Use of extract from adults of the triangle barnacle, Balanus trigonus, for reducing fouling in mussel farms

Many millions of dollars are lost each year in the green-lipped mussel (Perna canaliculus) aquaculture industry in New Zealand due to fouling with the triangle barnacle (Balanus trigonus). A novel approach to reducing the numbers of barnacle cyprids settling on the cultured mussels would be to promote their settlement onto sacrificial materials placed in the vicinity of the mussels. An initial field experiment found settlement plates treated with an extract from adult B. trigonus (AE) increased the settlement of conspecific cyprids by 4.6 times. Subsequently, AE-treated material placed near cultured mussels reduced the overall number of barnacles on the mussels by around 4.5 times and increased the number of barnacle-free mussels by almost a third. These results suggest this novel approach to using natural settlement cues to remove barnacle cyprids from the vicinity of valuable shellfish may have potential in controlling these major biofouling pests in shellfish aquaculture.