Senior Theses 2004
Gina M. Skurka (2004). Sessile on the dock of the bay: a
study of fouling community succession
Faculty advisor: Nancy F. Smith
Disturbance can create opportunities for non-indigenous species to settle and invade an established community. Subsequently, such events can influence succession and community structure. Invasive species, such as the Asian green mussel, Perna viridis, have the potential to alter community composition due to rapid growth and high reproductive effort. This study examines succession of a fouling community at a marina in St. Petersburg, Florida, for one year and investigates the effect of green mussels on community structure. Monthly settlement, species diversity and relative abundance of fouling organisms were monitored on artificial settlement arrays in the presence and absence of green mussels. I identified 22 sessile species between January and December 2003. Barnacles, bryozoans, and colonial tunicates, were the first animals to colonize and establish on settlement plates in January 2003. Succession was followed by polychaete and tunic ate establishment in April, and oyster, sponge, anemone and green mussel recruitment in May. Subsequently, sponges dominated the plates from October through December. Predation, mortality, and slough-off events altered community composition throughout the year, occasionally resetting succession. Experimental results indicate that green mussels did not affect community structure. This was most likely due to the low densities (< 10 % cover) observed during the study. Understanding succession and the effect of non-indigenous species on native communities has significant implications for conservation as the introduction of non-indigenous species has become increasingly one of the most important causes of biodiversity loss.