Amphibalanus amphitrite is a medium-sized barnacle, 10–20 mm in basal diameter, with distinctive purple-brown vertical stripes on its white shell plates. It cements permanently to surfaces using one of the strongest biological adhesives known — a proteinaceous glue that cures underwater and resists forces exceeding 1 MPa. The species tolerates temperatures from 12 °C to 30 °C and salinities from 10 to 40 ppt, giving it an enormous geographic range across the Mediterranean, the eastern Atlantic, and the Black Sea. It also thrives in brackish estuaries and harbour environments.
In Mediterranean aquaculture, striped barnacles are a persistent year-round fouler. Cyprid larvae detect surface biofilms and can commit to settlement within hours of a new structure being submerged. Once established, barnacle clusters create rough, rigid surfaces that increase drag by 50–100 % and degrade the structural integrity of nylon netting over repeated cleaning cycles. Barnacles also provide crevice habitat for parasites and smaller fouling organisms, compounding the problem. The cost calculator helps quantify the long-term expense of managing hard-fouling species like this one.
Copper-based anti-fouling coatings reduce settlement by 70–90 % during the first 12–18 months but eventually leach below effective concentrations. Silicone foul-release coatings work differently — barnacles still attach but bond weakly and detach under current or cleaning pressure, making removal easier and less damaging to nets. Scraping established A. amphitrite off cage frames requires force and inevitably scars the underlying surface. Compare all available anti-fouling approaches, and see how this species relates to the northern acorn barnacle in the organisms database.
Control Methods
Anti-fouling coatings Manual scraping Silicone foul-release coatings