Factors that influence vessel biofouling and its prevention and management

The Department of Agriculture, Water and the Environment (the department) leads the effective management of biofouling risk by minimising the likelihood of entry and establishment of exotic marine species transferred by vessel biofouling. Biofouling on internationally plying vessels is a significant vector for the translocation of exotic marine species (Molnar et al. 2008; Davidson et al. 2018). These species may become invasive and cause significant impact to the economy, environment and the way of life in regions where they establish. More than 250 exotic marine species have already been introduced to Australia (MESA 2019a).
International ship movements have facilitated the translocation of multiple species and often entire assemblages of tens to hundreds of species between disparate bioregions (Hewitt et al. 2011). All vessels have some degree of biofouling, even those which may have been recently cleaned or had a new application of an anti-fouling system. The biofouling process begins within the first few hours of a ship's immersion in seawater and is a continual process that is influenced by both environmental conditions (e.g. salinity, temperature) and the unique operational profile of a vessel. The development and maintenance of ship-specific documents that (i) detail the planning of biofouling management measures in biofouling management plans and that (ii) record the implemented actions in record books is the internationally accepted best-practice approach to reducing biosecurity risks associated with biofouling (IMO 2011). Maintaining low fouling levels provides economic benefits such as fuel savings and an associated reduction in greenhouse gas emissions (Abbott et al. 2000; Selim et al. 2017). It also reduces the likelihood of encountering an exotic marine species that can become invasive and cause harm (Bell et al. 2011).