Development of an Epifaunal Assemblage on an Estuarine Artificial Reef

Abstract

Twelve Polyolefin™ cones were placed in Choctawhatchee Bay, Okaloosa County, Florida, on 20 Oct. 1987, as an artificial reef to examine the succession of the associated epibenthic invertebrate assemblage and its relationship to environmental factors. Ninety-five epifaunal settling plates with individual surface areas of 706.5 cm2 were removed from the reefs. The epifaunal settling plates bore 124,893 organisms from 90 taxa. The number of taxa and individuals associated with the reef gradually increased from deployment in Oct. to a maximum in June. Species diversity tended to increase through the 12-mo study. Coverage by the epifauna stabilized after 4 mo of deployment, A canonical correlation model attributed 86% of the variation in taxa abundance to variation in the independent variables equatorial moon position, salinity, temperature, reef module surface area, absolute time from noon, and vertical height of each settling plate above the substrate. Initial colonizers were typically motile organisms that were gradually succeeded by sedentary organisms. Arborescent bryozoans may have created a complex microhabitat, which facilitated the colonization of grazing species such as gastropods.