Methods for Fish Biology, 2nd edition

Chapter 17: Applied Fish Ecology

Brandon K. Peoples, Troy M. Farmer, and James H. Roberts


Peoples, B. K., T. M. Farmer, and J. H. Roberts. 2022. Applied fish ecology. Pages 643–694 in S. Midway, C. Hasler, and P. Chakrabarty, editors. Methods for fish biology, 2nd edition. American Fisheries Society, Bethesda, Maryland.


Applied ecology can be viewed as statistics attached to organisms. Applied fish ecologists rely on a variety of field and laboratory techniques, many of which are described in the other chapters of this book. Yet those tools are usually a preliminary step in the scientific process, being preceded by thoughtful consideration of study design and statistics and followed by interpretation of results and communication. Accordingly, ecological and statistical methods are inseparable. In addition to this volume, there are many resources for field and laboratory techniques (Bonar et al. 2009; Zale et al. 2012; Quist and Isermann 2017) as well as statistical analyses (Burnham and Anderson 2002; Guy and Brown 2007; Kéry and Schaub 2011; Legendre and Legendre 2012; Zar 2013). Moreover, numerous programs are available for conducting analyses, and choosing one is often a matter of personal preference. For these reasons, we differ from most chapters in this volume by focusing on identifying common methods, tools, and approaches rather than providing comprehensive details or programs for implementing them.

Numerous texts cover the conceptual aspects of fish ecology (Matthews 1998; Wootton 1998; Diana 2003; Walters and Martell 2004; Helfman et al. 2009; Ross 2013), and we refer readers to those sources for details on concepts. Instead, our goal for this chapter is to provide an overview of accepted and emerging methods used to answer common questions in applied fish ecology. Accordingly, this chapter is structured around ecological questions/issues rather than what can be done with a certain tool. We do this for two reasons. First, it helps to avoid the redundancy and confusion arising from using different tools to answer similar questions. Second, it represents our philosophy that ecology should be motivated by questions instead of tools; however, we recognize that the emergence of new tools can lead to generation of novel questions that had been previously unconsidered. In the next section, we begin by addressing a suite of common considerations and pitfalls associated with design and analysis of ecological studies and proceed with using basic types of studies to structure each section.