How can tunicates become fouling organisms on ships?

Tunicates become fouling organisms on ships primarily due to their life cycle and sessile nature. During their brief larval stage, these chordates are motile and actively search for a suitable solid surface to inhabit. Once a larva locates an appropriate substrate—such as a ship's hull, wharf pile, or rock—it attaches itself using three anterior adhesive papillae.123

Following this attachment, the organism undergoes metamorphosis into a sessile adult. Because these benthic forms naturally grow on solid surfaces in marine environments, they readily colonize the hulls of ships, where they remain fixed as they mature.1243