Biofouling can impact many aspects of aquaculture. In finfish culture, biofouling is limited to equipment while in seaweed and shellfish culture, fouling is not only on equipment but on culture species. The physical damage of biofouling often leads to a susceptibility to diseases, parasites, and predation.
Two types of marine species that are known fouling species that were indirectly introduced to the Caribbean region are the Asian paddle crab (Charybdis japonica) and the Asian green mussel (Perna Viridis). The Asian paddle crab may carry the White Spot Syndrome virus which can affect crustacean mariculture, indirectly altering trophic levels and impacting biodiversity through predation. While the Asian green mussel fouls ships, aquaculture infrastructure, and hydro-technical constructions.
A recent study looked at the Caribbean spider crab as a candidate for biofouling removal. The spider crabs were placed on a heavily fouled unoccupied sea station offshore of Eleuthera in the Bahamas. Large crabs were able to remove between 40% of fouling organisms in two weeks and 90% after four weeks. This experiment demonstrated how effective spider crabs were at the removal of biofouling, than divers. In conclusion, spider crabs can be a solution for controlling biofouling on aquaculture cages, making them both environmentally and economically friendly.
Presently, Caribbean countries sans St. Vincent and the Grenadines and Dominica, have signed onto the Ballast Water Management Convention of the International Maritime Organization. This treaty is to prevent the spread of non-indigenous species, pathogens, and aquatic organisms.
Source:
UNEP – Impacts of Biofouling in Marine Aquaculture
IMO – Common Hull Fouling Invasive Species
Caribbean Invasives Policy Brief No. 4 – Prevention and Management of Marine Invasive Alien Species in the Caribbean
Article – Potential use of the Caribbean spider crab for biofouling removal on marine aquaculture cages