Introduction to Population Ecology. Larry L. Rockwood. Blackwell, Malden, MA, 2006. 339 pp., illus. $44.95 (ISBN 1405132639 paper).

The need for a concrete understanding of population ecology among all disciplines grows exponentially. This escalation is continually fed by changing land use, global climate change, more species invasions, and the myriad of other environmental problems that plague conservation efforts. Although often trained in traditional academic departments, students more and more embrace the once “alternative” pursuits of policy, management, or environmental consulting as mainstream careers. Accordingly, these professionals can readily put to use a solid understanding of how populations grow, decline, or interact. Such an understanding of population ecology should lead to wise decisions regarding management, especially of threatened and endangered species.

In his textbook, Introduction to Population Ecology, Larry L. Rockwood seeks to provide the background to integrate the basics of population ecology with applied challenges presented by conservation biology. Rockwood writes of his motivation to equip students with the mathematical understanding and critical thinking skills necessary to address questions that arise in the public arena. As an archetypal example, Rockwood suggests that both policymakers and federal employees need to be capable of competently discussing whether the introduction of wolves back into Yellowstone National Park has actually affected elk herds. Equally valuable, an emphasis on the nuances of population ecology facilitates the development of suitable research questions. Rockwood aptly acknowledges that ecologists frequently face challenges in developing proper methodology. An environmental consultant for a conservation project could use chapters of this book for brainstorming how to investigate extinction probabilities for small, isolated populations; for organisms that exhibit different life histories; or for species tied to other species through mutualistic or parasitic relationships.

With 30 years of experience teaching at the intersection of environmental science and policy at George Mason University, Rockwood correctly identifies the need for a textbook that achieves a balance between breadth of topics and depth of mathematics. As a new choice in population ecology textbooks, Rockwood's effort provides an up-to-date, comprehensive overview of population ecology that graduate students, and possibly select undergraduates, can readily understand. Rockwood takes the approach of most population ecology textbooks by first exploring single-species populations and then confronting more complex interspecific interactions. This textbook proves atypical, however, in that Rock-wood briefly covers mutualistic interactions and expands typical coverage of host–parasite interactions. In contrast with most other texts, these novel chapters appear before Rockwood's exploration of predator–prey dynamics, which precedes a final chapter on plant–herbivore interactions. In that chapter, Rockwood relies primarily on terrestrial examples, although aquatic ecologists interested in herbivory could apply this information to freshwater systems.

The introductory sections of each chapter constituted my favorite feature of the text, as Rockwood did a superb job of succinctly summarizing ecological topics, clearly defining concepts (in boldface), providing a clear review for students, and laying the groundwork for incrementally developing the mathematical constructs. The book is well referenced, often providing the reader with several avenues to explore topics in more depth. Faculty employing Rockwood's text could test problem-solving ability more frequently by creating their own exercises that go beyond the limited in-text examples and questions in the appendix. Throughout the text, Rockwood highlights instruction on how to interpret trends in important variables within both simple and more complex models. This emphasis allows students to determine more easily whether a population might be increasing, fluctuating, or crashing. Establishing this mathematical background sets the stage for the applied purpose of the text.

Rockwood's text covers the major topics relevant to population ecology. However, the average undergraduate, especially in a program that does not offer a concentration in ecology or environmental science, may have difficulty in negotiating the dense reading that accompanies the otherwise logical and well-constructed stepwise explanations of the models and assumptions. In the digital age, proper use of color often facilitates understanding of complex graphics, and the average undergraduate may respond better to such illustrations. The brilliant cover picture of a reddish purple rainforest tree frog does not mirror the book's style, however, as no color appears in the text. The monochromatic presentation bucks the trend of most undergraduate ecology texts. The figures in Introduction to Population Ecology primarily provide illustrations of the theoretical relationships predicted by various permutations of assorted models. But, of course, a textbook should not stand alone but should exist in concert with lectures and exercises.

Several chapters end with discussions of laboratory and field examples. Professors could further complement this text by focusing their own graphical examples on published literature. Furthermore, the book could serve as a valuable resource for investigating specific topics in population ecology or providing broad topical coverage for graduate students.

In the preface, Rockwood points out that population ecology can be approached at a variety of levels, depending on the mathematical background of the students and professor. Although it relies on advanced algebra rather than calculus and differential equations, this book often provides more than a basic introduction to population ecology. Examples include an in-depth discussion of differences between deterministic and stochastic models, substantial exploration of flaws in the assumptions of the logistic equation, three modifications of a Leslie matrix, and repeated exposure to the complexity of age-structured dynamics. While a discussion of these topics holds value, it is unlikely that an instructor of a typical semester-long undergraduate course could adequately cover all the material Rockwood presents. This situation is not unusual, as all material in most other textbooks usually cannot be covered in a typical 14-week semester, no matter what the author's intent. Fortunately, Introduction to Population Ecology gives instructors ample material from which to choose their own emphasis.

The text of Introduction to Population Ecology achieves its goal of providing the mathematical background and basic ecological understanding that applied ecologists require to make wise management decisions. Nevertheless, management decisions do not exist in a vacuum of population ecology models, but must consider economic, political, and social consequences. To reach a professional audience faced with the everyday challenges of conservation biology, a perfect pairing to this text would be a supplement, or a course emphasis on case studies, that includes economic considerations, ethical dilemmas, or site-specific considerations. With this addition, the mathematical background Rockwood supplies, combined with knowledge of the multidisciplinary perspectives influencing conservation, could help enable us all to make wiser management decisions in the future.