Abstract
In the coastal area from the Sea of Japan to the Seto Inland Sea, measures are being taken to release arti ficial fish juveniles into the sea and reflect them in fishing catch in order to improve the resource productivity of valuable reef fish such as Redspotted groupers (Epinephelus akaara) and Oblong rockfish (Sebastes oblongus). However, the yield is only about 1% due to feeding damage by natural enemy organisms after release and lack of proper habitat (reef area). Then, it has been demonstrated that the yield when released into structures such as artificial reefs with a protective and nurturing function developed by the authors maintains a higher value than that of natural release. However, it was difficult to evaluate the accurate yield due to the lack of quantitative data on the survival and return of fish juveniles.
In this research, we have developed a method to discriminate between Redspotted groupers (Epinephelus akaara) and fish that are natural enemies by AI. Also, we have proposed quantitative evaluation method of the retention rate of rock fish juveniles in the shelter, the amount of juveniles returning to the artificial reefs and efficiently release for juveniles.
