New World Blackbirds: The Icterids.—Alvaro Jaramillo and Peter Burke. 1999. Princeton University Press, Princeton, New Jersey. 432 pp., 39 color plates, 17 figures. ISBN 0-691-00680-6. Cloth, $49.50.—The New World blackbirds exhibit exceptional diversity in morphology (ranging from some of the smaller Agelaius and orioles through the giant oropendolas) and ecology (occurring in a wide variety of habitats including marshes, grasslands, deciduous forests, and tropical wet forests). It is their nearly unparalleled diversity in social behavior, however, that has attracted the attention of many ornithologists. Among the blackbirds one can find species that are socially monogamous (many orioles), highly polygynous (caciques, grackles, and oropendolas), cooperative breeders with low levels of polyandry (Brown-and-yellow Marshbird [Pseudoleistes virescens], Bay-winged Cowbird [Molothrus badius]), colonial breeders (oropendolas), and obligate brood parasites (most of the cowbirds). Thanks to this diversity, the icterids have been the focus of much research and have figured prominently in the development and testing of many theories in behavior, ecology, and evolution.
Jaramillo and Burke have produced a book that serves as a guide to the natural history of this fascinating family of birds. Their stated goal was not to produce a field guide or a scientific monograph, but rather to give an overview of the natural history of blackbirds that will serve as a “starting point for anyone interested in the icterids” (p. 9). To do this, they provide detailed species accounts, most of which are several pages long. A total of 103 species is included (a somewhat larger number than that commonly recognized because Jaramillo and Burke include taxa that are “widely regarded” to be full species). Also provided are detailed accounts of an additional six subspecies that differ markedly from other populations of the same species (e.g. Fuerte's Oriole [Icterus spurius fuertesi]).
The species accounts are well organized, giving details of identification, voice, plumage, geographic variation, habitat, behavior, nesting, distribution and status, movements, and molt patterns. Each account ends with a list of relevant literature to which the interested reader can turn for more details. Each species is also shown in a detailed color plate that includes a range map and, in many cases, shows plumage variation associated with sex, age, molt, and/or geography. The plate for Red-winged Blackbirds (Agelaius phoeniceus), for example, shows 13 individuals of various age/sex classes and subspecies.
By far the greatest strength of this book is the extensive literature that the authors have amassed and summarized for each species. The bibliography includes more than 1,000 citations, including several theses and papers in relatively obscure journals. Moreover, the authors do a good job summarizing the literature for each species, making it possible to look up any blackbird of interest and quickly learn virtually all that is known about its morphology and plumage (the details of geographic variation are quite good in most cases), voice, distribution and status, and behavior (particularly breeding behavior, which has been the focus of many studies). The job of summarizing was no small task for species that have been the target of numerous studies (e.g. Red-winged Blackbird and Brown-headed Cowbird [Molothrus ater]). Thus, this book will serve as an extremely useful reference for those interested in the natural history of blackbirds.
The primary weakness of this book is that it gives relatively little in the way of an overview of the general trends and patterns for this diverse family of birds. That is, little attempt is made to place the detailed species accounts into a broader context of evolutionary and behavioral theory. Systematic relationships among blackbirds are touched upon, as are some general behavioral and evolutionary issues, but the treatment is extremely brief and superficial. Similarly, it is difficult to glean from this volume general patterns of life histories, plumage variation, ecological groupings, mating systems, and parental behavior, nor is there any treatment of the interaction between humans and blackbirds (e.g. conservation issues relevant to the rarer forms).
Given the above, this volume will be most useful for those generally interested in blackbirds and those with very targeted, species-specific questions, such as “what are the patterns of geographic variation in Streak-backed Orioles (Icterus pustulatus)?” or “which species are parasitized by Giant Cowbirds (Scaphidura [Molothrus] oryzivora)?” However, those interested in more general questions such as “what are the patterns of sexual dimorphism in blackbirds?” or “how do food resources affect blackbird distributions?” will have to extract and synthesize the information themselves from the species accounts. Ornithologists interested in questions of the latter type will do better to turn first to more-focused monographs (e.g. Searcy and Yasukawa 1995), or to the excellent book by Gordon Orians (1985), even though the latter is nearly 15 years old and targeted at a lay audience. Indeed, a hybrid between the synthetic approach of Orians (1985) and the exhaustive, up-to-date literature survey of Jaramillo and Burke would be a welcome and useful addition to the ornithological literature (a hint to any of you looking for a book to write!).
By and large, the illustrations by Peter Burke are detailed, accurate, and engaging, making this book handsome as well as useful. However, the choice of background color for some of the plates is questionable. This is particularly true for some of the blackbirds and grackles, whose portraits fade into the dark backgrounds. Aside from this quibble, the plates do an excellent job of portraying the birds in realistic poses and settings. Similarly, the text figures do a good job of showing variation in plumage for a few confusing groups or species pairs.
In summary, this book is an excellent and detailed species-by-species account of the natural history of a very diverse and interesting group of birds. Although it is difficult to extract general behavioral trends and evolutionary patterns from this book, the information content is high, and one can easily find the details relevant to any particular species of interest. It is, as the authors intended, a very good starting point for those interested in the biology of icterids.
