Georgia Southern University Digital Commons@Georgia Southern Electronic Theses and Dissertations Graduate Studies, Jack N. Averitt College of Fall 2005 Sponge Community Structure and Anti-Predator Defenses on Temperate Reefs of the South Atlantic Bight Richard Robert Ruzicka Follow this and additional works at: https://digitalcommons.georgiasouthern.edu/etd Recommended Citation Ruzicka, Richard Robert, "Sponge Community Structure and Anti-Predator Defenses on Temperate Reefs of the South Atlantic Bight" (2005). Electronic Theses and Dissertations. 705. https://digitalcommons.georgiasouthern.edu/etd/705 This thesis (open access) is brought to you for free and open access by the Graduate Studies, Jack N. Averitt College of at Digital Commons@Georgia Southern. It has been accepted for inclusion in Electronic Theses and Dissertations by an authorized administrator of Digital Commons@Georgia Southern. For more information, please contact
[email protected]. SPONGE COMMUNITY STRUCTURE AND ANTI-PREDATOR DEFENSES ON TEMPERATES REEFS OF THE SOUTH ATLANTIC BIGHT by RICHARD ROBERT RUZICKA III Under the Direction of Daniel F. Gleason ABSTRACT The interaction between predation and anti-predator defenses of prey is important in shaping community structure in all ecosystems. This study examined the relationship between sponge predation and the distribution of sponge anti-predator defenses on temperate reefs in the South Atlantic Bight. Significant differences in the distribution of sponge species, sponge densities, and densities of sponge predators were documented across two adjacent reef habitats. Significant differences also occurred in the distribution of sponge chemical and structural defenses with chemical deterrence significantly greater in sponges associated with the habitat having higher predation intensity. Structural defenses, although effective in some instances, appear to be inadequate against spongivorous predators thereby restricting the distribution of sponge species lacking chemical defenses to habitats with lower predation intensity.