Life histories in an epifaunal community: coupling of adult and larval processes

Marine invertebrates growing epifaunally on red mangrove (Rhizophora mangle) prop roots in the Indian River, Florida, USA, were studied in a small mangrove island (Jim Island) through which a number of channels had been cut. Roots hanging down into the water supported diverse epifaunal communities including sponges, oysters, barnacles, bryozoans, and ascidians. To determine what factors control species' population dynamics and contribute to the high degree of spatial heterogeneity characteristic of communities in this unique habitat, two hypotheses were tested: (I) Distributions of species on the roots are controlled by differential growth and mortality due to physical features; and (2) Recruitment, as influenced by larval supply, structures the community.