- Restoring Wildlife: Ecological Concepts and Practical Applications, 2nd ed.
Restoring Wildlife: Ecological Concepts and Practical Applications by Michael L. Morrison is a straightforward presentation of the theoretical and applied aspects of wildlife ecology pertaining to the restoration of animal populations. Restoring Wildlife is an expanded, reorganized version of an earlier text, Wildlife Restoration: Techniques for Habitat Analysis and Animal Monitoring (Morrison 2002), but with a greater emphasis on ecological theory and the addition of four case studies. Restoring Wildlife is not overly technical and is targeted toward wildlife managers that may be involved in restoration projects. The text is well organized and, in addition to the case studies, includes numerous applied examples of key concepts.
Chapter 1, "Introduction: Restoring and Preserving Wildlife," describes the premise of the book, defines a few fundamental concepts, and outlines the chapters to come. Chapter 2, "Operating Concepts," emphasizes that the act of restoration requires that the manager consciously and specifically identify the condition to which something is to be restored. This may seem trivial, but even so-called "pristine" pre-Columbian landscapes in North America were profoundly altered by humans, so deciding on the desired condition to which an ecosystem is to be restored is no easy task. Morrison thoroughly discusses the importance of this process.
In chapter 3, "Populations," Morrison stresses the need to identify the spatial structure of the population to be restored and explains the concepts of captive breeding, translocation, and genetic management of captive and reintroduced populations. This chapter provides a thoughtful discussion of the role of reintroduction to wildlife restoration. Population viability is discussed, but mostly the genetic aspects; I would have liked to have seen a more thorough discussion of demographic issues specific to small population management. For example, when large and small populations experience the same levels of demographic variation, the small population has a much greater chance of extinction (White 2000).
In chapter 4, "Habitat," Morrison again emphasizes the need for managers to define the temporal and spatial scales and biological organization levels (for example, ecosystems, communities, species, or individuals) that they will be targeting. He discusses a number of habitat variables that can be measured but also describes common pitfalls of characterizing wildlife-habitat relationships. For example, animal density may be a poor indicator of habitat quality; habitat associations developed in one area may not work well in another; and habitat use may be affected by the presence or absence of competitors or conspecifics. Finally, Morrison describes some common techniques for measuring vegetation. Though the discussion is probably too general to be used to design a sampling protocol, this section is useful nevertheless by introducing the reader to the assortment of methods available.
New to this edition of the book is the chapter "Assemblages" (chapter 5), beginning with a description of the assembly rules concept and how those rules can affect ecosystem restoration efforts. For example, the order in which species are introduced into a new environment can produce very different results (introducing prey before the predators, for example, or conversely). Unfortunately, we know very little about assembly rules and how they function, or even if such rules exist. Morrison explains that there is also a certain amount of stochasticity to the process that only adds to the mystery. Though assembly rule generalizations are few in the book, one point Morrison makes is that most population processes and habitat relationships operate at the species level. Although an assemblage of species may be the target for restoration, management efforts must ultimately be focused on individual species.
In chapter 6, "Desired Conditions," Morrison again emphasizes that managers should identify specific, quantitative restoration goals. His point is that hard choices have to be made; given invasive species, climate change, and past extinctions, comprehensive restoration may not be possible and activities that favor some species will undoubtedly disfavor others. Morrison discusses ways to establish goals for plants, animals, and ecosystem function and presents an excellent synopsis...