Marine Produce Australia: Cone Bay Barramundi Aquaculture ...

3. Environmental Objectives
3.1 Best-practice marine farming
Best practice environmental management depends on knowledge of the potential effects of
sea-cage aquaculture together with an understanding of the host environment, including the
extent and variety of benthic habitats (particularly BPPHs), the characteristic water quality
and the extent of local biodiversity. Utilising this knowledge, proactive management
strategies have been developed to maximise farming efficiency and to minimise the likelihood
of adverse environmental impacts. Management strategies have been (and continue to be)
developed by MPA through consultation with scientists, regulators and other marine farm
operators. Further information on best practice marine farming can be read in the
Department of Fisheries, Environmental Code of Practice for the Management of Western
Australia’s Marine Finfish Industry, and The Scottish Executive (ASFA) 2003, which MPA has
used as the basis for best practice marine farming.
A key consideration in best practice marine farming is management of fish feeds, such that
feed waste is minimised. The key proactive feed-wastage management strategies to be
employed by the proponent are outlined below:
� The company strategy is to minimise wasted feed through controlling overfeeding;
� Stocking densities will be managed to maintain optimum biological stocking rates to
promote fish health and growth, and to reduce the impact of fish and feed waste on the
seabed in the immediate vicinity of each sea cage;
� Fallowing practices will be used as required to facilitate restoration of sediment quality
under the sea-cages so as to comply with the specified level of ecological protection;
� Feed cameras and or pellet sensors will be used during fish feeding to determine optimum
feed input rates and correct stop feeding signals, thereby reducing wasted feed; and
� All farm fish mortalities will be removed from the sea-cages twice weekly.
3.2 Best-practice environmental management
The EMMP has been designed according to the framework developed by the National Water
Quality Management Strategy (NWQMS): the Environmental Quality Management Framework
(EQMF). The Government of Western Australian has endorsed the state-wide implementation
of the EQMF on a priority basis (Government of Western Australia 2003, 2004).
Consistent with the NWQMS, the EMMP has adopted a structured approach to management.
MPA has agreed to maintain the EVs and EQOs (see Table 1.1) through adherence to
appropriate EQG and EQS. The EQG and EQS criteria have been set in the context of EQO1:
Maintenance of Ecosystem Integrity. It is noted that risks posed by this aquaculture proposal
are such that if the EQO for the EV Ecosystem Health is met, then all other EVs will also be
protected.
3.3 Environmental performance indicators/criteria
EQG and EQS have been developed in the context of the Ecological Protection Zones specified
in Schedule 1 of Ministerial Statement 798.
Environmental Quality Guidelines (EQG): are threshold numerical values or narrative
statements, that if met, indicate there is a high degree of certainty that the associated
environmental quality objective has been achieved. If the guideline is not met, there is
uncertainty as to whether the associated environmental quality objective has been achieved
and a more detailed assessment against the EQS is triggered.
Environmental Quality Standards (EQS): are threshold values or narrative statements
that indicate a level beyond which there is a significant risk that the associated environmental
quality objective has been not been achieved. The response would normally focus on
identifying the cause (or source) of the exceedance and then reducing loads of the
contaminant of concern (i.e. source control) and may also require in situ remedial work to be
undertaken. EQS are generally equivalent to the water quality objectives described in
ANZECC/ARMCANZ (2000).
12 Oceanica: Marine Produce Australia: Cone Bay Barramundi Aquaculture, Environmental Monitoring & Management Plan