Archived 2016 topics: BirdLife are recognising Cyornis djampeanus; list as Near Threatened or 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.

BirdLife are recognising the newly defined Cyornis djampeanus.

C. djampeanus, Tanahjampea Blue-flycatcher, is found only the islands of Tanahjampea and Kalao, Indonesia. On Tanahjampea, it is known from closed-canopy forest, and is rarely found in degraded mangroves, if at all (Clement 2016). Its highly restricted range likely encompasses an Extent of Occurrence of less than 5,000km2, pending Minimum Convex Polygon analysis. The global population size has not been directly estimated, but it is has been described as common (Clement 2016) and is suspected to fall in the range of 1,000-2,500 mature individuals, with the population on Tanajampea suspected to be >1,000 mature individuals. This population size estimate fits with population density estimates for closely related species and the assumption that only a proportion of available habitat is inhabited.

The population is inferred to be in decline as a result of continued logging activity on the islands (see Hansen et al. 2013), but the number of locations* where this species is found likely exceeds 10 and the species may not approach the threshold for Vulnerable under criterion B1. We request any further information regarding population size and trend estimates, but in the absence of any further information it is proposed that this species be listed as Near Threatened under criterion C2a(i).

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

*Note that the term ‘location’ defines a geographically or ecologically distinct area in which a single threatening event can rapidly affect all individuals of the taxon present. The size of the location depends on the area covered by the threatening event and may include part of one or many subpopulations. Where a taxon is affected by more than one threatening event, location should be defined by considering the most serious plausible threat (IUCN 2001, 2012).

References:

Clement, P. 2016. Mangrove Blue-flycatcher (Cyornis rufigastra). 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/59096 on 12 October 2016).

Hansen, M. C., P. V. Potapov, R. Moore, M. Hancher, S. A. Turubanova, A. Tyukavina, D. Thau, S. V. Stehman, S. J. Goetz, T. R. Loveland, A. Kommareddy, A. Egorov, L. Chini, C. O. Justice, and J. R. G. Townshend. 2013. High-Resolution Global Maps of 21st-Century Forest Cover Change. Science 342: 850–53. Data available on-line from: http://earthenginepartners.appspot.com/science-2013-global-forest. Accessed through Global Forest Watch on 10th October 2016. www.globalforestwatch.org

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.

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: BirdLife are recognising Cyornis djampeanus; list as Near Threatened or Vulnerable?

  1. James Eaton says:

    The species is quite common throughout primary and secondary forest, and even found in heavily degraded areas of bamboo, and even nipa palm swamps.

  2. James Westrip (BirdLife) says:

    Based on available information, our preliminary proposal for the 2016 Red List would be to adopt the proposed classification 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.

  3. Rob Martin (BirdLife International) says:

    Comments have been received from Burung Indonesia (in litt. 2016) supporting the listing of this species as Near Threatened.

Comments are closed.