## [Advantages]

(1) Improved productivity and quality due to a stable rearing environment (not affected by external factors such as climate, red tide and fish disease)

(2) Shorter aquaculture period and adjustable shipping period due to the ability to control the water temperature

(3) Minimal impact on the environment due to discharging hardly any waste water

(4) Ease of traceability

(5) Reduced work load (involving no work using fishing vessels or equipment on the sea)

(6) No locational limitation (no such restriction as the demarcated fishery right under the Fishery Act)

## [Disadvantages]

(1) High initial cost for maintaining the facility and high running cost for the use of electricity, etc.

(2) Relatively high risk of breakdown, etc. due to use of multiple equipment

(3) Risk of enormously large damage (e.g., death of all cultured fish) in the case where a virus or fish disease has been brought in or when trouble such as a power failure occurs

## [Column: Reducing red tide damage by shifting the harvest season]

O Technology has been developed to ship fish with a quality equivalent to that of fish in season during a period that is normally not the harvest season, by controlling light and water temperature and shifting the spawning period of the parent fish so as to produce seeds at an earlier timing.

O Fish species, such as yellowtail, that are shipped in or after autumn, have frequently received substantial damage from red tide, because red tide tends to occur in summer which is immediately before the shipping season. The early seed production technology, which enables shipping before the arrival of summer, is expected to reduce the scale of damage from red tide.

Source: Data from the Fisheries Research Agency

## (3) Appropriate use of wild resources

In aquaculture that relies on wild seeds, such as eel and bluefin tuna, it is essential to carry out aquaculture based on sustainable use of wild resources.

O While feed for aquaculture presently relies on raw fish and fish meal, from the viewpoint of securing feed in a stable manner, appropriate management of pelagic fish resources will be vital.

## (4) Technology development for dealing with environmental changes and maintaining wild resources

With regard to seeds of eel and bluefin tuna, it is important to accelerate development of artificial seed production technology, and to switch to full-cycle aquaculture at an early stage. Also for species such as yellowtails of which there is still an ample volume of wild seed resources at present, it is necessary to consider switching to artificial seeds, taking into account the instability of wild resources and the advantage of early shipping using early produced seeds.

O Since the demand for fishery products is currently growing worldwide, in the long term there is a need for technology to turn resources for non-human consumption into those for human consumption. One effective approach will be to make use of low-use and unused resources in waters surrounding Japan as feed for aquaculture. It is important to develop compound feed that uses a small amount of fish meal and that can be supplied at a stable price.

In order to deal with the rise in the seawater temperature, etc. in waters surrounding Japan, it is critical to create a subpopulation that is resistant to high water temperature through breeding so as to be able to continue aquaculture at the existing aquaculture sites. In addition, it will also be effective for business management and the management of wild resources to reduce the volume of feed used by creating a subpopulation that grows well with a small amount of feed.

(5) Further promotion of safe and reliable aquaculture production sought by consumers

O Safety is a fundamental matter which consumers expect producers to ensure. Consumers recognize that it is an obligation of producers to ensure the safety of their products.

☐ It is important to establish traceability and build a framework for providing necessary information to consumers.

(6) Contribution to food security, etc.

There is high likelihood that aquaculture will be expected to undertake a large share of the supply of fishery products in the future, in order to respond to the growing demand for fishery products due to such factors as the world population increase.

Japan should make contribution in that respect, making use of its abundant technology and knowledge of aquaculture.