Open Access
How to translate text using browser tools
1 January 2011 Book Reviews
R. Todd Engstrom, Robert E. Gill, Daniel W. Anderson, Clait Braun, Eli S. Bridge, William S. Clark, Bruce Eichhorst, Jules Evens, David C. Evers, Floyd E. Hayes, Alvaro Jaramillo, Ian L. Jones, Kenneth D. Richkus
Author Affiliations +

The following critiques express the opinions of the individual evaluators regarding the strengths, weaknesses, and value of the books they review. As such, the appraisals are subjective assessments and do not necessarily reflect the opinions of the editors or any official policy of the American Ornithologists' Union.

Pete Pyle has done it—found that 25th hour in the day that so many of us covet. What else could explain his ability to research, synthesize, and present the breadth of information treated in the 836 pages of Part II of his landmark compendium on bird identification? And all during only a 6-year period! Before we elevate Pyle to some superhuman status, we should comment that he had help, and he freely acknowledges the many contributions made by others. Still, anyone who plays at the game of scientific writing and publishing can only sit in awe of what it took for Pyle and colleagues to produce this two-volume set.

Part II has been available for about 2 years and has been the subject of several book reviews in mainstream ornithological journals (e.g., Bridge 2009, Gustafson 2009, Hipfner 2009, Lloyd-Evans 2009). Each reviewer assesses the book's format and scope, its match with the intended audience, and its strengths and weaknesses. In Part I, Pyle (1997) addressed Passeriformes and closely related orders; Part II deals with the rest of the North American avifauna and treats 310 species and 276 subspecies of waterbirds, gallinaceous birds, and diurnal birds of prey. Although this two-volume work is called an “identification guide,” it (and particularly Part II) will serve as such only if you have a bird in hand and your questions concern the bird's age and sex as determined primarily by molt, plumage, and measurements. The introduction to Part II is long (46 pages); in addition to setting the stage for what follows, it provides a primer on molt terminology and strategies and a glossary of the myriad terms and abbreviations used throughout the species accounts. (Users of this guide must understand these terms or risk becoming lost in the alphabet soup before them.) Each account includes a description of the species' distinguishing features, its geographic variations if applicable, a detailed description of molt (by type, season, sex, and age), sex-related differences in plumage and measurements, hybrids reported, and references. Both supporting graphic (black-and-white line drawings) and tabular material frequently accompany the species accounts. The focus of each account is a bar graph that uses the aforementioned metrics to allow the user to reliably identify the age and sex of birds throughout seasonal periods. Previous reviewers have consistently awarded Pyle's new volume with high marks, particularly as a reference for those who work with birds in the hand. So, why another review in these pages?

First, in this day and age it is the rare individual who can critically assess a body of material that covers almost 600 avian taxa. Thus, at the suggestion of Todd Engstrom, a team of taxonomic specialists was assembled to offer an order-by-order review of the book's contents (in essence, 12 reviews by taxonomic group). Viewed another way, we were charged with delving several layers deeper than a single reviewer can for a book of this size, scope, and complexity. Second, the book has already become a major reference. As such, and as the author has anticipated, revisions will occur. Indeed, Pyle considers this a “first draft, for all of us to work on and improve.” Our charge as taxonomic specialists was to make a first cut at identifying needed revisions and consider ways to incorporate them in subsequent editions of the book.

We used an admittedly nonscientific questionnaire to create this review. The questionnaire was developed by R.E.G. with concurrence from Engstrom, and R.E.G. is responsible for any biases, overt or otherwise. The questionnaire consisted of two parts, the first a set of 3 multiple-choice questions on general aspects of the book and the second a set of 12 questions that evaluate specific aspects common among the taxonomic groups. The block of 12 questions was divided equally among multiple-choice, yes-or-no, and narrative responses. We list each question below, with the most frequent response(s) among the 12 reviewers in bold, tally the responses, and summarize the reviewers' comments.


  1. Realizing that professional experience plays a huge role in this, do you think that effective use of this book requires (a) no prior skills in identification; (b) some training in field identification; (c) advanced skills in field identification; (d) advanced skills, including pterylography and molt; or (e) extensive training and experience with pterylography, molt, and meristics?

    Results.—(a) 0, (b) 1, (c) 2, (d) 6, (e) 3.

    Comments.—An understanding of molt and plumage is almost mandatory for use of this book as intended by the author.

  2. Who will find the book most useful, (a) beginning birders, (b) intermediate birders, (c) advanced birders, (d) bird banders, (e) researchers handling live birds, (f) people working with museum material, (g) those with a general interest in ornithology, (h) resource-agency personnel who handle birds, or (i) others (who)? Please identify as many as you think are appropriate.

    Results.—(a) 0, (b) 0, (c) 7, (d) 10, (e) 11, (f) 9, (g) 1, (h) 5, (i) 0. Comments.—The common theme is that the book will be useful to those working with birds in the hand.

  3. For the target audience, does the book meet its stated aim? (a) No; (b) Somewhat, overall; (c) Yes, but variably by taxonomic group; or (d) Yes, overall.

    Results.—(a) 0, (b) 2, (c) 2, (d) 8.

    Comments.—Part II will be well received by its intended audience of hands-on users.


  1. For your taxonomic group, did you find that the treatment (a) was incomplete, (b) provided a compendium of mostly existing information, (c) offered new interpretations of mostly existing information, or (d) offered considerable new information and reevaluation of existing information?

    Results.—(a) 1, (b) 2, (c) 4, (d) 7.

    Comments.—Multiple answers were given for the Pelicaniformes (c and d) and Galliformes (a and b). When and how extensively museum specimens were consulted should have been stated (Procellariiformes). This provides the first synthesis of molt, aging, and sexing information for North American grebes (Podicipediformes). Despite several recent papers by Pyle (and S. Howell), Part II still offers new and useful interpretations and clarifications of gull molts (Laridae). The only species or subspecies accounts that were lacking in recent literature were the Cackling Goose and Canada Goose accounts and those for the assorted subspecies (Anseriformes).

  2. For your taxonomic group, did you find that the supporting references (a) were incomplete or outdated; (b) included the most relevant published information; (c) included current scientific literature and some useful gray literature, the latter with adequate attribution; or (d) were comprehensive in all aspects? Please try to give an overall assessment for your group, but elaborate if the level of treatment is disparate by species and family.

    Results.—(a) 1, (b) 6, (c) 0, (d) 5.

    Comments.—An incomplete suite of measurements prevented accurate comparisons for some species (Podicipediformes). Only 5 of 7 subspecies of Canada Geese that regularly occur in North America were treated (Anseriformes). Pertinent Old World literature (especially Russian) was obviously overlooked (Charadrii). Pyle missed nothing in the review paper from 2006 (Procellariiformes). The grebe treatments were comprehensive in all aspects (Podicipediformes). Even very recent literature from relatively obscure journals was included (Ciconiiformes).

  3. For your taxonomic section, would you describe the tables and figures used in support of the text as (a) inadequate, overall; (b) adequate for the points supported; (c) adequate, but some points could have benefited from additional graphic support; (d) appropriate throughout; or (e) inappropriate in that some points did not need graphic support or could have been supported with a little additional narrative?

    Results.ï—(a) 0, (b) 1, (c) 8, (d) 3.

    Comments.—The same figure is often cited for multiple species when there are (usually minor) morphological differences among species (Procellariiformes). The information presented was generally adequate but a small amount was not correct and no information on body masses was presented (Falconiformes). A few measurements used by researchers in the Old World should have been considered (for stronger comparison), given that shorebird biologists universally use the same suite of measurements (Charadrii). Images of whole birds would be useful (Laridae and Stercorariidae). Molt section could benefit from more graphic support (Anseriformes).

  4. Did use of gray-scale drawings clearly support the points being made in your section? Yes or No.

    Results.—Yes: 8, No: 4.

    Comments.—One reviewer thought that color throughout would be better; others thought that color was needed to depict “subtle plumage differences” (Procellariiformes) and soft-part differences (Ciconiiformes); three indicated that higher-quality (more detailed) illustrations were needed (Gruiformes, Charadrii, Alcidae).

  5. Each species account follows a set format. Would you change this format? Yes or No. If yes, please elaborate.

    Results.—Yes: 0, No: 12.

    Comments.—Numerous qualifying statements were offered, including “bit awkward,” “cumbersome at times,” “quite condensed,” “repetitive format helpful,” “easy to compare species,” “quite good.” Use of italics to emphasize important points was suggested.

  6. The book makes extensive use of abbreviations and acronyms, largely to accommodate the sheer volume of material covered. Is this something the user simply needs to accept? Yes or No. If No, please suggest other approaches or modifications.

    Results.—Yes: 10, No: 2.

    Comments.—Most reviewers were resigned to the use of abbreviations and acronyms and argued that not using them would add undue length to an already hefty volume. For Procellariiformes and Gruiformes, the use of acronyms was misleading in places. Inclusion of a bookmark-sized card summarizing acronyms was suggested.

  7. How would you characterize the degree, type, and number of errors in your section: (a) none that I found; (b) minor, involving mostly typos and formatting, and few in number; (c) numerous and misleading to the user, involving mislabeled figures, figure components, formatting, and symbols; or (d) numerous and serious, involving misinterpretation of information or omission of readily available data or references?

    Results.—(a) 3, (b) 9, (c) 0, (d) 0.

    Comments.—Most errors were typographical and should have been corrected during copyediting. The Charadrii and Galliformes sections had more than their share.

  8. In Part I, a photographic companion (Froehlich 2003) was published (hard to find and out of print) that presented photographs of feathers and wings to help supplement the descriptions of plumages and molts. Would similar photographic documentation—either in the book, online, or as published supplemental material—help support the information presented in the order you reviewed? Yes or No. Please elaborate if you care to.

    Results.—Yes: 12, No: 0.

    Comments.—Most reviewers were emphatic that the book would benefit from color images that were made available either online or through references to images published elsewhere. Several reviewers thought that color images were needed to highlight differences in eye color, bill color, and other soft parts, and to provide examples of feather wear. Several also agreed that if color images were not used or referenced, the book should include a plate providing a color palette as a reference for the author's written descriptions of colors.

  9. Part II contains 836 pages. Do you see any utility in physically breaking it up to make it more usable? Yes or No. If Yes, please offer suggestions if you like.

    Results.—Yes: 7, No: 4 (one reviewer did not respond).

    Comments.—Suggestions for breaking the book up included online PDFs of each section, a large formal ring-bound version, and sections being made available online through the publisher. Reasons against breaking it up included keeping all the material available in one place, the impracticality of breaking it up, and the comment that fewer volumes are actually easier to use.

  10. The amount of technical detail contained in Part II (much of it new and not fully evaluated) will ensure a constant stream of revisions over the next several years. Indeed, the author openly considers this a work in progress. In what ways might revisions best be accomplished? For example, should the electronic errata be structured to accommodate more detailed revisions? Please provide a short narrative of any ideas you may have.

    Comments.—Don't change (2); let author publish a revised edition (1); establish an interactive Web/Wiki site where errata/revisions can be posted/downloaded by users (4); create a Wild with author as Wild-Master (1); offer a better way than via the publisher (1); create a webpage with PDF downloads of revised sections or species accounts (2); post supplements through the Bird Banding Manual (1).

  11. Taxonomy/subspecies/geographic variation. [I hear a collective scream of “don't go there.”] The AOU has not updated taxonomy at the subspecies level since 1957 (AOU 1957; but see Winker and Haig 2010). In Part II, Pyle treats 310 species and 276 subspecies. Pyle, like many taxonomists, has his own ideas of organization and uses Part II to make “taxonomic recommendations to standardize recognition of morphological subspecies,” particularly “justifications for synonymization” (see pp. 37–39). Please also keep in mind that molecular systematics—touched on lightly by Pyle— has shown considerable “gray” areas in phenotypic taxonomy. If applicable to your order, are you comfortable with what Pyle has presented? Yes or No. Please provide a brief narrative or examples of issues you find arguable.

    Results.—Yes: 12, No: 0

    Comments.—“Barely comfortable” (Galliformes).

  12. What, if anything, would you suggest be changed in a revision of Part II? Please try to present suggestions as bulleted statements or a short narrative if you think that some level of explanation or justification is warranted. You can reiterate responses to previous questions or throw out new ideas.

    Comments.—R.E.G. received five full pages of narrative from the 12 reviewers, portions of which have been incorporated in the “Comments” sections above. The comments ranged from very general, regarding issues of format and use, to very specific and complex, concerning information on age-related molts and plumages that Pyle could incorporate into a revision. It is beyond the scope of this review to address all these ideas, but we provide a summary of common themes and list suggestions that the reviewers thought should be considered when the book is revised, noting that the 12 contributors to this review unanimously agree that Part II is a seminal effort that should continue to be updated.

    With some reiteration of comments from the previous questions, the reviewers thought that the book could be improved in three general areas: formatting and organization, use of graphics, and reference materials. There was strong support among reviewers for greater use of images, both within the text and in references, the latter including previously published or diagnostic images that are accessible online (see question no. 8). This need was noted especially where subspecies or subjective degrees of feather wear and the color of soft parts are distinguished. Most also agreed that Pyle's simplified use of “color names found in current ornithological literature and field guides” is inadequate and that a color palette should be included for reference. The black-and-white and gray-scale drawings were often considered too basic and lacking in sufficient detail. Under the category of reference materials, reviewers wanted to see greater attribution of museum materials (e.g., used or not, how many specimens examined, what collections). The rich Russian literature on the Charadriiformes could have been used for many of the Beringian species. Concerning issues of formatting and organization, reviewers thought that more use of bold and italic type could focus attention on key features used for aging, sexing, and identification. A thorough copyediting of Part II would be worthwhile. And a great majority felt that the extent of the use of abbreviations and acronyms presented a steep learning curve for the book, though most were resigned to their necessity to save space.


This book (along with Part I) completes a monumental effort to aid in the identification of North American birds. It belongs on the bookshelf (or bird-banding or museum table) of anyone who handles birds or has questions about a bird's age, sex, plumage, stage of molt, or taxonomy. Part II stands to be a major reference for some time and will only improve in usefulness as people apply, question, and revise its findings.



American Ornithologists' Union. 1957. Check-list of North American Birds, 5th ed. American Ornithologists' Union, Washington, D.C. Google Scholar


E. S. Bridge 2009. [Review of Identification Guide to North America Birds, Part II.] Waterbirds 32:360–362. Google Scholar


M. Gustafson 2009. [Review of Identification Guide to North America Birds, Part II.] Wilson Journal of Ornithology 121:664–665. Google Scholar


M. Hipfner 2009. [Review of Identification Guide to North America Birds, Part II.] Marine Ornithology 37:93–95. Google Scholar


T. L. Lloyd-Evans 2009. [Review of Identification Guide to North America Birds, Part II.] Condor 111:764–766. Google Scholar


P. Pyle 1997. Identification Guide to North American Birds. Part I. Slate Creek Press, Bolinas, California. Google Scholar


K. Winker , and S. M. Haig , Eds. 2010. Avian subspecies. Ornithological Monographs, no. 67. Google Scholar
© 2011 by The American Ornithologists' Union. All rights reserved. Please direct all requests for permission to photocopy or reproduce article content through the University of California Press's Rights and Permissions website,
R. Todd Engstrom, Robert E. Gill, Daniel W. Anderson, Clait Braun, Eli S. Bridge, William S. Clark, Bruce Eichhorst, Jules Evens, David C. Evers, Floyd E. Hayes, Alvaro Jaramillo, Ian L. Jones, and Kenneth D. Richkus "Book Reviews," The Auk 128(1), 184-187, (1 January 2011).
Published: 1 January 2011
Back to Top