Cipo Canastero (Asthenes luizae): revise global status?

BirdLife species factsheet for Cipo Canastero

Cipo Canastero (Asthenes luizae) occurs in few localities in Minas Gerais, Brazil (Espinhaço mountain range and Diamantina plateau, Campina do Bananal, and further north in Monte Azul; Chaves Cordeiro et al. 1998, Vasconcelos et al. 2002, Vasconcelos and D’Angelo Neto 2007). The species was only discovered in 1985. The population size is not known; estimates based on an assumed 10,000 km2 of habitat and a density of 10 individuals/km2 report a number of 100,000 individuals (M. F. de Vasconcelos in litt. 2007). However, as this number might be an overestimate (L. E. Lopes in litt. 2009), the population is tentatively placed in the band 50,000-99,999 individuals in total (BirdLife International 2018). Cipo Canastero is a mainly terrestrial species inhabiting campo rupestre, isolated rocky outcrops with dry, bushy vegetation. It ranges from 1,000 to 2,000 m and prefers steep, well vegetated slopes. 

Its small geographic range and the inherent insular nature of suitable habitat make the species vulnerable to threats like grazing and burning of its habitat (Remsen and de Juana 2018). However, due to the remoteness and overall low suitability for agriculture of campo rupestre, Cipo Canastero is assumed to be fairly safe. Brood parasitism by the recently introduced Shiny Cowbird (Molothrus bonariensis) might constitute a potential risk to the species, but reports so far are scarce (L. E. Lopes in litt. 2009). Overall, the population is suspected to be stable, with at most local declines.  

Currently, Cipo Canastero is listed as Near Threatened under Criterion B1ab(iii) (BirdLife International 2018). However, this is no longer tenable because this was based on an Extent of Occurrence (EOO) value calculated as the ‘area of mapped range’. This is no longer appropriate, and the EOO should be calculated using a Minimum Convex Polygon (see IUCN 2001, 2012, Joppa et al. 2016), as EOO is a measure of the spatial spread of areas occupied by a species, not the actual area it occupies. After re-calculating the EOO for Cipo Canastero, the species appears to warrant a change in Red List status. Therefore, we present here our reassessment against all criteria for the species.

Criterion A – Although Cipo Canastero may be undergoing some local declines caused by habitat degradation and potentially low levels of brood parasitism, the species is suspected to be overall stable. Therefore, Cipo Canastero may be listed as Least Concern under Criterion A.

Criterion B – The newly calculated Extent of Occurrence (EOO) for this species is 41,200 km2. This does not meet the threshold for Vulnerable (EOO < 20,000 km2). Therefore, Cipo Canstero may be listed as Least Concern under Criterion B1. The Area of Occupancy (AOO) has not been calculated and thus the species cannot be assessed against Criterion B2.

Criterion C – The population size has tentatively been placed in the band 50,000-99,999 individuals in total (BirdLife International 2018), which roughly equates to 30,000-70,000 mature individuals. This is too large to approach the threshold for Vulnerable (10,000 mature individuals). Therefore, Cipo Canastero may be listed as Least Concern under Criterion C.

Criterion D – The population size is too large to approach the threshold for Vulnerable (1,000 mature individuals). Therefore, Cipo Canastero may be listed as Least Concern under Criterion D.

Criterion E – To the best of our knowledge no quantitative analysis of extinction risk has been conducted for this species. Therefore, it cannot be assessed against this criterion.

Therefore, it is proposed that Cipo Canastero (Asthenes luizae) be listed as Least Concern. We welcome any comments on this proposed listing.

Please note that this topic is not designed to be a general discussion about the ecology of the species, rather a discussion of its Red List status. Therefore, please make sure your comments are relevant to the discussion outlined in the topic.

An information booklet on the Red List Categories and Criteria can be downloaded here and the Red List Criteria Summary Sheet can be downloaded here. Detailed guidance on IUCN Red List terms and definitions and the application of the Red List Categories and Criteria can be downloaded here.

References

BirdLife International. 2018. Species factsheet: Asthenes luizae. http://www.birdlife.org (Accessed 21 December 2018).

Chaves Cordeiro, P. H.; de Melo, T. A., Jr.; Vasconcelos, M. F. de. 1998. A range extension for Cipó Canastero Asthenes luizae in Brazil. Cotinga 10: 64-65.

IUCN. 2001. IUCN Red List Categories and Criteria: Version 3.1. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, U.K.

IUCN. 2012. IUCN Red List Categories and Criteria: Version 3.1. Second edition. IUCN Species Survival Commission. IUCN, Gland, Switzerland and Cambridge, U.K. www.iucnredlist.org/technical-documents/categories-and-criteria.

Joppa, L. N.; Butchart, S. H. M.; Hoffmann, M.; Bachman, S. P.; Akçakaya, H. R.; Moat, J. F.; Böhm, M.; Holland, R. A.; Newton, A.; Polidoro, B.; Hughes, A. 2016. Impact of alternative metrics on estimates of extent of occurrence for extinction risk assessment. Conservation Biology 30: 362-370.

Remsen, J.V., Jr; de Juana, E. 2018. Cipo Canastero (Asthenes luizae). 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, Spain. https://www.hbw.com/node/56508 (Accessed 21 December 2018).

Vasconcelos, M. F. de; D’Angelo Neto, S. 2007. Padrões de distribuição e conservação da avifauna na região central da Cadeia do Espinhaço e áreas adjacentes, Minas Gerais, Brasil. Cotinga 28: 27-44.

Vasconcelos, M. F. de; D’Angelo Neto, S.; Rodrigues, M. 2002. A range extension for the Cipó Canastero Asthenes luizae and the consequences for its conservation status. Bulletin of the British Ornithologists’ Club 122: 7-10.

This entry was posted in Americas, South America and tagged , . Bookmark the permalink.

2 Responses to Cipo Canastero (Asthenes luizae): revise global status?

  1. Red List Team (BirdLife International) says:

    Preliminary proposal
    Based on available information, our preliminary proposal for the 2019 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 in mid-July, 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 2019 Red List categories will be published on the BirdLife and IUCN websites in December, following further checking of information relevant to the assessments by both BirdLife and IUCN.

  2. Red List Team (BirdLife International) says:

    Recommended categorisations to be put forward to IUCN
    Based on available information, our proposal for the 2019 Red List is to pend the decision on this species and keep the discussion open until 2020, while leaving the current Red List category unchanged in the 2019 update.
    Final 2019 Red List categories will be published on the BirdLife and IUCN websites in December, following further checking of information relevant to the assessments by both BirdLife and IUCN.

Leave a Reply

You have to agree to the comment policy.

This site uses Akismet to reduce spam. Learn how your comment data is processed.