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.
Akepa Loxops coccineus is being split into L. coccineus, L. ochraceus and L. wolstenholmei, following the application of criteria set out by Tobias et al. (2010).
The newly defined species L. wolstenholmei was last convincingly reported in 1930 on the Hawaiian island of Oahu (Donaghho 1963) and is generally considered as extinct (Pratt 2005). Therefore, we propose to list the species as Extinct.
L. ochraceus has been known from rainforest and drier koa forest on the Hawaiin island of Maui (Pratt 2016). It was probably once present on all of Maui, but by the end of the 19th Century it was only found on the upper reaches of Haleakala Volcano (Pratt 2016). There were very few records from the 20th Century with the last report in 1988 (Pratt 2016). Surveys in the 1990s failed to find definitive evidence for the presence of this species, but there were some possible audio evidence of this species (Pratt 2010). Therefore, the species may potentially persist. However, if it is still extant it is present in very small numbers (probably <50 individuals). Therefore, it is proposed that this species be listed as Critically Endangered (Possibly Extinct).
Given the taxonomic change has only removed two species that are potentially both extinct there has been little change to the status of the newly defined L. coccineus and so this species would warrant retained the pre-split species’s status of Endangered, and now be listed under criteria B1ab(i,ii,iii,v), although there is debate over whether the species may be in decline (see Freed and Cann 2013, Camp et al. 2014) and so it may only warrant listing under criterion B1ab(i,ii,iii).
Comments are invited on these proposed categories and further information would be welcomed.
Camp, R.J., Pratt, T.K., Gorresen, P.M., Woodworth, B.L. and Jeffrey, J.J. 2014. Hawaiian forest bird trends: using log-linear models to assess long-term trends is supported by model diagnostics and assumptions (reply to Freed and Cann 2013).
Donaghho, W.R. 1963. A Resume of the ‘Extinct’ Hawaiian Species, With Listings of Sight Records and Reports During My Sojourn in the Islands. Elepaio 23: 55–58.
Freed, L.A. and Cann, R.L. 2013. More misleading trend analysis of Hawaiian forest birds. Condor 115: 442-447.
Pratt, D. 2016. Maui Akepa (Loxops ochraceus). 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/61440 on 1 October 2016).
Pratt, H.D. 2005. The Hawaiian Honeycreepers. Oxford University Press.
Pratt, H.D. 2010. Family Drepanididae (Hawaiian Honeycreepers). In Handbook of the Birds of the World Volume 15: Weavers to New World Warblers (J. del Hoyo, A. Elliott and D.A. Christie eds). Lynx Edicions, Barcelona.
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.