"Wisdom begins with putting the right name on a thing"
(Old Chinese Proverb)


The selection of subspecies taxa for any world list is not a  trivial matter.  Although the Peters  Checklist has been the primary source for many subsequent subspecies lists, it  has been nearly twenty-five years since the last volume of the Peters Checklist  was published and many of the earlier volumes in that seminal work date back to  the first half of the last century.  As  such, we felt that we could not use it as our primary source.  Since that time, a wealth of newly published family monographs  and regional handbooks contain species accounts that cover the subspecies of a  significant number of the world’s birds. These have been  invaluable resources for the compilation of this list.  The Handbook  of the Birds of the World, Lynx Ediciones, now completed has carefully selected its own list of the world’s  subspecies and its more recent volumes have been especially useful as sources  of information.  However, we chose to use  the comprehensive and well-annotated third edition of Howard & Moore (2003)  edited by Edward Dickinson and its corrigenda as the baseline for this list.  Where it was necessary to deviate from the treatments in that work and to  incorporate material that had come to light subsequent to its publication, we  gleaned information primarily from appropriate journal articles and from those  sources referred to above.This list should be regarded as a dynamic one that will be subject  to ongoing revisions as new taxa are described, others dismissed, taxa  inadvertently excluded are added and other new taxonomic information becomes  available. Surely, like other lists, this one contains many currently  recognized but questionable subspecies that represent doubtfully discrete  phenotypic types within a cline of forms.   In contrast, many geographically isolated subspecies will, in time, be  regarded to be full, allopatric species.  Recent advances in molecular phylogeny have shown that many  traditionally recognized subspecies do not correlate with the well-defined  clades identified by genetic studies. Lastly, many valid subspecies will  be recognized or discovered in the years ahead. We expect that this list will  be revised regularly as new information becomes available.

The nomenclature used and the authors cited for this list are substantially  aligned with that of Alan Peterson as published on his Zoonomen website .  This aspect of the  project could not have been completed without his enthusiastic cooperation and full  collaboration. While some of these determinations may vary from other  treatments, they all are thoroughly substantiated. We urge interested  colleagues to check the Zoological Citation Notes on the Zoonomen site for any  clarifications.

Our goal is to provide a truly current list of subspecies to  facilitate tracking the population compositions that accompany ongoing  taxonomic revisions and nomenclature at the species level.  Doing so  expands the IOC World List to over 30,000 taxa that will require careful  stewardship.We welcome your participation.

The expansion of the IOC World Bird List  incorporates the feedback we have received from many of our users regarding  errors and inconsistencies of the spelling and content of the subspecies taxa, and  authors and dates of publication. Special acknowledgement must be given to  Colin Jones for the many dedicated hours he has spent collaborating with us in  this regard. Thanks to all of you for your continued interest and invaluable  contributions.

David Donsker April 25, 2012