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Bird Conservation and Agriculture . Wilson, J. D., A. D. Evans, and P. V. Grice . 2009 . Cambridge University Press , New York , NY . 404 pp. $63 (paperback). ISBN 978-0-521-73472-1 .

Global food shortage, biomass production for the energy sector, increasing demand for agricultural products, continued loss of agricultural soils, and orientation of agriculture to the competitive world market are pathways for continued intensification of agricultural production in Europe and globally. For millennia European landscapes have been shaped by agricultural use. Western Europe is one of the “busiest, most picked over, most meticulously, most conspicuously used, most sumptuously and relentlessly improved landscapes on the planet” (B. Bryson. 2000. The English Landscape. Profile Books, London.). Successes and failures from Europe may inform conservation efforts in the face of increasing pressures on the land and its associated biological diversity. Bird Conservation and Agriculture, therefore, is a timely contribution to a discussion that will continue to shape conservation science in the decades to come.

The focus of the book is agricultural policies and practices and their effects on populations and conservation of birds in Britain. The first part introduces different types of agricultural environments and their bird communities. The second part presents trends in species composition and abundances in agricultural areas. The third and final part links these trends to agricultural change. The second and the third parts of the book, in particular, draw on a database of historical bird inventories in Britain that provide an unusual opportunity to assess efforts to conserve birds in response to changes in land use.

Chapter 1 describes the history of agriculture in Britain from the Neolithic to the EU Common Agricultural Policy. Technological progress largely determined change in agricultural practices until the late 19th century. A period in which market pressures were prime determinants of land use followed. After World War II, the political framework largely influenced the ways and means of agricultural production. Chapter 2 introduces the bird communities of tilled land and grasslands in Britain. Chapter 3 addresses areas in agricultural landscapes that are not farmed, but often affect bird occurrences and abundances. These areas include hedgerows, woodlands, gardens, farmsteads, walls, ponds, and water courses. Chapter 4 focuses on habitat quality for birds associated with human-influenced heathlands and grasslands across a topographic gradient in Britain. Upland heathlands are still fairly abundant in the northern parts of Britain. The main effects of agricultural activities that shape habitat quality in the upland heathlands are linked to grazing intensity. Grasslands in the south have been fragmented and reduced in area by agricultural reclamation, urbanization, and transition of agricultural areas to woodlands as a result of abandonment and afforestation. Calcareous grasslands, in particular, are areas of high plant and animal species richness and endemism in Europe.

Chapter 5 introduces trends and patterns of change in birds associated with agricultural lands. Overall, the abundance and range of 50% of these bird species and the area of grazed vegetation have declined substantially over the past 40 years. Seed eaters, insectivores, and long-distance migrants have been the most affected. Evidence for a cause-and-effect relation between changes in land use and bird abundances is reviewed in chapter 6. In general, agricultural intensification is inversely correlated with measures of species richness, range, and abundance of birds. Nevertheless, agricultural intensification affects different species in different ways. The chapter goes beyond birds to consider trends and possible causes of changes in plant and invertebrate communities. The chapter concludes with an examination of the responses of birds to reductions in agricultural intensity (e.g., conversion to organic farming, set-asides). Chapter 7 examines large-scale studies of the abundance of bird species and drivers of demographic trends. The authors acknowledge the limitations of generalizing model results to the distribution and abundance of birds over large areas. Similarly, due to confounding factors and regional differences, it is difficult to identify clearly the drivers of demographic trends, even at the rather crude scale of nesting success versus survival rate. Consequently, chapter 8 summarizes case studies of population trends and causes of such trends in 16 species.

Chapter 9 discusses changes in cropping cycles, pesticide use, agricultural improvement of grasslands, upland grazing, management of field boundaries, and interactions between predation and agricultural management as the main drivers of the decline of bird populations in farmed areas. The book concludes with a discussion of the future of birds and agriculture in Britain (chapter 10). The future of nature conservation in agricultural landscapes lies between the pessimistic scenario that assumes increasing productivity will exacerbate stressors on species and ecosystems and the optimistic scenario that assumes agriculture within the European Union will more effectively integrate production with environmental stewardship.

Because I am not from the United Kingdom, I sometimes found this book's perspective difficult and too specifically relating to the U.K. An alphabetical list of English and scientific names would have helped a great deal. More information on EU agricultural policies also would have helped me, and some of the figures relating to Common Agricultural Policy funding need correction. The book wavers between generalization and too much detail, illustrating the common challenge that transferability of ecological patterns and mechanisms is limited. In many respects the diversity of results (species and site specificity of effects) presented in the book therefore illustrates the need for adaptive management in agricultural ecosystems.

Overall, Wilson, Even, and Grice have written an informative book that is supported by an extended reference section. The book presents the key concepts and ideas currently discussed in the context of nature conservation and agriculture and the volume is highly relevant for readers in the United Kingdom.