Meeting Abstract

P2.33  Jan. 5  Sponge Diversity on Mangrove Roots: Does Size Matter? KIMBLE, S.J.A.*; THACKER, R.W.; DIAZ, M.C.; University of Alabama at Birmingham; University of Alabama at Birmingham; Museo Marino de Margarita, Nueva Esparta, Venezuela sjkimble@uab.edu

Mangrove ecosystems are an important habitat for marine sponges, with submerged roots providing critical surface area for attachment. In addition, mangrove sponge diversity has been proposed as a bioindicator of coastal ocean health. Anecdotally, we observed that sponge diversity on mangrove islands might exhibit a positive correlation with island size. We tested this hypothesis by surveying mangrove islands ranging from six to 150 meters in circumference near the Smithsonian Tropical Research Institute�s Bocas Research Station, Bocas del Toro, Panama. Roots on transect lines placed around the islands were measured for length and the sponges attached directly to them were identified using field and microscopic skeletal characters. Sponge diversity was expressed as the number of species per root; diversity and island circumference were compared by regression. Preliminary results indicate a trend towards greater diversity on larger islands, in accordance with theories of island biogeography. Future directions will explore the phylogenetic structure of these communities and evaluate rates of colonization and migration between islands.