The initial deadline for comments on this topic is 28 April 2014, and therefore later than for most other topics currently under discussion.
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.
Philippine Dwarf-kingfisher Ceyx melanurus is being split into C. melanurus and C. mindanensis, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, C. melanurus (BirdLife species factsheet) was listed as Vulnerable under criteria A2c+3c+4c, on the basis that it was suspected to be undergoing a rapid population decline, of 30-49% over 13 years (estimate of three generations), owing to on-going and extensive deforestation throughout its range. The pre-split species was characterised as generally scarce, with an estimated population of 10,000-19,999 mature individuals, although it may be under-recorded owing to its secretive behaviour.
C. mindanensis is found on Mindanao and Basilan, while C. melanurus (as defined following the taxonomic change, and incorporating samarensis) is found on Luzon, Alabat, Catanduanes, Polillo, Samar and Leyte.
Both of the newly defined species occur in primary and secondary forest in the lowlands and foothills (Kennedy et al. 2000).
Deforestation in the Philippines is reported to have been very rapid in recent decades, and it is said that the country lost c.40% of its forest cover in the 20 years between 1970 and 1990 (Uitamo 1999). Data from ESSC (Environmental Science for Social Change) suggest that the area of closed-canopy forest in the Philippines decreased by c.44% between 1987 and 2002 (Walpole 2010). Data from the Philippines government do not corroborate these apparently steep declines in forest cover.
It is suggested that both of the newly-defined species be listed as Vulnerable under criteria A2c+3c+4c, on the basis that they are suspected to be undergoing rapid declines. It is possible, however, that these suggested assessments are over pessimistic, as deforestation rates in parts of the Philippines may have slowed in recent years. Nevertheless, these species appear to occur at low population densities, with C. mindanensis possibly numbering fewer than 10,000 mature individuals. With this in mind, information is sought on this species’s likely sub-population structure, i.e. whether all sub-populations are likely to number no more than 1,000 mature individuals, where sub-populations are defined as “geographically or otherwise distinct groups in the population between which there is little demographic or genetic exchange (typically one successful migrant individual or gamete per year or less)” (IUCN 2001). This information is sought because the species could qualify as Vulnerable or Near Threatnened under criterion C2a(i).
Comments are invited on these proposed categories and further information would be welcomed.
IUCN (2001) IUCN Red List Categories and Criteria: Version 3.1. Gland, Switzerland and Cambridge, UK: IUCN Species Survival Commission.
Kennedy, R. S., Gonzales, P. C., Dickinson, E. C., Miranda, H. C., Jr. and Fisher, T. H. (2000) A guide to the birds of the Philippines. Oxford, UK: Oxford 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.
Uitamo, E. (1999) Modelling deforestation caused by the expansion of subsistence farming in the Philippines. J. Forest Economics 5(1): 99-122.
Walpole, P. (2010) Figuring the Forest Figures: Understanding Forest Cover Data in the Philippines and where we might be proceeding. Quezon City, Philippines: Environmental Science for Social Change. Downloaded from: essc.org.ph
- Variable Kingfisher (Ceyx lepidus) is being split: list C. dispar as Vulnerable and five other newly defined species as Near Threatened?
- Sulawesi Kingfisher (Ceyx fallax) is being split: list C. sangirensis as Critically Endangered and C. fallax as Near Threatened?
- Rufous Hornbill (Buceros hydrocorax) is being split: list both B. hydrocorax and B. mindanensis as Vulnerable?
- Silvery Kingfisher (Alcedo argentata) is being split and Indigo-banded Kingfisher (A. cyanopectus) is being split: list A. argentata and A. flumenicola as Vulnerable and A. nigrirostris as Near Threatened?
- Philippine Scops-owl (Otus megalotis) is being split: list O. nigrorum as Vulnerable and O. megalotis and O. everetti as Near Threatened?