Impacts of invasive species introduced through the shipping industry

Summary form only. Environmental challenges or ocean policy invasive species also called exotics, nonnative species, or nonindigenous species have been introduced inadvertently into many marine waters by the shipping industry. These species are transported as fouling organisms on ship hulls and in the ballast water of transient ships. Ship fouling can result in the transport of organisms across oceans as well as between coastal ports. While most ship fouling is associated with invertebrates and plants, some evidence suggests that fish also accompany a heavily fouled vessel. The degree of fouling on ships, fishing vessels, and private boats has been reduced through the use of antifoulant paints. Prior to their use, about one-third of the introduced species in Australia are believed to have been transported via fouling organisms on the hulls of overseas shipping vessels. Some fouling still occurs today, especially in situations where antifouling paint cover is chipped, difficult to apply, or otherwise ineffective. Invasive species can have adverse ecological and economic impacts by causing declines in native species through habitat alteration or by out-competing native species, and thus, permanently reducing biological diversity. Mariculture and commercial and recreational fishing can also be adversely affected because the new invading species are predators, competitors, and parasites, and some cause or carry disease. Finally, some invasive species, such as toxic dinoflagellates and cholera-causing bacteria, can affect human health