This book sets out to summarize the extensive body of research on farmland bird conservation in Britain. It opens with a chapter on the history of agriculture in Britain, from the beginnings of woodland and shrubland clearance by Neolithic farmers, through the devastation caused to wetlands and open semi-natural habitats by drainage and enclosure, to changes in agricultural practice since the Second World War. All of these changes have had profound effects on the birds that managed to colonize, persist and even in some cases prosper in agricultural habitats. In the first of three main sections the authors describe in detail the bird communities of fields and field boundaries, as well as those of grazed semi-natural habitats such as heathland and downland.
The meat of the book is in the next two sections, summarizing the findings of half a century’s research into the patterns and mechanisms of change in farmland bird populations. These include chapters on population trends, demographic responses to agricultural changes and practices, and 16 detailed species case studies, supported by helpful summary tables. With almost 1,000 references the book provides an exhaustive compendium of current knowledge. I found it a telling catalogue of both the power and the limitations of science.
On the one hand the case studies of corncrake, stone curlew and cirl bunting show how detailed research, followed by the testing and deployment of targeted measures, has successfully reversed population declines. On the other, these are only a fraction of the thousands of plant and animal species inhabiting the countryside, and despite decades of research and billions of Euros in agri-environment subsidies, wider deterioration of the populations of birds and other species has hardly been dented. I can’t help feeling that we need a more ambitious approach to conservation, to augment that of species-specific tinkering.
There is a brief discussion of the objectives of conservation, which dismisses large-scale re-wilding as impractical and proposes the more modest aim of reversing the declines of species which were, until recently, familiar farmland species. I would have liked more thoughtful discussion on this topic. There are good arguments for conserving recently-declining species: for their cultural and aesthetic values and for their usefulness as indicators of a healthy environment. However, there are also compelling arguments for more ambitious baselines: for restoring a few large-scale examples of the wet and wooded landscapes that would have characterized the British Isles before agriculture, for example. Might re-wilding in some places, and ‘sustainable intensification’ in others (Godfray et al., Science, 327, 812–818) be more effective than trying to combine crop production and conservation in the same fields?
Although their focus is largely on the latter approach, the authors raise this and other questions in the final chapter, laying out what they see as three key research areas for the future. What are the likely trade-offs and synergies between biodiversity conservation, food production and ecosystem service provision? To what extent, and at what spatial grain, should we aim to separate land for production and land for conservation? How will climate change affect our answers to those questions? These are important and multifaceted questions to which as yet there are few clear answers.
A further challenge is to integrate local, national and global conservation issues and priorities. The food we eat in Britain, the biofuel feedstocks we grow or import, and the land-use choices we make here, have direct and indirect effects on birds and other species in agricultural lands far beyond these shores. Grappling with globalization is largely beyond the scope of this book but for those looking for a thorough summary of what is known about conserving birds in British farmland Bird Conservation and Agriculture will be an important reference.
