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). Commercial vessels are major means of trans-oceanic transport of non-native species, while recreational boating is known to facilitate the local spread once in a new environment (Campbell & Hewitt 1999; Clarke et al. 2011; Hewitt et al. 2004). Non-native species can become attached to the hard surfaces of ships and boats, including the hull, anchor, and chain, and be accidentally transported from one location to another (Campbell & Hewitt 1999; Hewitt et al. 2004). Regular cleaning of hulls, anchors and chains can potentially reduce the risk of introduction to new location, and as such reduce the risk non-native species pose to native subtidal benthic invertebrates.
Evidence related to the cleaning of surfaces is summarised under “Threat: Invasive and other problematic species, genes and diseases – Clean anthropogenic platforms, structures or equipment”.
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.
Campbell M.L. & Hewitt C.L. (1999) Vectors, shipping and trade. Pages 45–60 in: Hewitt C L, Campbell ML, Thresher RE, Martin RB (eds.). The Introduced Species of Port Phillip Bay, Victoria. Centre for Research on Introduced Marine Pests, CSIRO Marine Research, Hobart.
Clarke Murray C., Pakhomov E.A. & Therriault T.W. (2011) Recreational boating: a large unregulated vector transporting marine invasive species. Diversity and Distributions, 17, 1161–1172.
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.