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Conservation of Exploited Species. Reynolds, J. D., G. M. Mace, K. H. Redford, and J. G. Robinson , editors . 2001 . Cambridge University Press , Cambridge, United Kingdom . Conservation Biology Series 6. 544 pp. $120.00 (hardcover). ISBN 0-521-78216-3 . $44.95 (paperback). ISBN 0–521–78733–5.

This volume contains 22 chapters dealing with a broad range of topics on the conservation of exploited species. Overall the chapters are excellent; the volume is very well done and a treasure trove of delights. It contains a good mix of aquatic and terrestrial topics, biology and management, theory and data. The chapters are uniformly well written, and the entire volume would make an excellent subject for a graduate seminar.

The overriding theme of Conservation of Exploited Species is that exploitation is one of the major causes of conservation concern, and the chapters within examine this theme from a range of viewpoints. Parts I and II consist of series of chapters on the theory and practice of sustainable harvesting of populations. The contribution by Ludwig entitled “Can We Exploit Sustainably?” presents the central challenge. Ludwig concludes that we have more than sufficient scientific knowledge, but we have failed to use this information. Punt and Smith review the history of maximum sustainable yield; Lande, Saether, and Engen explore sustainable harvesting of fluctuating populations; Milner-Gulland explores spatially structured populations; and Wade provides a comparison of statistical methods used in population dynamics and management advice. Emerging from all these chapters is a unifying argument that we know how to exploit our environment sustainably, accounting for uncertainty, fluctuating populations, and spatially structured populations, but do we have the institutional structures to use this knowledge and implement sustainable strategies?

Part III focuses on the relationships between the life histories of species and their exploitation, with chapters on the following topics: fishes ( Reynolds, Jennings, and Dulvy ), mammals ( Purvis ), trade in wild birds ( Beissinger), meat hunting in tropical ( Fa and Perez ) and plant conservation ( Peters ). Part IV, entitled “From Individuals to Communities,” contains chapters on individual behavior by Sutherland and Gill; the Allee effect by Petersen and Levitan; life-history theory and harvesting by Kokko, Lindström, and Ranta; and genetic impacts by Law. This section then moves into ecosystems. Kaiser and Jenning explore the ecosystem effects of exploitation from a trophic perspective. Redford and Feinsinger evaluate how subtle ecological interactions may lead to significant ecosystem changes from levels of exploitation that by normal standards appear easily sustainable. This chapter poses the most serious challenges to the traditional theory of exploitation. The authors suggest that many species may be eliminated through the sustainable exploitation of other species as a result of complex life-history and behavioral connections. If this is the case, then sustainable exploitation of target species may have much more serious biodiversity costs than most trophic-based models would suggest. This question is worthy of much more exploration.

Part V, entitled “Conservation Meets Sustainable Use,” includes a chapter on pest control of kangaroos by Grigg and Pople and arctic exploitation and conservation by Gunn. Hutton and Dickson explore the concept of conservation by exploitation, relying primarily on African wildlife examples, for which managed exploitation has been used to provide revenue to local people and in turn encourage habitat protection. They conclude that this concept can work. Sanderson considers the political dimension of conservation.

The final chapter in this volume is by Robinson, who considers the issue of sustainable use as a conservation measure. He considers three objectives—species conservation, ecosystem health, and human livelihood—and suggests indicators of sustainable use as well as general approaches to satisfying these objectives.

Overall, I would like to have seen more emphasis on two topics, ecosystems and institutions. How ecosystems respond to exploitation is the most pressing biological question, yet most of the chapters continue the traditional emphasis on single species. Thus, this book is an interesting study in contradictions. Whereas several chapters emphasize the potential for exploitation as part of a conservation strategy, others emphasize the threats of exploitation. This contradiction is one of the most interesting features of the book. Even more important, in my view, are the institutional structures that guide exploitation. Sustainability is primarily a result of institutions much less than of biology. The editors are to be commended for including two chapters on institutions. I only wish there had been more.