Fighting for shelter: Are aggressive Caribbean spiny lobsters the best den competitors?
Heldt, Katherine; Childress, Michael
Biological Sciences (College of Agriculture, Forestry and Life Sciences)
Caribbean spiny lobsters are highly gregarious and use shelters for protection from predators. In recent years, sponge loss events in Florida Bay have decreased the amount of natural shelters available for juvenile spiny lobsters, and aggressive behaviors exhibited at the den, suggest that den competition may increase after shelter loss events. To determine the influence of habitat loss on denning behavior, twenty juvenile lobsters were collected from eight high and eight low shelter locations. Each group (n=16) was observed daily in a mesocosm with ten crevice shelters. We measured the frequency of den use, den sharing and den fidelity of each individual and determined whether characteristics such as size, habitat type, health, etc. influenced denning behavior. To simulate a sudden shelter loss, five crevice shelters were removed from the mesocosm and behavioral variables were re-measured. Both size and habitat type played an important role in explaining denning behavior. Surprisingly, after shelter loss, den use and den fidelity decreased for large, aggressive lobsters. Understanding the impacts of habitat loss is especially vital for this economically important species, and these data suggest that vulnerability rather than aggression predicts which individuals remain in a den after shelter loss.