STUDYING METAPOPULATION EFFECTS IN PREDATOR-PREY SYSTEMS

It has been suggested that many predator‐prey systems persist, despite unstable local interactions, due to metapopulation processes: movement of individuals among largely independent local populations. I review 13 possible examples of this phenomenon all I could find in the literature—and find that each either lacks convincing data or is not a true metapopulation. Most of the examples rely on evidence of local extinction and recolonization, only a few using direct experimental methods; I discuss the advantages and disadvantages of these methods, as well as alternatives. I also consider the ways these systems deviate from having pure metapopulation structures, and conclude that most large‐scale spatial population structures will not fit cleanly into a metapopulation vs. within‐population dichotomy, but rather combine features of both. This will necessitate use of powerful and focused methodology (in particular, experimentation) to directly describe movement rates and patterns, rather than use of crude observational data (e.g. extinctions) to make inferences about movement. Copyright © 1991, Wiley Blackwell. All rights reserved