Wednesday, September 14, 2016

Review: The Second Nebraska Breeding Bird Atlas

The Second Nebraska Breeding Bird Atlas. Wayne J. Mollhoff. Bulletin of the University of Nebraska State Museum. Volume 29. 2016. $30.00 softbound.

This book gives the results of Nebraska’s second breeding bird survey. The first census was conducted in 1989. This book, a 30-year update, is essential reading for anyone remotely interested in Nebraska’s breeding birds. The book consists of accounts, one page for each species, for each of the state’s 225 breeding bird species.

A 29-page introduction describes the methods used for the two atlas projects. Nebraska’s ecology and climate are also covered. A short discussion of changes of breeding bird distribution concludes this introduction. Finally, there is a page or two on how to interpret the species accounts.

Each account consists of a short description of the status of each species. These paragraphs include habitat and distributional notes. Comments are included on population trends, along with data from Breeding Bird Surveys. Two charts follow, one describing habitat use and the other, patch size.

Aside from the perennial problem of the variability of identification abilities by observers, two weaknesses stand out. First, patch size is the estimated size of the habitat in which birds were found breeding. Mollhoff admits that patch size is an odd concept. Reporters differ in their ability to estimate patch sizes. Often observers did not report patch sizes. The other “weakness” is that many more observers participated in the second survey. The result is that one does not know if population increases are the result of actual increases or an artifact of having more observers. To his credit, Mollhoff points out this problem where it occurs.

Each account concludes with two distribution maps, one for the first Atlas, the other for the current survey. These maps are invariably fascinating. They allow the reader quick access to distributions and to geographical trends. The blocks with breeding birds are indicated by a red dot. The result is a flat representation of occurrence, but not a display of relative abundance.

The book ends with 10 appendices. These statistically compare the two atlas surveys and present county-by-county analyses. Atlas blocks are described, species at risk are listed, and potential additional species are discussed. Finally Mollhoff presents acknowledgments, references, and a checklist of Nebraska’s breeding birds.

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