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 2014 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.
Scaly Kingfisher Actenoides princeps is being split into A. princeps and A. regalis, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, A. princeps (BirdLife species factsheet) was listed as Least Concern on the basis that it was not thought to approach the thresholds for Vulnerable under any of the IUCN criteria. Although this species was estimated to have a restricted range, it was not believed to approach the thresholds for Vulnerable under the range size criterion (Extent of Occurrence of less than 20,000 km2 combined with a declining or fluctuating range size, habitat extent/quality, or population size and a small number of locations or severe fragmentation). Despite the fact that the population trend appeared to be decreasing, the decline was not believed to be sufficiently rapid to approach the thresholds for Vulnerable under the population trend criterion (at least a 30% decline over ten years or three generations). The population size has not been quantified, but it was not believed to approach the thresholds for Vulnerable under the population size criterion (fewer than 10,000 mature individuals with a continuing decline estimated to be at least 10% over ten years or three generations, or with a specified population structure).
A. regalis is known from south-eastern Sulawesi, where it may inhabit primary and secondary hill and montane forest (Fry and Fry 1999, del Hoyo et al. 2001). It appears to be known from only two specimens (BirdLife International, unpublished data), thus information on recent records and visits to its probable range would be extremely useful. It may qualify as Vulnerable under criterion C2a(ii), if it is believed to have a population of fewer than 10,000 mature individuals, forming a single subpopulation, and is projected to undergo a continuing decline owing to expected habitat loss and degradation in montane regions. Given the apparent scarcity of the species, a preliminary estimate of fewer than 2,500 mature individuals may be justified, in which case it could warrant listing as Endangered under the same criterion.
A. princeps (as defined following the taxonomic change and incorporating erythrorhamphus) inhabits primary and secondary hill and montane forest in northern, central and south-western Sulawesi (Fry and Fry 1999, del Hoyo et al. 2001). It may warrant listing as Near Threatened under criterion A3c, on the basis that it could undergo a moderately rapid population decline (approaching 30% over the next three generations [c.20 years]) owing to expected levels of deforestation in montane areas.
Comments on these suggested categories are invited and further information would be welcomed.
del Hoyo, J., Elliott, A. and Sargatal, J. (2001) Handbook of the birds of the world, Vol 6: Mousebirds to Hornbills. Barcelona, Spain: Lynx Edicions.
Fry, C. H. and Fry, K. (1999) Kingfishers, bee-eaters & rollers. Princeton, NJ: Princeton University Press.
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.