Version 3.1 of the IOC World Bird List incorporates species (and subspecies) that have become Extinct since the early 1500′s (16th Century).
Extinct taxa are marked by the small red dagger (†) after the scientific name, and by “EXT” OR “EXTINCT” in CODE and COMMENT columns.
Since the posting of our initial draft of historically extinct avian taxa with version 2.8, we have received many constructive comments from our users regarding the contents of the list and the application of the criteria that we had adopted to include a form in the listing. We owe many of you debts of thanks in this regard. Special thanks must go to Simon Tonge and Richard Roe whose challenging and insightful comments have induced us to modify our criteria, review our taxonomy and reassess our species limits in order to better document a more complete spectrum of species and subspecies that have been lost in recent centuries.
In the final stages of preparation for the inclusion of extinct taxa into Version 3.1, we have broadened our criteria for inclusion to better reflect the magnitude of the loss of avian diversity in recent centuries. However, our position is to maintain a conservative stance on this and to retain a fairly high threshold for inclusion. As such, we have limited the list to include extinct species and subspecies that meet the following criteria:
1. The taxon became extinct in its geographical range after European contact and, by implication, largely as a consequence of the subsequent anthropogenic effects of hunting pressures, environmental alteration and the introduction of exotic species. It is recognized that mankind has been responsible for the extinction of species from the beginning of our interaction with other life forms, and that this is not a trivial issue. However, extinctions caused by man prior to European contact are beyond the scope of this list. As a consequence, all extinct taxa included in the list disappeared after 1500, the beginning of the era of European overseas exploration.
2. The species is known from physical evidence of its existence, i.e. specimens, skins, skeletal remains or a credible contemporary illustration, painting or drawing that leaves little doubt of the taxonomy and uniqueness of the figured bird (e.g. Tahiti Rail and Tanna Ground Dove, but not “Turdus” ulietensis). Thus, taxa known solely from literary sources without corroborating physical or illustrative evidence, compelling as they may be, are excluded from this list (e.g. Reunion Fody, Guadeloupe Macaw and Reunion Gallinule).
These criteria would eliminate, for example, virtually all of the Caribbean parrots listed by Birdlife International and Tyrberg since they are only known from contemporary accounts of varying quality and are regarded as hypothetical by many authorities. They would also exclude many of the more remotely extinct avifauna from the Pacific and Caribbean islands, which lack contemporary accounts, are known only from skeletal remains and whose dates of extinction relative to European contact are unknown.
In some respects, inclusion or exclusion of forms from a listing of extinct taxa is subjective. Himalayan Quail and Crested Shelduck are included, despite fairly recent rumors of sightings that spark hope that they may still be extant, because most authorities have long regarded them as extinct. On the other hand, Imperial Woodpecker and Bachman’s Warbler are equally likely to be gone forever, but regional authorities have not yet declared them as such.
Even though this list deals with extinct forms, it is far from static. The English names of several listed taxa remain unsettled. We expect that changes will be made to some of these in the future. Similarly, the taxonomy of many of these taxa is in flux. It is expected that in subsequent updates some taxa currently listed as subspecies will be elevated to species. The generic assignments of some groups will be revised and taxonomic sequences readjusted. We will continue to examine our criteria for inclusion. As new physical evidence is discovered, taxa currently excluded from this list because they are only known from contemporary accounts may be candidates for future listing. Sadly, many taxa not included here will be declared extinct in the future as more thorough field coverage fails to uncover evidence of their continued existence. This has happened recently to several Australian taxa. More hopefully, and although it is doubtful, some species currently listed as extinct may be rediscovered as have Kinglet Calyptura and Cebu Flowerpecker in fairly recent years.