Breaking the Ice: From Antarctic Biofouling Colonization to Plastisphere-Mediated Ecological Risks

A synthesis of current knowledge on the composition and dynamics of marine biofouling, and its role in altering the ecological setting of Southern Ocean benthic communities, is presented here. Current research on biofouling focuses on two main drivers of change: the introduction of invasive marine species (IMS) via hull biofouling, and plastic debris, and the dispersal of antibiotic-resistant bacteria through the development of microbial biofilms, often mediated by the persistence of artificial substrates. Despite the logistical difficulties of conducting experimental studies in such a harsh polar environment, macrofouling communities have been found to display high levels of complexity, a feature also observed within microbial communities. Macrofouling assemblages are dominated by bryozoans and spirorbid polychaetes; however, colonization by these communities is extremely slow compared to temperate regions. The emerging role of plastic-associated microbial biofilms (plastisphere) as novel ecological niches in Antarctic waters is also addressed. These microbial assemblages may act as reservoirs and potential dispersal vectors of antibiotic resistance, raising new concerns regarding ecosystem health under increasing anthropogenic pressure and climate-driven environmental changes.