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.
Silvery Grebe Podiceps occipitalis is being split into P. occipitalis and P. juninensis, following the application of criteria set out by Tobias et al. (2010).
Prior to this taxonomic change, P. occipitalis (BirdLife species factsheet) was listed as being of Least Concern, on the basis that it was not thought to approach the thresholds for Vulnerable under any of the IUCN Red List criteria.
P. juninensis inhabits the Andean highland from Antofagasta (and occasionally Santiago) in northern Chile and Catamarca in north-western Argentina to Junín in Peru (casually descending to the coast of Peru), with a few breeding sites further north in Peru, Ecuador and the Cordillera Central of Colombia (Fjeldså 2004).
The species’s population is said to have become very localised north of the Bolivian-Peruvian Altiplano, and it may be vanishing from the páramos of northern Peru, Ecuador and Colombia (Fjeldså 2004). The population on Lake Mica in Ecuador appears to have declined markedly in recent years. Threatening processes include the modification, pollution and siltation of wetlands, as well as the potential impacts of introduced species (Fjeldså 2004). In Colombia, the species is in decline owing to habitat conversion and introduced species (Renjifo et al. 2002). Owing to these observed declines, juninensis has been regarded as threatened (Vulnerable) (Fjeldså 2004).
It is suggested that this species be listed as Near Threatened or Vulnerable under criteria A2ce;3ce;4ce, on the basis that it is suspected to be undergoing a population decline approaching or exceeding 30% over three generations (c.21 years).
P. occipitalis (as defined following the taxonomic change) is found from Tierra del Fuego up to the Pampas, and to Cordoba and Santa Fé in Argentina, migrating north to northern Argentina, southern Paraguay and extreme southern Bolivia, and also occurs in semi-arid central Chile, where it nests when water levels are high (Fjeldså 2004, Guyra Paraguay 2005, Tobias and Seddon 2007). It is thought 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 Red List criteria.
Comments on these suggested categories are invited and further information would be welcomed.
Fjeldså, J. (2004) The Grebes. Oxford, UK: Oxford University Press.
Guyra Paraguay (2005) Atlas de las aves del Paraguay. Asunción, Paraguay: Asociación Guyra Paraguay.
Renjifo, L. M., Franco-Maya, A. M., Amaya-Espinel, J. D., Kattan, G. H. and López-Lanús, B. (Eds) (2002) Libro rojo de aves de Colombia. Bogatá, Colombia: Instituto Humboldt Colombia and Ministerio del Medio Ambiente.
Tobias, J. A. and Seddon, N. (2007) Ornithological notes from southern Bolivia. Bulletin of the British Ornithologists’ Club 127: 293–300.
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.