Interspecific competition for shelter is a driving factor in determining abundance and distribution of of the Caribbean spiny lobster, Panulirus argus, and Florida stone crab, Menippe mercenaria. Former M.S. student Eliot Hart used a combination of field and laboratory experiments to demonstrate the dominance of the stone crab in benthic habitats. Stone crabs won in direct competition in mesocosm experiments, regardless of the number of lobsters present, the presence of co-sheltering species, or the order of introduction of competitors. Artificial manipulation of stone crab abundance in the field had a direct and negative correlation with lobster abundance.
Our study of trophic ecology allows us to examine food webs from a broad perspective. We commonly use an approach incorporating stable isotopes to examine an array of community relationships. Recent M.S. graduate Devon Pharo examined the effects of hard-bottom habitat degradation on the ecology and biology of the Florida stone crab, Menippe mercenaria. This project was related to research on sponge community restoration, focusing on the potential impacts of cyanobacteria blooms and subsequent sponge die-off to nutritional condition and trophic ecology of stone crab and other benthic organisms dependent on hardbottom habitat.
Sea Cucumber Ecology
Sea cucumbers appear to occupy an important trophic niche in the Florida Keys as a prey item for sea turtles (and increasingly humans!) and a top-down controller of benthic microalgae in seagrass beds. Interestingly, there are two morphotypes of Holothuria floridana, but the ecological role and reason for phenotypic differences are unclear. Former graduate student Nate Berkebile investigated the differences in predation on foraging impacts of the two morphotypes. This knowledge will help build a foundation for conservation and informed management.