NOCTURNAL FORAGING OF THE CARIBBEAN SPINY LOBSTER (PANULIRUS-ARGUS) ON OFFSHORE REEFS OF FLORIDA, USA

During night dives along randomly selected transects across sand, seag rass, and rubble on the reef flat of Looe Key, a spur-and-groove coral reef, spiny lobsters (Panulirus argus) from dens on the forereef were observed foraging on the reef flat, particularly on the extensive rub ble ridge and also relatively frequently in Thalassia. Subsequent samp ling of the rubble revealed hundreds of taxa of appropriate prey items , many at high densities; the density of Cerithium litteratum, a favou red food item, was as high as 180 individuals m(-2). Arthropods, espec ially spider crabs (Pitho spp.), were common in seagrass. Gut contents of 75 intermoult lobsters caught on offshore reefs at Biscayne Nation al Park and Dry Tortugas National Park included a myriad of prey items , predominantly molluscs-specially gastropods (49%), chitons (15%), an d bivalves (11%)-and arthropods (12%); many of the species in lobster guts were rubble dwellers, but some guts contained multiple prey pecul iar to seagrass and sand. It is concluded that Panulirus argus can for age successfully wherever suitable prey items, especially molluscs, ar e abundant. However, where a wide range of substrata, including rubble , is available, rubble is preferred because of its abundant, accessibl e prey.