Responses of common fouling organisms in the Indian River, Florida, to various predation and disturbance intensities

The response of some common fouling organisms to increased predation by scraping and decreased predation by caging is described. Substrate coverage by many colonial forms such as Perophora viridis and Diplosoma macdonaldi was not affected by changes in predation intensity whereas coverage by many solitary forms such as Spirorbis sp. and Styela plicata increased when predation was reduced. These differences in responses of colonial and solitary species may be because solitary species reproduce sexually and resettle newly opened space whereas colonial species can rapidly expand adjacent colonies into newly cleared space.