2004) and the species is described as having declined “sharply” in East Asia (O. Combreau in litt. 2012). An overall estimated decline rate in East Asia of c.40-50% over 20 years, as estimated in 2004 (F. Launay pers. comm. 2004, Tourenq et al. 2004), is thought to remain realistic. If c.70% (East Asia) of the total population is declining by 40-50% and c.30% (West Asia) is declining by c.25%, then the overall rate of decline is likely to be around 35-43% over c.20 years. It is therefore suggested that the species be listed as Vulnerable under criteria A2bcd+3cd+4bcd, on the basis that it is thought to be in rapid and on-going population decline (30-49% over three generations [c.20 years]), owing to hunting pressure and habitat degradation.
C. undulata (as defined following the taxonomic change) is widespread in North Africa and occurs in the Canary Islands. It is likely to be listed as being of Least Concern on the basis that it is not thought to approach the thresholds for Vulnerable under any of the IUCN criteria. Although it showed a steady decline of c.25% in the 20 years preceding 2004 (F. Launay pers. comm. 2004), this trend has since been reversed by a successful captive breeding and release programme in east Morocco and west Algeria, and the overall population is now thought to be increasing (O. Combreau in litt. 2012) (at a conservative estimate, by 1-10% over 20 years).
Comments are invited on these suggested categories and further information would be welcomed.
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.
Tourenq, C., Combreau, O., Pole, S. B., Lawerence, M., Ageyev, V.S., Karpov, A. A., Launay, F. (2004) Monitoring of Asian houbara bustard Chlamydotis macqueenii populations in Kazakhstan reveals dramatic decline. Oryx 38: 62-67.
- Arabian Bustard (Ardeotis arabs) and Nubian Bustard (Neotis nuba): request for information
- Archived 2011-2012 topics: Little Bustard (Tetrax tetrax): what are the trends in Russia and Central Asia?
- Woolly-necked Stork (Ciconia episcopus) is being split: list C. episcopus as Vulnerable?
- Archived 2010-2011 topics: Lesser Kestrel (Falco naumanni): downlist to Near Threatened or Least Concern?
- 2011 Red List draft decisions