Introduced Marine Aquatic Invaders - a field guide

What damage they do

During 1999, black striped mussel (Mytilopsis sp.) was found in three marinas in Darwin Harbour. Recognised internationally as a significant marine pest, the black striped mussel has had massive economic and ecological impacts in south eastern India, where it fouls almost all intertidal and sublittoral structures, habitats and vessels. Early detection in Darwin provided a unique opportunity for the eradication of this introduced pest.

Photo CSIRO Marine Research

Not all marine species introduced into a new country or state become pests. In fact, not all of them will survive the move.

Thankfully, most of the marine animals and plants that establish self-sustaining populations in Australian waters are relatively harmless. However, some invaders are tough, aggressive types that achieve their pest status by preying on native species, competing with local species for food and space, and altering the marine habitat to suit themselves. Current knowledge suggests that one in every six introduced marine species will establish itself as a pest.

In addition to changing the marine environment, introduced marine species have the potential to damage recreational fisheries, the aquaculture industry, commercial fisheries and the shipping industry.

Introduced species may dominate marine communities and wipe out native species, some of which are the basis of recreational and/or commercial fisheries. Many introduced species are encrusting organisms and will smother native species and attach themselves to any artificial structure in the water, such as long-lines used in aquaculture, vessels, jetties and stormwater pipes.