Archived 2016 topics: Yellow-breasted Brush-finch (Atlapetes latinuchus) is being split: request for information on A. nigrifrons

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.

Yellow-breasted Brush-finch Atlapetes latinuchus is being split into A. latinuchus and A. nigrifrons, following the application of criteria set out by Tobias et al. (2010).

Prior to this taxonomic change, A. latinuchus was listed as Least Concern, on the basis that it did not approach the threshold for Vulnerable under any criterion. A. latinuchus (as defined following the taxonomic change) is found in mid-elevation to highland (1,600-3,700 m) bushy habitats on the border of forest, secondary growth, overgrown pasture and roadside thickets in Colombia, Ecuador, and Peru (Jaramillo 2016). It is considered locally common, and its relative tolerance of disturbed habitats mean it is unlikely to be threatened. It is not thought to approach the threshold for Vulnerable under any criterion and so it is proposed that this species be listed as Least Concern.

A. nigrifrons is found only in the Perija Mountains on the border of Colombia and Venezuela, in mid-montane to high elevation bushy habitats (see Jaramillo 2016). Lower-elevation habitat (below 2,000 m) is under threat from a range of processes; including colonisation, the cultivation of narcotics, ranching and mineral exploitation – which are aided by the roads approaching the Colombian side – [C. J. Sharpe in litt. 1997, 2000, A. Viloria per J. Fjeldså in litt. 1998, Sharpe and Lentino 2008]. It was thought high-elevation habitat was less likely to be affected by these factors, however, such areas are now believed to be being affected by illegal cultivation, causing forest habitats to decline and become fragmented (Renjifo et al. 2002, C. J. Sharpe in litt. 2003).

The pre-split species was thought to be adaptable to disturbed habitats (Jaramillo 2016), and so this species may be able to cope with such some habitat disturbance. However, given the great extent of the habitat conversion and clearance, its population may be declining. As this species may be able to adapt to disturbed habitat, it is unsure to what extent its population may be fragmented within its restricted range, and we request any further information regarding this. In the absence of any information regarding the fragmentation of this species it is not thought to approach the threshold for Vulnerable; however if any evidence exists to show this species may be fragmented or severely fragmented (see IUCN 2001, 2012) this species may qualify to be listed as at least Near Threatened under criterion B1ab(i,ii,iii,v).

References:

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.

Jaramillo, A. 2016. Yellow-breasted Brush-finch (Atlapetes latinuchus). In: del Hoyo, J., Elliott, A., Sargatal, J., Christie, D.A. & de Juana, E. (eds.). Handbook of the Birds of the World Alive. Lynx Edicions, Barcelona. (retrieved from http://www.hbw.com/node/61992 on 26 September 2016).

Renjifo, L. M., Franco-Maya, A. M., Amaya-Espinel, J. D., Kattan, G. H. and López-Lanús, B. 2002. Libro rojo de aves de Colombia. Instituto de Investigación de Recursos Biológicos Alexander von Humboldt y Ministerio del Medio Ambiente, Bogotá, Colombia.

Sharpe, C.J. and Lentino, M. 2008. Piscuiz de Perijá Schizoeaca perijana. In: Rodríguez, J.P. and Rojas-Suárez, F. (eds), Libro Rojo de la fauna Venezolana. Tercera Edición, pp. 150. Provita & Shell Venezuela, S.A., Caracas, Venezuela.

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.

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3 Responses to Archived 2016 topics: Yellow-breasted Brush-finch (Atlapetes latinuchus) is being split: request for information on A. nigrifrons

  1. Thomas Donegan says:

    … although in the paper above, we recommended VU status (extract below):

    Conservation status of the Perijá Brush-
    Finch
    Several decades of security problems in the Serranía de
    Perijá result from its strategic location on the Venezuelan
    border. Contraband, drug trafficking and cultivation are
    all well-known issues. It is also historically a “safe
    haven” for insurgents, restricting access for researchers
    (Malakoff 2004). However, the insurgence in some parts
    of the range has dissipated and safe access is now possible
    to such parts. The Serranía de Perijá is a mountain range
    with two contrasting conservation situations. Divided
    laterally between Colombia and Venezuela, the western
    slope in Colombia has undergone massive ecological
    change with an estimated >95% of mature forest cover
    lost. What little intact forest survives is fragmented and
    degraded, primarily by annual dry season incendiaries that
    run up the steep slopes burning cattle pasturelands.
    By contrast, a large proportion of the Venezuelan eastern
    side of Serranía de Perijá is protected by a National Park
    and until recently was considered relatively intact.
    However, recent satellite imagery and ground surveys
    show that the park is presently undergoing rapid changes,
    with colonization and associated deforestation spreading,
    including from over the Colombian side. Rapid
    deforestation in Venezuela may have been fuelled by the
    increased military presence in Colombia, forcing opium
    growers into Venezuela. This situation is compounded
    because historically the Sierra de Perijá National Park in
    Venezuela is reported to have no active management
    (Rodríguez & Rojas-Suárez 1995).
    Of particular concern in the Serranía de Perijá are the
    subtropics and lower montane forests (1,700-2,400 m)
    where A. nigrifrons primarily occurs. Land at this
    elevation is a premium for agriculture and cattle pasture.
    As a consequence, there is little forest surviving at these
    elevations, and what is found is typically secondary forest
    or heavily fragmented or degraded. Observations in these
    fragments and secondary growth forest could reliably find
    pairs and small parties of A. nigrifrons, especially with
    pishing and playback, although the species was far from
    abundant.
    The new ProAves reserve contains a relatively small
    population (estimated >100 individuals) but a lack of
    protection elsewhere in Colombia and mounting threats in
    Venezuela justify conservation attention on the basis of an
    inference of decline due to threats from narcotics
    cultivation, uncontrolled colonization and cattle-ranching
    causing the loss and fragmentation of habitat. It is
    therefore recommended that Atlapetes nigrifrons be listed
    on a precautionary basis as Vulnerable (VU: A2a,c; VU:
    B2a,b (i,iii)) with an estimated Area of Occupancy
    estimated to be less than 2,000 km2 – most of which is on
    the Venezuelan side of the border.

  2. James Westrip (BirdLife) says:

    Based on available information, our preliminary proposal for the 2016 Red List would be to adopt the proposed classifications outlined in the initial forum discussion.

    There is now a period for further comments until the final deadline of 28 October, after which the recommended categorisations will be put forward to IUCN.

    Please note that we will then only post final recommended categorisations on forum discussions where these differ from those in the initial proposal.

    The final 2016 Red List categories will be published on the BirdLife and IUCN websites in early December, following further checking of information relevant to the assessments by both BirdLife and IUCN.

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