The Effects of Dominant Species Removal on Subtidal Community Development

Acrylic panels were used to follow the development of the fouling community at Channel Points, Lynnhaven Bay, Virginia, from April through October 1979. The roles of Membranipora tenuis, an encrusting ectoproct, and Molgula manhattensis, a solitary tunicate, were studied by removing each species from the developing community on a weekly basis. Early colonization was dominated by Membranipora followed by Corophium spp. (Amphipoda), Polydora ligni (Polychaeta), and Balanus eberneus (Arthropoda). Molgula colonized the panels later in the study and became a dominant occupier of primary space by the end of the study. The removal of Membranipora and Molgula had no real significant effects on the development of this community. Because of yearly variation in the recruitment of Membranipora and Molgula, these two species were not as abundant or dominant as they were in 1977 and 1978 (Otsuka and Dauer 1982). Slow recruitment by Molgula until the latter stages of the study and decreased Membranipora recruitment after the initial observations probably reduced their importance to community development. Ineffectual removal of these two species also reduced the effect of these treatments.