Archived 2012-2013 topics: Pale-throated Pampa-finch (Embernagra longicauda): downlist to Least Concern?

This discussion was first published  as part of the 2010 Red List update, but remains open for comment to enable reassessment in 2013. Pale-throated Pampa-finch Embernagra longicauda is found on the Serra do Espinhaco of east Brazil (interior central Bahia and Minas Gerais). It was also recently discovered in some isolated ranges in the surrounding region, including Serra da Mombuca, Minas Gerais and Serra do Caparo, Espirito Santo. It could be more widespread in surrounding ranges than previously thought. It is listed as Near Threatened on the IUCN Red List because it was thought to have a restricted range that approaches the threshold for listing as Vulnerable (<20,000 km2) combined with severely fragmented habitat or occurrence at approximately ten or fewer locations and a continuing decline in its habitat, population size or number of locations/sub-populations. However, this species has been mapped by Natureserve/BirdLife International as having an estimated Extent of Occurrence (EOO) of 145,000 km2, hence it does not appear to approach the IUCN thresholds and appears to warrant downlisting to Least Concern. However, if the species has experienced declines over the past three generations (14 years, BirdLife International unpubl. data) approaching 30% it may warrant listing as Near Threatened under the A criterion (population declines). Given its relatively large range size it seems unlikely that this species will have a population approaching 10,000 mature individuals so it would not qualify as threatened or Near Threatened on population size under the C criterion. Comments on the population trends of this species and its proposed downlisting are welcomed. (This discussion was started as part of the 2010 Red List update)

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2 Responses to Archived 2012-2013 topics: Pale-throated Pampa-finch (Embernagra longicauda): downlist to Least Concern?

  1. Recently (18 January 2012; unpublished data), I photographed at the National Park of Serra do Cipó (Minas Gerais), Embernagra longicauda delivering food to a Shiny Cowbird (Molothrus bonariensis) juvenile. This record indicates the brood parasitism as one potential threat for the species. Due to its restricted distribution to the mountaintops, the effects of climate change should also be considered as a potential future threat. Currently, and certainly much more in the future, the mountains are the focus of mining activities concerning various types of rocks. The advance of mining is especially noticeable in the campos rupestres (rocky fields) of the Espinhaço Range (both in Bahia and Minas Gerais), where most of the records of this species occurs. Its naturally fragmented distribution, being restricted to the mountains, should also be seen as a bias in the application of the method used to calculate the EOO.

    Fotografei recentemente (18 de janeiro de 2012; dados não publicados), no Parque Nacional da Serra do Cipó, um jovem de Molothrus bonariensis sendo alimentado por Embernagra longicauda. Este registro indica potencial ameaça do nidoparasitismo na espécie. Devido à sua distribuição restrita às altitudes elevadas de montanhas, os efeitos das alterações climáticas também devem ser considerados como ameaça potencial futura. Atualmente, e certamente muito mais no futuro, as montanhas são alvo de mineração de diversos tipos de rochas. O avanço da mineração é notado especialmente nos campos rupestres da Cadeia do Espinhaço (tanto em Minas Gerais quanto na Bahia), onde se limitam a maior parte dos registros da espécie. Sua distribuição naturalmente fragmentada, por ser restrita às montanhas, também deve ser visto como um viés no emprego do método utilizado para se calcular a EOO.

  2. I agree with the downlist under the C criterion. But we must look with care at these Extent of Occurrence. Due the fact of that the species occur only above 900 m above sea level, on mountains naturally patchily distributed, the area of occurrence can best reflect the range. Building on the map of species known localities (Vasconcelos et al. 2008), we can measure the mountains of the species range, bring us an area of c. 15,000 km2 where possible the species can be found. High density populations can occur in areas with complex groups of habitats available, mainly with trees and shrubs elements which is most selected by the species (Freitas and Rodrigues 2012). On a preserved area in Serra do Cipó (Minas Gerais) we measured 25 individuals/ km2 (Freitas and Rodrigues 2012). High similar densities can also be found in many places along the Espinhaço Range in Minas Gerais and Bahia (GHSF pers. obs.). It is safe to suppose that exist much more than 400 km2 of good quality habitat available in those 15,000 km2 of the range for support more than 10,000 individuals. But in some localities the species can be particularly difficult to find, like in the southernmost population at Serra São José (Minas Gerais) and northernmost population at Morro do Chapéu, Bahia (GHSF pers. obs.). It is also absent on altered areas, like those where occur fire practices for livestock (Freitas and Rodrigues 2012), mining activity, Eucalyptus plantations, among others. Those alterations are known to increase the habitat lost of the campos rupestres habitat (Martinelli 2007). So the mainly concern is about the criterion A. It is necessary the evaluation of how many of those campos rupestres are missing, and how much this lost represent for the Serra Finch populations (in addition with the presumable impact of global warm). Also important is evaluates the degree of evolutionary divergence among the geographic isolated population (e.g. See Chaves et al. 2010), that probably can show divergent structures with different conservations priorities.

    Literature cited:

    Chaves, A.V., M.F. Vasconcelos, A.C. Nascimento, & F.R. Santos. 2010. Phylogeographic patterns and genetic diversity of Polystictus superciliaris
    (Passeriformes: Tyrannidae) in Minas Gerais State. Abstracts of the 25
    th International Ornithological Congress.

    Freitas, G.H.S. & M. Rodrigues (2012) Territory distribution and habitat selection of the Serra Finch (Embernagra longicauda) in Serra do Cipó, Brazil. The Wilson Journal of Ornithology 124(1): In Press.

    Martinelli, G. 2007. Mountain biodiversity in Brazil. Revista Brasileira de Botanica 30:587–597.

    Vasconcelos, M.F., L.E. Lopes, C.G. Machado, & M. Rodrigues. 2008. As aves dos campos rupestres da Cadeia do Espinhaço: diversidade, endemismo e conservação. Megadiversidade 4:221-241.

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