In 1994, Ridgely and Tudor published the second volume of their acclaimed Birds of South America series (The Suboscine Passerines) after a 5-year hiatus following publication of the first volume. Now, 15 years later, we are presented with a Field Guide to the Songbirds of South America, a condensation (shorter species accounts) and “expansion” (more species illustrated) of their original work into a portable guide. Since the publication of Birds of South America, a number of single-country field guides have been published (or revised), including authoritative works covering Peru, Ecuador, Venezuela, and Chile, as well as more regional guides covering areas such as southern South America. For the first time, a comprehensive guide to the Passerines that covers all of South America is now available. To assess the usefulness of such a guide, one must consider the target audience for which the book was published. Will (or should) an avid birder or ornithologist carry this guide in the field? Clearly this is an attractive book. Given that it combines Tudor's artwork, which is often considered among the best, with Ridgely's extensive knowledge of South American birds, this guide has the potential to be a very important treatise.

The book is organized so that the 121 color plates (expanded from the original 83 plates) are presented in the front, accompanied by facing pages containing range maps, followed by 420 pages of species accounts. The text states that full accounts are presented for 1,981 species, although I counted only 1,916. Of these, the ranges of 1,896 species are represented on the maps, but only 1,555 species are actually illustrated, leaving somewhere between 341 and 426 (if I counted correctly) species that are not illustrated. I must say that I was looking forward to the publication of this guide but find the high percentage (∼20%) of nonillustrated species disappointing. Admittedly, it must have been a daunting task to produce a guide that covers nearly 2,000 species, but one must question the decision to not illustrate such a large number of species. The authors' justification is that many of the species left out are “similar” to others that are illustrated or have “limited geographical ranges” or are “certain boreal migrants.” I would contend that many of the species that are not illustrated would have been most useful to the user of this guide to have illustrated. Birders use field guides to separate similar-looking species and to identify the local specialties—two groups represented often in the omission list. Regardless of the reasons, anyone using this guide is bound to be frustrated by these omissions.

Perhaps even more frustrating for the birder will be the taxonomic treatment and nomenclature of South American bird species. While I agree that the taxonomy of South American birds represents a fluid subject (and that perhaps no “correct” treatment exists for many species), I find the authors' disregard of the South America Check-list Committee (SACC), which is sanctioned by the AOU, disappointing. Instead they basically follow the International Ornithological Congress's (IOC) World Bird List. It is somewhat amusing to look up a taxonomically controversial species on the IOC list, only to find out that the IOC accepts it as a “good” species and then cites Birds of Ecuador by Ridgely and Greenfield. Unfortunately, this is an example of circular reasoning. A difference in philosophy as to what constitutes adequate documentation required to lump or split species, and perhaps a difference in actual species definition between the authors (as an extension of the IOC) and the SACC, has the potential to create great confusion for the average user of this guide. From a practical standpoint, it would be nice if there were a more universally accepted, consistent ordering of species—the ordering in this book is often radically different from the SACC order. Given that most “listing” software and publications (such as Clements's Birds of the World: A Checklist) now follow the SACC, the user is certain to be frustrated by the species order used in this guide. In a similar fashion, the authors, in my opinion, take too many liberties with regard to presenting different (from the SACC) common English names of species, many of which were made up or changed simply out of personal preference. As a bird tour leader, I know this will confuse the average potential user of this guide. There are 16 pages on “Notes on Taxonomy and English Names” at the end of the book, where the authors justify many of their decisions (but still disregarding the decisions of the SACC—in fact never mentioning the committee). One complaint about this section is that the “footnotes” are not numbered, which forces the user to search through text to find a particular species. A numbered system would have been much more concise and easier on the eyes (and brain).

The maps are necessarily small so as to fit on the pages that face the respective plates. They present a good “general” overall range for each species, and the authors claim to have incorporated relatively new information (since 1994, but only through 2006). At least there is a map for most of the nonillustrated species, although nothing is presented on the plates (or maps) to indicate how one of these mapped (but not illustrated) species is “very similar” to another species on the plate. One has to dive into the species accounts at the rear of the book to find this information. As a user of field guides on birding tours, on which some participants have been known to cut out the plates and not carry the text portion of guides (not that I condone this practice), I predict a lack of satisfaction with the design of this guide. Users want a field guide that includes all the species and presents them in a compact format. I will say that the species accounts present a wealth of information in a condensed format, combining plumage characteristics, range, habitat, behavior, and vocalizations, such that the user should find the accounts quite useful for bird identification. This is a clear testament to Ridgely's extensive knowledge of South American birds.

The real questions are, who was this book designed for, who is going to use this book, and is it worth owning? In my opinion, the book was clearly created for a birder visiting South America. The concept of a comprehensive guide for an entire continent, particularly one as complex as South America, seems like a throwback to a different era, when regional and country guides did not exist. In the early 1980s, I would have died for such a guide. Today, though, there are numerous excellent country guides (including Birds of Ecuador) that, I would contend, reduce the relevance of such a continent-wide guide. Today, this guide may be quite useful in a few countries that currently lack a good guide (such as Bolivia), but be forewarned that close to 20% of the passerines, as well as 100% of the nonpasserines, will be missing. The authors had the opportunity to rectify this major complaint against their earlier work, but for some reason chose not to. As a collector of books on South American birds, I would say that it is still worthwhile owning this book, particularly as an additional, quick reference that includes more of Tudor's excellent art work (although it is quite expensive), but from my experience, when visiting a country (such as Peru, Colombia, Ecuador, etc.), one will desire a field guide that has everything included—particularly in this day and age of weight restrictions on air flights. This is an attractive book with a wealth of (repackaged) information in a condensed form, but it has its limitations as a practical field guide.