Limit, cease or prohibit ballast water exchange in specific areas
Overall effectiveness category No evidence found (no assessment)
Number of studies: 0
Background information and definitions
Non-native, invasive and other problematic species can impact on native subtidal benthic invertebrate species through predation, competition for resources (food & space), contamination (for pathogens and diseases), or hybridization (through reproduction) (Molnar et al. 2008; Bishop et al. 2010). Ballasting is the process by which sea water (ballast water) is taken in and out of the ship when the ship is at port or at sea. Ballast water can therefore contain species from one location taken-up during water intake, which are then accidentally released in a new environment during de-ballasting (water release). Ballast water is one of the major processes of introduction of non-native, invasive and problematic species (Barry et al. 2008; Hewitt 2003; Hewitt et al. 2004; Molnar et al. 2008). Limiting, ceasing, or prohibiting ballast water exchange in specific areas may potentially help prevent the introduction, the establishment and the spread of non-native species and potentially invasive species. Limiting introduction, establishment and spread of such species could be achieved by setting new zone boundaries where ballasting is allowed, setting timing where risk is reduced, or setting limits on the number of ships allowed to ballast at any given time.
Related evidence is summarised under “Threat: Invasive and other problematic species, genes and diseases – Treat ballast water before exchange”.
Barry S.C., Hayes K.R., Hewitt C.L., Behrens H.L., Dragsund E. & Bakke S.M. (2008) Ballast water risk assessment: principles, processes and methods. ICES Journal of Marine Science, 65, 121–131.
Bishop M.J., Krassoi F.R., McPherson R.G., Brown K.R., Summerhayes S.A., Wilkie E.M. & O’Connor W.A. (2010) Change in wild-oyster assemblages of Port Stephens, NSW, Australia, since commencement of non-native Pacific oyster (Crassostrea gigas) aquaculture. Marine and Freshwater Research, 61, 714–723.
Hewitt C.L. (2003). Marine biosecurity issues in the world oceans: global activities and Australian directions. Ocean Yearbook, 17, 193–212.
Hewitt C.L., Campbell M.L., Thresher R.E., Martin R.B., Boyd S., Cohen B.F., Currie D.R., Gomon M.F., Keough M.J., Lewis J.A., Lockett M.M., Mays N., McArthur M.A., O’Hara T.D., Poore G.C.B., Ross D.J., Storey M., Watson J.E. & Wilson R.S. (2004) Introduced and cryptogenic species in Port Phillip Bay, Victoria, Australia. Marine Biology, 144, 183–202. Molnar J.L., Gamboa R.L., Revenga C. & Spalding M.D. (2008) Assessing the global threat of invasive species to marine biodiversity. Frontiers in Ecology and the Environment, 6, 485–492.