LIFE MODES IN MOLLUSCAN ASSEMBLAGES OF THE LOWER WACCAMAW FORMATION (PLEISTOCENE) OF SNAKE ISLAND PIT IN NORTH CAROLINA
GSU bivalves were dominated by individuals that were unattached (80%), actively mobile (83%), and infaunal (84%) followed by immobile (10%), byssally attached (11%), and epifaunal (13%) bivalves. Feeding categories for bivalves were represented mostly by individuals that were suspension feeders (80%) with chemosymbiotic (9%) and other deposit feeders (8%) less common. Gastropods were comprised mostly of individuals categorized as predatory carnivores (75%) followed by suspension feeders (10%) and herbivores (9%). Life modes have not yet been assigned to all individuals in these samples as 8% of gastropods and 4% of bivalves are still being identified.
Similar patterns for bivalves were found in the UNCW sample, in that most individuals were unattached (68%), actively mobile (66%), and suspension feeders (97%). However, epifaunal and infaunal life habits were evenly represented (51% vs. 49%); very few bivalves were deposit feeders (3%). Bivalves immobile (31%) via cementation (31%) were more common than byssally attached individuals (1%). The distribution of gastropod individuals is represented by increased suspension feeders (53%) and fewer predatory carnivores (45%) compared to the GSU samples. Taxa responsible for differences in the UNCW sample include elevated Crepidula and Conradostrea.