Archived 2010-2011 topics: Diamantina Tapaculo (Scytalopus diamantinensis): newly described and threatened?

Diamantina Tapaculo Scytalopus diamantinensis has been described from the Chapada Diamantina, Bahia State, Brazil (Bornschein et al. 2007) and is now recognised by BirdLife in line with SACC (2008).

Bornschein et al. (2007) present nine points (tape recorded individuals or specimens) loosely restricted to four localities within the Chapada Diamantina, separated by up to 150 km. All records come from ‘campo rupestre’ vegetation, a mosaic of plant communities found above 800 m in the Serra do Espinhaço, of which the Chapada Diamantina is a part (Bornschein et al. 2007). This habitat continues to the south into Minas Gerais. Other species of the campo rupestre are currently classified as Near Threatened (except Cipó Canastero whose current status as Vulnerable but is under review for downlisting to NT), almost meeting criterion B1 because the total area of campo rupestre is estimated at just c. 10,000 km2. However, because Scytalopus diamantinensis is currently known from just four locations within a smaller range, Bornschein et al. (2007) recommend that it be classified as Vulnerable under B1a+b with an estimated Extent of Occurrence of less than 20,000 km2 (but more than 5,000 km2) at fewer than ten locations and a continuing decline in the extent and quality of available habitat. If this classification is agreed, it is worth pointing out that further research may reveal the species to be more widespread and common, and that its habitat is relatively stable; upland habitat is unlikely to be being rapidly encroached. If treated here as Vulnerable, further work in the future may lead to a revision of its status.

Comments on the species’s likely true distribution, and threats to its habitat are welcomed to inform this assessment.

Bornschein, M. R., Maurício, G. N., Lopes, R. B., Mata, H. and Bonatto, S. L. (2007) Diamantina Tapaculo, a new Scytalopus endemic to the Chapada Diamantina, northeastern Brazil (Passeriformes: Rhinocryptidae). Revista Brasileira de Ornitologia 15(2): 151-174.

(This discussion was started as part of the 2010 Red List update)

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2 Responses to Archived 2010-2011 topics: Diamantina Tapaculo (Scytalopus diamantinensis): newly described and threatened?

  1. Andy Symes says:

    Comments received as part of 2010 update:
    Ricardo Belmonte-Lopes (Mater Natura – Instituto de Estudos Ambientais) and Marcos Ricardo Bornschein (July 2009):

    Different from what is written above and as pointed by BORNSCHEIN et al. (2007), the species do not occurs in “campo rupestre” (being comparable to ‘campo rupestre’ endemic species because of its pattern of occurrence) but in forest areas and secondary areas that were once forest (“capoeiras”), with Scytalopus diamantinensis representing “the only forest bird restricted to the Serra do Espinhaço”. Here can be useful a comment on the geological nomenclature: Serra do Espinhaço is a mountain range that starts at south of Minas Gerais state and ranges through almost all this state, ending in the south of Bahia state. It comprises different and nowadays somewhat distinct geological formations given to different geological events, having different names for its sectors that are somewhat disconnected (e.g. Serra do Cipó, Chapada Diamantina, etc).

    About habitat in Minas Gerais, also, as pointed by BORNSCHEIN et al. 2007, is worth of note that the populations of Scytalopus occurring in the Central and Southern Serra do Espinhaço actually represent a new species under description by colleagues (Scytalopus sp. nov., see BORNSCHEIN et al. 2007), and that is this species and not Scytalopus diamantinensis that occurs in “campo rupestre”. Also, the higher grounds of Chapada Diamantina were S. diamantinensis occurs are separated from the southern part of Serra do Espinhaço (where Scytalopus sp. nov. occurs) by lower areas (300-500 m that nowadays prevents its dispersion due lacking habitat.

    Chapada Diamantina itself comprises about 38.000 km2 of different habitat kinds like “cerrado”, “cerrado rupestre”, “campo rupestre”, “caatinga” and also forest remains that occurs mainly at its eastern slopes, higher areas and some deep river valleys. Scytalopus diamantinensis apparently is restricted to these forest areas and some of its secondary formations (e.g. “capoeiras”). A preliminary estimative, based on the altitude of occurrence a.s.l, indicates that S. diamantinensis have an EOO of 9.750 km2, but is possible that, if Chapada Diamantina forest areas were accurately measured, the species will show an EOO even smaller, maybe meeting the criteria B1 (Extent of occurrence estimated to be less than 5000 km2) for endangered species.

    In a second expedition to Chapada Diamantina, Bahia, M.R.B. and R.B-L failed to found the specie at the northernmost previous know locality, at north of Bonito (RAPOSO et al. 2006), but found additional localities surrounding the previous localities around Ibicoara. This additional fieldwork reinforced the initial idea that the specie is under extinction threat, since it didn’t change its EOO.

    As Scytalopus diamantinensis occurs only in forests (and secondary areas know as “capoeiras”), its habitat is being continuously reduced and fragmented. Until now, we identified three main threats for its habitat:
    – Conversion on farmlands (mainly coffee and banana) (sometimes with governmental loans);
    – Vegetal coal production from native forests (residential and industrial scale); and
    – Frequent burning.

    We believe that further fieldworks will certainly bring to light new records and localities of Scytalopus diamantinensis, but in our opinion, is very difficult that this new localities change its EOO and consequently, its allocation in criteria B1 for vulnerable species.

  2. Andy Symes says:

    operations (October 2009):
    The current BirdLife range map for the species is attached: it may require some modification and comments on its accuracy are welcome. Note that the range on the attached map equates to an EOO of 21,157 km2, which is significantly larger than that suggested by Ricardo Belmonte-Lopes above.

    Details of point localities for the new locations mentioned above would also be very much appreciated.

    Scytalopus diamantensis BirdLife.jpg

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