CONCLUSION, REFERENCES

 

CONCLUSION

Over 90 percent of market demand for bluefin tuna comes from Japan, although important markets in Southeast Asia and the United States of America are emerging. There is an increasing global demand for seafood, a corresponding increase in demand for premium quality tuna for the sushi and sashimi market and a growing need to respond to the decline of most wild BFT fisheries worldwide. These are driving the development of reliable technologies for large-scale production of juvenile tuna, for both commercial food production and fisheries restocking. As these technologies improve, the economics of full cycle farming should also improve, and quite possibly result in changes in the market structure for hatchery-produced fish.

There would be benefits for fisheries, aquaculture and farm managers if BFT could be measured by underwater stereo-video without the trauma caused by capture and handling. In Australia, improved underwater measurements are currently being used with this system. The most significant disadvantage is the delay in the availability of information to farm managers and fisheries/aquaculture management agencies, due to the manual post-processing of video images (Harvey et al., 2003). Similar studies are also being carried out in Italy and hopefully in the near future the quality of the biometric data will help to improve stock assessment which is the basis for an effective management of the resource.

In view of the extensive use of bait fish, the high feed conversion ratios and related farm management problems (e.g. purchasing, transporting, storage, and distribution of bait fish and environmental effects), the industry must intensify studies on artificial feed in order to mitigate the problems associated with the used of bait fish. In the meantime, however, there is a need to standardize control systems to ensure baitfish quality and avoid the introduction of potential pathogens. In order to ensure total transparency of the industry and traceability of traded tuna, farmers need to adopt and follow best farming practices throughout the production process.
Furthermore, urgent management actions are required to mitigate the impact of illegal fishing as it is estimated that 30 percent of total BFT catches derive from IUU fishing. These fishing activities must be controlled and eliminated and the industry must comply with the quotas agreed for the conservation of the wild stock. It is also recommended that the catch data from “recreational fishing” is recorded to curb illegal sport fishing of tuna.
The development of a specific bluefin tuna code of conduct should be shared by fishers, farmers and importers to ensure the implementation of all management regulations. This could also be a tool for the collection and reporting of bluefin tuna capture-based aquaculture data.

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