Archived 2016 topics: Rufous Antpitta (Grallaria rufula) is being split: list G. saltuensis as Vulnerable?

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.

Rufous Antpitta Grallaria rufula is being split into G. rufula and G. saltuensis, following the application of criteria set out by Tobias et al. (2010).

Prior to this taxonomic change, G. rufula was listed as Least Concern, on the basis that it did not approach the threshold for Vulnerable under any criterion. G. rufula (as now defined following the taxonomic change) is found across mountainous regions of northern South America, occurring in the Andes in Venezuela, Colombia, Ecudaor and Peru and into Bolivia, as well as in the Santa Marta Mountains in northern Colombia. It is uncommon to locally common in montane forest understorey and forest floor (Krabbe and Schulenberg 2016) and is not thought to approach the threshold for Vulnerable under any criterion. Therefore, it is proposed that it be listed as Least Concern.

G. saltuensis is found only in the Perija Mountains on the border of Colombia and Venezuela, in montane forest understorey and on the forest floor (Krabbe and Schulenberg 2016). While lower-elevation habitat (below 2,000 m) is under threat from a range of processes (including colonisation, ranching, the cultivation of narcotics, and mineral exploitation – which are aided by the roads approaching the Colombian side – [C. J. Sharpein 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 suitable habitat to decline and become fragmented (Renjifo et al. 2002, C. J. Sharpe in litt. 2003). Only patches of montane forest remain on the steepest slopes of the Cerro Pintado, and forest is still being lost to burning and poppy cultivation, while access to the area is difficult due to security issues (R. Strewe in litt. 2003). The population size of this species has not been quantified, but it is thought to be declining due to the ongoing threats in the area, and the overall population size is unlikely to be large given the species’s restricted range with limited habitat available. Therefore, it may qualify as Vulnerable under criterion B1ab(i,ii,iii,v);C2a(ii) if there is evidence to suggest that the population size is less than 10,000 mature individuals and the population has become severely fragmented (IUCN 2001, 2012).

Comments are invited on these proposed categories and further information would be welcomed.

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.

Krabbe, N.K. and Schulenberg, T.S. 2016. Rufous Antpitta (Grallaria rufula). 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/56911 on 23 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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7 Responses to Archived 2016 topics: Rufous Antpitta (Grallaria rufula) is being split: list G. saltuensis as Vulnerable?

  1. Thomas Donegan says:

    I support this split very strongly and am pleased that HBW/BL is giving some leadership on the point, after long-promised studies on the group seem perpetually never to get published (see discussion in Donegan et al. 2015 Conservacion Colombiana).

    Please see the comments on the Atlapetes nigrifrons thread for links to papers discussing details of the current conservation threats and situation in Perija.

  2. Chris Sharpe says:

    I also agree that saltuensis is a species. As to threats, Perijá is one of the regions undergoing most rapid deforestation in Venezuela. On each visit, there are new roads bulldozed into formerly remote areas and additional forest has disappeared. I have been keeping an eye on satellite imagery too. Many of the colonists in the early 2000s were Colombians, and their arrival may have slowed or halted with the reversal of fortunes of the two countries. Fortunately, none of this recent wave of colonisation reaches the elevation of saltuensis. Indeed there is no easy (road) access to its habitat on the Venezuelan side. The mountainous terrain should afford good protection to Perijá’s montane forests for the moment. However, given the economic circumstances, this could change at any moment. There is next-to-no active management of Sierra de Perijá National Park, the parks institute is severely under-resourced and there is currently little political interest in conserving this region. There are no population data, but (unless there is now deforestation within its elevational range) I doubt that the population has become fragmented.

  3. Chris Sharpe says:

    Further information on deforestation rates in Sierra de Perijá can be found in Hernández-Montilla & Portillo-Quintero (2010). Looking at two large areas, they analyse satellite imagery and find a forest loss of >35% during 1986-2001, an annual rate of 21 km2/year. During the most recent period studied (2002-2007), the rate of deforestation more than doubled to 47 km2/year. They assign “Sierra de Perijá Evergreen Forests” the IUCN category Critically Endangered. There is no information in the study on elevations involved. Undoubtedly, most of this forest loss occurred in the foothills <1500 m, but this may now be pushing higher up and closer to the range of saltuensis. The situation is certainly very worrying.

    Reference
    Hernández-Montilla, M.C. & Portillo-Quintero, C. (2010) Conversión de los bosques
    del norte de la Sierra de Perijá, estado Zulia. Pp. 257-262 in Rodríguez, J.P., Rojas-Suárez, F. & Giraldo Hernández, D. (eds.). Libro Rojo de los Ecosistemas Terrestres de Venezuela. Provita, Shell Venezuela, Lenovo (Venezuela). Caracas, Venezuela.

  4. Aunque considero que muchas de las subespecies de G. rufula deben elevarse al estatus de especie, debido a las diferencias en cuanto su vocalizacion y alopatria entre sus poblaciones.
    es aconsejable tener un poco mas de paciencia hasta que se efectué la publicación de la filogenia de las subespecies de Grallaria rufula que entregara un soporte taxonómico a estos nuevos splits.

    pero considerando en proteger a G. rufula saltuensis, como una unidad poblacional para conservar el estatus de vulnerable, seria adecuado dado que reúne los requisitos solicitados para la categoría VU.

  5. James Westrip (BirdLife) says:

    Based on available information, our preliminary proposal for the 2016 Red List would be to list:

    G. rufula as Least Concern.

    G. saltuensis as Vulnerable under criterion C2a(ii).

    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 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.

  6. Paul Salaman says:

    Two other Perija endemics (Metallura iracunda and Asthenes perijana) are Endangered, but at equal if not perhaps less risk than G. saltuensis.

    G. saltuensis is very much at risk as noted by other reviewers here and absolutely qualifies for Endangered status, owing to a highly restricted area of occupancy (EN B1ab(ii,iii,iv)), plus existing and projected degradation /loss of mature montane cloud forest across its limited area of occupancy, especially limited elevational range. The species habitat is almost entirely fragmented and degraded on the western slope (few locations remain) while the eastern slope is inadequately protected and undergoing habitat loss within/around Perija National Park. The population is crudely estimated to be less than 2,500 individuals with an estimated population decline meeting criteria C2a(i). Considering these issues, plus climate change impacts already being felt in this region (like Sierra Nevada de Santa Marta) G. saltuensis along with a growing number of endemics in Serrania de Perija are facing a dire situation.

  7. James Westrip (BirdLife) says:

    Recommended categorisation to be put forward to IUCN

    Following further review and additional information regarding Minimum Convex Polygon analysis of Extents of Occurrence, the recommended categorisation for G. saltuensis has been changed.

    G. saltuensis is now recommended to be listed as Endangered under criterion B1ab(i,ii,iii,v).

    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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