Introductions of seaweeds : accidental transfer pathways and mechanisms

Macroalgae are a significant component of historic and modern invasions, with association to a wide variety of transport mechanisms. These transport mechanisms pose specific constraints on the ways by which species can be taken up, transported and released into a new environment. Currently operating transport mechanisms for marine macroalgae are either associations with intentional introductions (translocations for aquaculture, aquarium or live seafood trade) or accidental introductions (mainly as hull-fouling). A number of potential management options exist, including the development of international instruments and regional agreements. The development of treatment options for hull fouling, the most significant and poorly managed transport mechanism for macroalgae, is of urgent need. Our current ability to identify which species are likely to invade next is limited. However, an examination of the synergies between species’ functional traits, transport constraints, and recipient community attributes will likely provide possible options in the future.