Birds of the World: A Checklist (5th edition).—James F. Clements. 2000. Ibis Publishing Co., 3420 Freda's Hill Road, Vista, California 92084-7466. xx + 867 pp. ISBN 0-934797-16-1. Cloth, $39.95 + $8.00 s & h.—This 5th edition is a major revision of the 4th edition (reviewed in Auk, 109:403–404). Along with the expected newly described or taxonomically revised species, the basic classification has been changed from previous editions to mirror that of the Handbook of the Birds of the World series (Lynx Edicions, Barcelona, 1992 ff.), sponsored by BirdLife International. Handbook of the Birds of the World's base sequence is essentially that of Morony, Bock, and Farrand (Reference List of the Birds of the World, 1975, American Museum of Natural History). In Handbook of the Birds of the World, Morony, Bock, and Farrand has been modified to reflect widely accepted newer treatments of avian relationships and more liberal species limits while still basically adhering to the Biological Species Concept. Although no exact number is given, Birds of the World is said to list ∼9,800 species. It is designated as the “official world checklist” of the American Birding Association.
Added to this edition of Birds of the World are subspecies (scientific names and approximate ranges) of polytypic species; a list of extinct species; a gazetteer; lists of countries sorted by number of recorded species and (separately) by number of endemic species in each; and an English-name index. English names generally follow American orthographic conventions and are largely based on Handbook of the Birds of the World, when possible, or other widely used references which mostly are listed in the bibliography. The main list has been spread out considerably, so that the volume now is particularly attractive and easy to use. Outright lapses seem relatively few but can readily be found, for example, interchanged ranges for the two subspecies of Aechmophorus clarkii, and locations missing from the gazetteer for the stated range of Calyptophilus f. frugivorus. Birds of the World weighs over 2 kg and is approximately the same size and bulk as Distribution and Taxonomy of Birds of the World by Sibley and Monroe (Yale University Press, 1990). Unlike Sibley and Monroe, however, it contains virtually no explanatory text and seems primarily intended to serve as a standardized tick-list for globe-trotting birders.
Any undertaking of this nature is an effort to compile and present detailed ornithological (primarily avifaunal) information to a largely nonprofessional audience. These are contentious times in avian taxonomy and nomenclature. By selecting the lavishly descriptive, intellectually robust, and widely acclaimed Handbook of the Birds of the World as a flagship, users potentially are offered their best contemporary opportunity to view the world's birdlife in a simplified manner but through professional eyes. There are problems, however. One of the foremost results from the fact that only about a third of the world's bird species, through the Apodiformes in Handbook of the Birds of the World's sequence, had been covered when this edition of Birds of the World was published. For the remaining two-thirds, this edition is based largely on the increasingly outdated Peters' Check-list of Birds of the World series (Harvard University Press, 1931, ff.), and popular modern family monographs or handbooks where available, sequenced at the family level and above by an “in litt.” from Handbook of the Birds of the World's editors. This higher-level sequencing convention results in some strange and eye-catching placements, such as the kinglets between bulbuls and leafbirds, or the vireos between whydahs and fringillids. Because it has for some well-documented situations in the volumes already published, the Morony, Bock, and Farrand sequence is likely to be updated by the Handbook of the Birds of the World team as future volumes are prepared, based upon then-current, widely accepted criteria. Meanwhile, it would have seemed wiser for Birds of the World to follow some published hypothesis of relationships, such as that used by Morony, Bock, and Farrand.
Another disappointment for me is the general absence of citations for virtually all deviations from the underlying reference work(s) for each family. For example, Puffinus atrodorsalis (Shirihai, Sinclair and Colston, Bulletin of the British Ornithologists' Club 115:75–87) is added to Birds of the World without reference or explanation. Ninox ios (Rasmussen, 1999, Wilson Bulletin 111:457–464) also is added to Birds of the World with a reference in the bibliography. Sula granti (Pitman and Jehl, Wilson Bulletin 110:155–170), on the other hand, is omitted from Birds of the World even though it was described a year earlier in the same journal as N. ios. What are the criteria for inclusion or exclusion of newly described species? Similar unevenness applies to taxonomic revisions, subspecies, detailed sequence, and choices of names. The Scaly-breasted Thrasher (Margarops fuscus) is treated as a monotypic species in the genus Allenia in volume 9 of Check-list of Birds of the World, the only reference mentioned for the Mimidae, but is considered polytypic in the genus Margarops in Birds of the World. Why? The usefulness of Birds of the World would have been greatly enhanced if all changes, inclusions, exclusions, rearrangements, and renaming at either the scientific or English-name level for all deviations from the given references were documented, even if the citation or footnote were simply “author's opinion/preference.”
The relationship between Birds of the World and The American Ornithologists' Union Check-List of North American Birds (American Ornithologists' Union, 7th ed., 1998) also is less well documented than I would wish. Although AOU's Checklist is hardly sacrosanct, it has served the ornithological and birding communities well as the foundation of North American regional taxonomy and nomenclature for more than a century. Explanations of deviations from it would avoid confusing an American audience, particularly those members not fully conversant with all the literature. Examples of unfamiliar treatments can readily be found, such as the sequence and species limits within the genera Glaucidium and to a lesser extent Otus.
American birders, who probably are the primary intended audience, mostly should be pleased with the appearance and basic simplicity of Birds of the World. Those with a more scholarly interest in avian speciation and relationships, however, may prefer to wait. When Handbook of the Birds of the World is completed and back-updated, Birds of the World hopefully would be revised, either to conform with Handbook of the Birds of the World, or giving references to relevant literature for all changes. Only then would it provide the chain of evidence distinguishing science from revelation. In the meantime, for anyone who can work with its simplicity, Birds of the World is not only useful, but also very much a bargain.