Chapter 2 - The Metapopulation Ecology of Coral Reef Fishes

Abstract

The ecology of coral reef fishes seems to invite a metapopulation perspective. A metapopulation structure is determined by the spatial arrangement of local populations, coupled with life-history traits that allow metapopulation dynamics to be enacted. There certainly is evidence to suggest that coral reef fishes may form metapopulations, at least when metapopulations are defined with reference to spatial structure and connectivity rather than extinction recolonization dynamics. Extinction recolonization may be evident at the edge of species ranges, such as within the Capricorn Bunker group of the Great Barrier Reef. Metapopulation dynamics are viewed as something more than extinction recolonization dynamics, and greater potential is seen for the presence of metapopulations among coral reef fishes. Demographic traits and behavior can vary even among very proximal populations, or among adjacent reef zones, reflecting a part of the independence of these populations. The population dynamics that result from dispersal patterns and local demography typically show asynchrony among populations, at least as indicated by recruitment data. To provide better answers, reef fish ecologists need, first and foremost, to continue the burgeoning trend of large-scale, interdisciplinary research on larval dispersal and demographic connectivity. At the same time, one should not accept too blindly the assumption that postsettlement reef fishes are sedentary; one should be looking to test this assumption in situations where it is likely to be violated.