BirdLife International. 2004. BirdLife Conservation Series, no. 12. BirdLife International, Cambridge, United Kingdom. xxiv + 374 pp., tables, text figures, maps, black-and-white line drawings, 7 appendices. ISBN 0-946888-53-1. Cloth, €30.00 (approximately $57).—Effective bird conservation requires knowledge of distribution, relative abundance, and population trends at multiple geographic scales. Obtaining this information for a continental avifauna poses considerable challenges, especially in Europe with its 52 countries, numerous languages and cultures, and disparate resources available for monitoring bird populations within each country. Synthesizing the available information on the status and trends of all European birds into a single volume is an enormous yet essential task necessary to direct bird conservation activities across the continent.

The second compilation of the conservation status of European birds, Birds in Europe appears one decade after the first summary produced in 1994 (reviewed in Auk 114:310–311). Its format is similar to the 1994 publication and emphasizes changes in population status that occurred during 1991-2000. The summary is translated into 10 languages, but the remainder of the text is in English. The introductory chapters cover various topics, including the legal context for bird conservation within Europe, data sources used in this report and their reliability, a lengthy discussion of the criteria used to assess conservation status, an overview of the results, and a list of conclusions and recommendations to guide bird conservation efforts during this decade.

Whereas the 1994 report discussed only species with unfavorable conservation status, species accounts in the current volume describe the conservation status for all 526 species that regularly occur in Europe. Each account consists of a brief paragraph summarizing population changes after 1990 and justification for assigning the appropriate conservation status to each species. Accompanying tables provide breeding population estimates and trends for each country and, for wintering waterbirds, similar information on winter populations. These data were obtained from four European bird-monitoring schemes and two large-scale databases to ensure that the most appropriate data were analyzed. A figure summarizes data quality used to assess conservation status, and a map depicts relative population sizes and trends within each country.

These accounts are followed by seven appendices. The first appendix is a large table summarizing the data provided in the species accounts. Remaining appendices provide various ancillary information, including occurrence of species by country, the protected status of each species in Europe, and information on the species assessment process used to produce this report.

Conservation status for each species was initially assessed using the International Union for the Conservation of Nature (IUCN) Red List Criteria to determine the potential for regional and global extinction; IUCN classifications of critically endangered, endangered, and vulnerable are familiar to most scientists involved in bird conservation. Species failing to meet any Red List Criteria were assessed against five categories of conservation concern (declining, rare, depleted, localized, and secure) developed by BirdLife International. Except for a handful of species considered data-deficient, each species is assigned, at least provisionally, to one of the IUCN or BirdLife categories. Each category is clearly defined, as is the quantitative approach for estimating European population trends used in these criteria.

The half-page devoted to each species provides a wealth of information. Population sizes and trend estimates for each country are expressed as a range between minimum and maximum values, accompanied by literature citations where available, though much information was obtained through communication with ornithologists and birdwatchers in each country. Data quality is assessed as poor, medium, or good, providing a basis to compare how data quality changed since the initial report. Conservation status assignments were somewhat subjective, especially distinctions between provisional and nonprovisional assignments, but such subjectivity is probably unavoidable.

The liberal use of acronyms may annoy non-European readers. For example, frequent reference to tables or appendices is necessary to understand the differences between SPEC1, SPEC2, and SPEC3, where SPEC stands for a Species of European Conservation Concern, and to decipher the perplexing set of identifiers used for European/Global IUCN Red List Criteria. Despite these annoying acronyms, the important information summarizing population size, trends, and conservation status can be understood by anyone having minimal fluency in English.

So how are European bird populations faring? During the past decade, the number of species considered to have unfavorable conservation status increased from 38% to 43% of the avifauna. Only 14 species improved from unfavorable to favorable status, as compared with 45 species whose status changed to unfavorable. Species associated with agricultural habitats continue to do poorly, mirroring trends apparent in North America. These results indicate that existing bird conservation activities are ineffective in achieving the goal of halting biodiversity loss across Europe by 2010.

This book provides an authoritative and coherent summary of the status of European birds. Everyone contributing to its publication should be congratulated for their efforts. It serves as an indispensable reference for anyone involved in European bird conservation and concisely summarizes the current status of the European avifauna for those with a global perspective. These data provide a benchmark against which future population changes can be measured, especially important now that the highly pathogenic form of the H5N1 virus has infected wild bird populations in Europe and could have a decidedly negative influence on population trends during the coming decade.