Archived 2014 discussion: Black-faced Ibis (Theristicus melanopis) is being split: list T. melanopis and T. branickii as Near Threatened or Vulnerable?

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.

Black-faced Ibis Theristicus melanopis is being split into T. melanopis and T. branickii, following the application of criteria set out by Tobias et al. (2010).

Prior to this taxonomic change, T. melanopis (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 criteria.

T. branickii occurs in western Bolivia and southern Peru, with an isolated population in Ecuador, and at least formerly occurred in northern Chile (Lauca: Jaramillo et al. 2003). It inhabits open grasslands, often near rocky outcrops, at 3,700-4,600 m, locally down to 3,000 m (Schulenberg et al. 2007). It has been described as uncommon and very local throughout its range (del Hoyo et al. 1992). Peru appears to be species’s stronghold, where it is described as widespread but uncommon (Schulenberg et al. 2007), and the population there is thought to run to four or five figures (Collar and Bird 2011). In Ecuador, the species is described as rare and very local, with probably fewer than 100 individuals, and said to still be hunted in many areas, although it also occurs in some protected areas (Ridgely and Greenfield 2001).

Given hunting pressure and threats to the species’s habitats, such as degradation and erosion caused by livestock and pollution from mining, it is likely that its population is undergoing a decline, the rate of which is unknown (Collar and Bird 2011), but could be approaching 30% over three generations, estimated by BirdLife to be c.29 years for this species. If evidence were to suggest this, the species would probably qualify as Near Threatened under criterion A. Evidence of a decline of at least 30% over three generations would imply that the species should be listed as Vulnerable under criterion A. Comments and further information are invited, including whether the population is likely to approach or meet the threshold of 10,000 mature individuals.

T. melanopis (as defined following the taxonomic change) is found in southern Argentina and southern and central Chile, with an isolated population in western Peru, and inhabits a variety of open landscape habitats from sea-level to 3,000 m (del Hoyo et al. 1992). It has been characterised as common in southern Chile and Argentina (del Hoyo et al. 1992). In Peru, it is confined to the coast, and was once widespread, but is now almost extirpated (Schulenberg et al. 2007). If a population decline approaching 30% over 29 years (estimate of three generations) were suspected the species would likely qualify as Near Threatened under criterion A. If a decline of at least 30% over 29 years were suspected, the species would probably qualify as Vulnerable. Comments and further information are invited.

References:

Collar, N. J. and Bird, J. P. (2011) Phenotypic discrimination of the Andean Ibis (Theristicus branickii). Wilson Journal of Ornithology 123(3): 459-463.

del Hoyo, J., Elliot, A. and Sargatal, J. (1992) Handbook of the birds of the world, vol 1: Ostrich to Ducks. Barcelona, Spain: Lynx Edicions.

Jaramillo, A., Burke, P. and Beadle, D. (2003) Field guide to the birds of Chile, including the Antarctic Peninsula, the Falkland Islands and South Georgia. London, UK: Christopher Helm.

Ridgely, R. S. and Greenfield, P. J. (2001) The Birds of Ecuador: status, distribution and taxonomy. Ithaca and London: Cornell University Press and Christopher Helm.

Schulenberg, T. S., Stotz, D. F., Lane, D. F., O’Neill, J. P. and Parker, T. A. III (2007) Field guide to the birds of Peru. London, UK: Christopher Helm.

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.

Related posts:

  1. Archived 2014 discussion: Woolly-necked Stork (Ciconia episcopus) is being split: list C. episcopus as Vulnerable?
  2. Archived 2010-2011 topics: Black Tinamou (Tinamus osgoodi): at least Vulnerable, or downlist to Near Threatened?
  3. Archived 2014 discussion: Maroon-faced Parakeet (Pyrrhura leucotis) is being split: list P. leucotis as Vulnerable and P. emma as Near Threatened or Least Concern?
  4. Archived 2011-2012 topics: Neblina Metaltail (Metallura odomae): request for information
  5. Archived 2012-2013 topics: Black-browed Albatross (Thalassarche melanophrys): downlist to Near Threatened?
This entry was posted in Americas, Archive, South America and tagged . Bookmark the permalink.

4 Responses to Archived 2014 discussion: Black-faced Ibis (Theristicus melanopis) is being split: list T. melanopis and T. branickii as Near Threatened or Vulnerable?

  1. T. branickii is more or less common in the Andes of Peru, in pairs or groups, frequently of more than 10 individuals. I do not think the species should be listed, maybe only the populations of Ecuador and Chile

  2. Fernando Angulo says:

    T. melanopis is a very rare species in the peruvian coast. There are few recent records in Piura (Sechura), Lambayeque (Pomac and Tinajones), Arequipa (Mejia) and Tacna (Ite). The reasons for declyining are not clearly understood and I suspect is basically habitat degradation and in small proportion, direct hunting.

  3. Joe Taylor says:

    Preliminary proposals

    Based on available information and comments posted above, our preliminary proposals for the 2014 Red List would be to treat:

    T. melanopis as Least Concern

    T. branickii as Near Threatened under criteria A2cd+3cd+4cd

    There is now a period for further comments until the final deadline of 31 March, after which recommended categorisations will be put forward to IUCN.

    The final Red List categories will be published on the BirdLife and IUCN websites in mid-2014, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  4. Andy Symes says:

    Recommended categorisations to be put forward to IUCN

    Following further review, there have been no changes to our preliminary proposals for the 2014 Red List status of these species.

    The final categorisations will be published later in 2014, following further checking of information relevant to the assessments by BirdLife and IUCN.

Comments are closed.