The Colorado Breeding Bird Atlas.—Hugh Kingery (editor). Illustrated by Radeaux. 1998. Published by Colorado Bird Atlas Partnership and Colorado Division of Wildlife. Distributed by Colorado Wildlife Heritage Foundation, Denver, CO. 640 pp., 16 pages of photos, numerous black-and-white illustrations, figures, tables, and maps. ISBN 0-9668506-0-2. $34.95 (cloth).
After 8 years of intensive data collection and two years of writing and data analysis, it is nice to finally see a finished version of The Colorado Breeding Bird Atlas, the first work of its kind from my home state. Any effort to document the breeding of all avian species within a state the size of Colorado, with habitats ranging from semi-desert to alpine tundra is a monumental task in itself. To produce such a thorough and detailed work is most impressive.
The initial portion of the atlas is a summary of the organization of the book, with details on types of information included, an overview of methodology used to document breeding species, and some broad data analysis showing statewide patterns in the breeding-bird data. In general, that section is longer and far more detailed and gives the reader better information than most breeding bird atlases. Particularly interesting and useful are tables and maps giving information on numbers of species confirmed breeding per block and latilong, and summaries of the species with highest confirmation rates and abundances. Also useful, especially to the layman, are the 16 pages of color photographs that show examples of different habitats and types of breeding confirmation. The section on the habitats found in the state is extremely well done. Although brief, each description contains information on distribution, structure, dominant plant species, and most commonly confirmed bird species in that habitat. This gives the reader an instant feeling for the bird and plant communities in question. There is no vegetation map for the state, however, with only a figure showing the general plant communities along the 39th Parallel as it crosses the state, and a map of physiographic regions. Thus, the reader cannot get more than a general feel for the distribution of habitats on the statewide level.
The bulk of the atlas is dedicated to the accounts of the 278 bird species either confirmed (264), or probably (14) breeding in the state. In general, those accounts were longer and more detailed than those found in most atlases, with two full (facing) pages dedicated to each species. Individual accounts were written by 30 different authors, which may bother those who prefer a consistent writing style. However, each account holds the same information in a standardized format and order, so that it is easy to move back and forth between accounts and find the same types of information. Editing appears to be excellent, with few errors in the text of the many species that I read carefully. The extent of literature cited in each account varies considerably, at least in part due to the amount of scientific background of the author. A few basic references such as Bailey and Niedrach's (1953) Birds of Colorado, and the Bent “life-histories” series, are typically included as well as the “classic” papers on natural history of a species. In several cases, a noted expert on a species authored that species account.
In addition to the text in each account, several other features are also included in each layout. Most importantly, a map of the blocks within a state where evidence for breeding was found is present for each species. Somewhat disappointingly, Colorado decided to use the format chosen by most atlases and overlay shaded blocks designating breeding evidence on a simple map of the outline of the state and its counties. Much more useful would be an overlay of symbols on a habitat map, such as used in The Atlas of the Breeding Birds of Alberta (Semenchuk 1992), or on a predicted distribution model, such as used by The Washington Breeding Bird Atlas. Such maps allow the reader to quickly determine distribution patterns based on habitat, or locate unusual breeding records or locations without referring to the text. Nevertheless, the maps are well done and distribution patterns of most species based on breeding records appear to be accurate. A few glaring errors can be found, such as an obviously accidental inclusion of some text in the margin of the Sage Sparrow (Amphispiza belli) map. However, general quality is very high. A single graph, showing number of blocks with breeding confirmation and habitats in which those confirmations took place is included with each species account, as is a table showing the type and number of breeding confirmations and extreme dates of confirmation. The graph might have been more useful as a percent of blocks where confirmation took place, but the table is extremely useful in looking at the breeding phenology of those species with many confirmations.
In addition to a standard appendix listing such block attributes as name, number, observer, and number of breeding species, two other useful appendices can be found in the back of the atlas. The first is a list of population estimates for the breeding species in the state. As pointed out in the text, those estimates are probably low for all but the colonial species and relatively rare species, but do provide at least a basis for conservation efforts and analysis. The second, a list of all the confirmed cowbird brood-parasitism records by block and species, also contains information that may prove useful for future study.
Overall, I would say that this is an impressive atlas. It is beautifully illustrated and organized, and contains the most comprehensive and detailed information published to this point on the breeding birds of Colorado. It is especially useful when used in conjunction with The Birds of Colorado (Andrews and Righter 1994). The price of $35.00 for cloth is very low for a volume of this size.—JOHN W. PRATHER, Department of Biological Sciences, University of Arkansas, Fayetteville, AR 72701, jprathe@comp.uark.edu