SUSCEPTIBILITY OF DIFFERENT MATERIALS AND ANTIFOULING COATING TO MACROFOULING ORGANISMS IN A HIGH WAVE-ENERGY ENVIRONMENT.

Our knowledge about the interaction of materials used in aquaculture with biofouling species is largely restricted to sheltered coastal areas. Little is known about the susceptibility and specificity of different materials, or the effectiveness of antifouling (AF) coatings, to the incrustation by large biofouling species in high wave-energy environments. Since these energetic habitats are becoming increasingly targeted by the aquaculture industry, and since there is increasing concerns about the use of harmful antifouling coatings, it is urgent to boost our knowledge about biofouling risks in these environments. Here we assessed whether biofouling composition, main species, and biomass accumulation rates were different among three materials, aluminum, high-density polyethylene (HDPE), and steel A36, and at two different depths of exposed shore in central Chile. We hypothesized that either colonization was material-specific and/or the adhesion of macrofoulers to the different materials (tenacity) was sufficiently different that waves could remove them from some surfaces more than others. Additionally, we evaluated the performance of an antifouling paint widely used in aquaculture operations in Chile. All materials were colonized by macrofouling within three months of exposure, with no significant differences in either species composition, total cover, or the rate of biomass accumulation. No significant settlement of macrofouling was found on plates coated with the antifouling paint after seven months of exposure. The fast growth rates and similar composition of macrofouling suggest that the large differences in roughness and hydrophobic character among materials are not sufficient to produce differential settlement or dislodgement in these biofouling communities. The efficacy of the tested antifouling paint suggest that this paint could be used as reference when testing more environmentally-friendly coatings, such as those using biomimetic approaches. [ABSTRACT FROM AUTHOR]