8 SEPTEMBER 2012 The name of Michael B. New has been nearly synonymous with the science of prawn aquaculture over the past 30 years, if not longer. He published landmark reviews of the global situation with prawn aquaculture in 1990 and 1995 and well-regarded FAO technical manuals in 1985 and 2002. This 544-page book might be seen as the culmination of a long career supporting the global development of prawn aquaculture with state-of-the-art science and technology information. The book is co-edited with four other prominent prawn aquaculture scientists, Wagner Valenti of Brazil, Jim Tidwell and Lou D’Abramo of the USA, and Methil Kutty of India. The 24 chapters were written by 44 contributors, representing 10 countries, including leading producers China, Thailand, India, and Bangladesh. Many other individuals from many more countries are credited in the acknowledgments as correspondents. Although the book is heavily weighted to contributions from authors in developed countries with temperate climates, where prawn production is modest, it is good to see authors from developing countries participating meaningfully in this book project. One hopes that the information contained in this book will reach the centers of production in east, southeast and south Asia, where it is likely to have the greatest impact and benefit. The book represents a comprehensive treatment of the subject, covering all the essential topics expected in a book on the aquaculture of a particular species. Although the book is subtitled “Biology and Farming,” there are only two chapters that explicitly address biology. Nonetheless, all chapters make reference to biological aspects of freshwater prawns, but the book is heavily weighted to farming. There are chapters on reproduction, spawning, and hatcheries; nutrition and feeds; disease and health management; genetics; processing and marketing. There are five chapters on grow-out systems, including monoculture, polyculture and integrated systems, and culture in temperate zones. I found plenty in the book to satisfy my personal interest in pond aquaculture. Although the treatment of many topics is covered more comprehensively in other books specific to a particular topic (e.g., nutrition, disease, water quality), this book makes reference to the topic by providing specific information about prawn aquaculture. There are three chapters that address the culture of prawn species that are perhaps less well-known or cultured than the giant river prawn Macrobrachium rosenbergii. In particular, the chapter on culture of the oriental river prawn M. nipponense is fascinating. This species is endemic to rivers in China and is more cold-tolerant than the giant river prawn, although size-atharvest is smaller. In fact, there is greater production of oriental river prawn in China than the non-native giant river prawn, which is a species introduced from Thailand. There is also a chapter on culture of the Amazon River prawn M. amazonicum, another species that is smaller than the giant river prawn, but one that avoids concerns about endemic biodiversity in the event of escape from production facilities, particularly in species rich areas such as the Amazon Basin. At least 26 other species of Macrobrachium have culture potential in different parts of the world, some of which are discussed in more detail in one chapter. The role of prawns in fisheries enhancement programs is under-appreciated. A chapter that surveys farming and enhancement activities written by New and Kutty suggests great potential, at least as indicated by experiences in India and Thailand. Government-supported hatcheries have produced juveniles for stocking rivers, lakes, and reservoirs in these countries. In river systems where dam construction, water pollution, or other habitat alterations have disrupted the natural life-cycle of prawns, enhancement programs can be effective. One of the most difficult and troublesome aspects of prawn culture is the wide size variation, including three male morphotypes, that develops in populations of stocked animals. The fact that growth is regulated in large measure by social interaction presents difficulties for management. This feature was first described by prawn pioneer Takuji Fujimura in 1972. The chapter on this topic, written by Ilan Karplus and Amir Sagi of Israel, provides good practical recommendations for management of size variation, including supplementary shelters, selective harvesting, size grading, and monosex culture. This brings me to the chapter on genetics, which adequately covers the topics of population genetics, genetic management of broodstock, and sex-reversal and monosex culture. It is somewhat surprising that such little work has been done on genetic stock improvement with prawns, although this is an issue with many species in aquaculture. One of the more interesting parts of this chapter is the section on monosex culture, specifically all-female culture, as a way to maximize productivity. This might seem counter-intuitive in the context of the impressive size of blue-claw males. However, the analysis indicates that female prawns do not develop the same kind of size variation as males and, particularly at high densities (>40/m2), all-female culture results in the greatest economic returns. Implementing the technology of all-female culture involves several steps, although the sex-reversal protocols are well-established in finfish. It seems that this approach is Freshwater Prawns: Biology and Farming John A. Hargreaves 1 Book Review (CONTINUED ON PAGE 18) Many of the books reviewed in World Aquaculture are available at a discount to WAS members at www.was.org. 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