Surface flocking as a possible anti-biofoulant

Abstract Fouling organisms create difficulties for aquaculturists by weighing down materials and constricting net openings. Research on anti-fouling began with toxic chemicals and has more recently moved to non-toxic methods focusing on settlement cues of invertebrates. Surface texture is one physical cue to which both invertebrate larvae and algal spores respond. Flocking is a process that makes smooth surfaces fibrous by adding electrostatically charged fibers to an adhesive coated surface. To test the effects of flocking on recruitment, polyvinyl chloride (PVC) plastic panels that were untreated, primed with adhesive, and flocked were deployed subtidally in the Westport River estuary, Westport, MA, USA for 1 month exposure periods in 1998. Species composition was determined and compared among treatments. To test for effects only on barnacle recruitment, wood panels were deployed subtidally in Clarks Cove, New Bedford, MA and PVC panels were deployed in the subtidal of Eel Pond, Woods Hole, MA; Cape Cod Canal at Massachusetts Maritime Academy, Bourne, MA; and in Point Judith Pond, RI. Flocking surfaces resulted in lower recruitment of green and brown algae, but had no effect on red algae. For invertebrates, flocking was effective at inhibiting the recruitment of encrusting animals, had no effect on stoloniferous animals, and increased the abundance of tube-building polychaetes and solitary ascidians.