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.
Great Shortwing Heinrichia calligyna is being split into H. calligyna and H. simplex, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, Heinrichia calligyna (BirdLife species factsheet) was listed as Least Concern, on the basis that although it has a restricted range, it was not considered to approach the thresholds for listing as Vulnerable under any criteria. The pre-split species was characterised as infrequently encountered and generally uncommon, but common to abundant at the upper levels of its elevational range (Collar 2016). The habitat is dense undergrowth of montane forest from 1,500 to 3,500 m altitude.
H. simplex is found only at high altitudes along the northern ‘arm’ of Sulawesi, in the Tentolo-Matinan Mountains (not at Loro Lindu or other areas of north-central Sulawesi), while H. calligyna (as defined following the taxonomic change, and incorporating picta) is found throughout the highlands of central and west Sulawesi, and also in the highest areas of south east Sulawesi.
The newly split H. simplex has recently been observed near the location of the type specimen along the Ile-ile track in the Tentolo-Matinan Mountains (Rasmussen 2016). However there do not seem to be records from anywhere else, nor further specimens. High altitude areas seem poorly studied (or reported) in this region. The area of habitat above 1,500 m within the species’ range may actually be very small, and there do not appear to be records for the few locations that are visited (Gunung Ambang and Mahawu for example). Accordingly, the new species may actually prove to only occur within a very restricted range within the Tentolo-Matinan Mountains, within which there is only approximately 86 km2 in total above 1,500 m. The area above 1,700 m, where the species was observed to be common (Rasmussen 2016) is around 30km2.
Within the range of the species there has been some habitat loss due to gold prospecting and mining but generally there has been little modification of the high altitude areas in which the species occurs. Accordingly the population is considered to be stable, and it may well be common within this small area.
In the absence of a decline, but in the face of a deal of uncertainty and a potentially tiny range, it is proposed that H. simplex be listed as Near Threatened on the basis that the population may approach the thresholds for listing as Vulnerable under criterion D1.
Further information on the distribution and abundance of the species is required.
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.
IUCN. 2012. Guidelines for Application of IUCN Red List Criteria at Regional and National Levels: Version 4.0. Gland, Switzerland and Cambridge, UK: IUCN.
Rasmussen, P. 2016. eBird Checklist: http://ebird.org/ebird/view/checklist/S24826057. eBird: An online database of bird distribution and abundance [web application]. eBird, Ithaca, New York. Available: http://www.ebird.org. (Accessed: Date 7th October 2016).
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.