Marine Produce Australia: Cone Bay Barramundi Aquaculture ...

Figure 5.3 Narrative decision scheme for applying the EQC for sediment quality
5.4 Contingency management
In the event that an EQS is exceeded, management will be undertaken to reduce the effect of
contaminant(s) and restore environmental quality to comply with the specified level of
ecological protection. Examples of management steps may include:
5.4.1 Fallowing of sea-cages
Fallowing (or movement) of sea-cages has been shown to be a highly effective method for
reducing the point source impacts of aquaculture, particularly to sediments. Studies on the
effects of fallowing indicate that the chemistry of sediments on impacted sites will return to
original state after stock are removed. Time taken for redox readings to return to normal is
site dependant and influenced by sediment particle size, and local flushing and scouring
rates. Generally redox readings return to pre-stocking levels within a few months to a year
of fallowing (e.g. MacLeod et al. 2002; Forrest et al. 2007).
Oceanica: Marine Produce Australia: Cone Bay Barramundi Aquaculture, Environmental Monitoring & Management Plan 43