Operation and Management of Areas.

Aquaculture production in areas is coordinated through a number of different routes. Farms in a FMA have stocking and treatment plans that are coordinated through a FMAg, if this is in place, or less formally if farms have individual FMS. Areas have moved towards synchronised fallowing, which is now widespread and recommended under the Code of Good Practice.3 All farms within an area should wait until the last farm in that area is empty before restocking.

This is an important tool for disease control and in the management of sea lice. In the event of not ifiable disease, synchronised fallowing may be legally enforced across the affected area of the DMA.
Treatment for sea lice is often coordinated, as untreated farms can act as refuges for lice that allow infection levels to re-increase rapidly. However, treatment presents logistical challenges and so may be applied to neighbouring sites over a short period rather than be strictly synchronised.
A trend that has improved coordination within areas has been a movement towards single operator FMAs, with companies strategically exchanging sites so that one company owns all the sites in a particular FMA.

This allows coordination to be achieved more easily.
Some FMA boundaries have also extended closer to DMA boundaries, for example the merger of several FMAs in southeast Shetland after ISA spread across the FMA boundaries. The new FMA in this case now matches the local DMA boundaries. If FMA and DMA activities occur within the same boundaries this makes for easier management. In some areas, DMAs have been split and separated by the strategic closure of sites to form smaller areas that can be managed more easily.
Movements of fish, equipment and personnel may be prevented both in and out of areas with notifiable disease (except movements to authorised biosecure processing plants). Sites that are not themselves infected may be covered by these movement restrictions.
This area approach reduces the risk of spread and can be effective in containing infection to a limited area. Local processing plants, with locally operating vessels, may also reduce risk of longdistance spread of infection.
Locational Guidelines Categorisation of sea lochs into 1 (no increase in biomass permitted), 2 (limited potential for expansion of the sector) and 3 (greatest expansion potential) are applied at both the development consenting and licensing processes to restrict any increases in maximum permitted biomass of farmed finfish in areas which are thought to be close to capacity. Estimates of the nutrient enhancement and impacts of benthic enrichment of the seabed are updated quarterly on the basis of changes to biomass consent under CAR, and water body categories in the guidelines are updated as required.
Sea lice chemotherapeutant discharges (bath treatments) are also logged by the various regulators (SEPA for treatments in cages, Marine Scotland Licensing for treatments from well boats) and in the event of multiple planned discharges in the same water body predicted to exceed Environmental Quality Standards (EQS), either regulator may restrict use of the compound in that water body.