Covering only c. 0.8% of Earth’s surface, freshwater habitats are home to almost 45% of all fish species, 25% of all mollusc species, and harbour a relatively high species density compared to the terrestrial and marine environments. Given the wealth of biodiversity associated with freshwater environments, how does one go about identifying and assessing the values of freshwater ecosystems, habitats and species for conservation? This challenging question is the focus of this book, edited by P.J. Boon and C.M. Pringle, a UK freshwater policy advisor and a US professor of freshwater research, respectively. The editors contribute a number of chapters and there is input from 17 other authors. The assessment of conservation value is a pressing and contentious issue and the book provides a good overview of various approaches, both legislative and scientific.
One strength of the book is that each of Chapters 2–8 is co-authored by a pair of authors, one each from the UK and USA. This format allows careful comparisons of the approaches used in both countries. These chapters cover a number of key topics, including relevant legislative frameworks, underpinning philosophies, approaches for prioritizing freshwater values for conservation, responses to threats to freshwater biodiversity (including case studies), approaches for evaluating restoration potential, and approaches for assessing river and lake conservation values. Note that the book covers issues related only to lakes and rivers and does not specifically cover the assessment of conservation values of other freshwater ecosystems such as ponds or wetlands.
In Chapter 2 the results of a survey conducted by the editors are presented in which a number of freshwater specialists were asked to score various attributes (e.g. naturalness, rarity, diversity) as indicators of freshwater conservation value. Results were analysed by country (UK vs USA) and by professional grouping (researchers from universities and research institutes vs people working in conservation bodies vs river/lake/land managers and environmental regulators) for rivers and lakes, separately. Some patterns emerged from the data and, among other conclusions, the authors interpreted their results as indicating that the traditionally accepted criteria of naturalness, rarity, diversity and representativeness accurately summarize a general perception of freshwater conservation value.
To extend the scope of the book geographically and culturally interesting summaries of approaches used in Sweden, Australia and New Zealand, South Africa and in some developing countries are presented in Chapters 9–12. A sense of the urgency of freshwater conservation is generally communicated only in the latter chapters dealing with developing countries and Australia and New Zealand. The reader could be lulled into a false sense of security by chapters 2–9 as the complex legislative and scientific approaches employed in the UK, USA and Sweden are generally succeeding in conservation of freshwater biodiversity and ecosystems.
This book does not give the reader a sense of the great challenges that persist for freshwater conservation in the developed world, nor does it signal an emerging consensus or pathway that could lead to greater success in conserving freshwater species, habitats and ecosystems. Perhaps the authors will follow this book with one that analyses which approaches work best and which approaches have not worked. On the other hand, perhaps different approaches are needed to suit different cultural, historical and ecological circumstances and, thus, there is no single approach that works across a wide range of cultures and ecologies.
This little book covers a lot of ground, provides a broad overview of the topic, and is a well organized access point to a range of literature dealing with legislative and scientific approaches to assessing freshwater conservation. It is a valuable, up-to-date summary of some of the complex scientific and legislative issues in freshwater conservation currently being played out in many countries around the world.
