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カキ養殖業と漁師を営む家庭に生まれ、幼いころから海や魚と親しんできました。海のことが好きで、高校・大学ではヨット部に所属しました。海や生物の勉強をするため広島大学　生物生産学部に入学し、大学院生物圏科学研究科の海野徹也准教授のもとで研究を行ってきました。
約10年間お世話になった広島大学を2017年11月に離れ，日本学術振興会の海外特別研究員という制度を利用して現在はカリフォルニア大学ロサンゼルス校の生態進化生物学部のBarber Labにて研究を続けています。将来は、日本を代表する海洋生物の研究者になる予定です。

Marine resources contribute to food security and adequate nutrition for a global human population, providing protein to about 3 billion people with at least 15 percent of their average per capita animal protein intake. Generally, fish populations can be sustainably harvested if the method of harvest does not destroy the reproductive potential of species. However, global finfish stocks have been declined over the past 40 years, possibly due to the overfishing and environmental change such as rising water temperature.

In such a status, the amount of squid catch increased 4 times over the past 40 years in order to satisfy an increasing global demand for protein. In addition, squid abundance has also increased despite to marine environmental changes. Squids have special biological characteristics including rapid growth and short life span, which allow them to adapt to changing environmental conditions more quickly than other marine species.

My target species Sepioteuthis cf. lessoniana, one of the most widely distributed neritic squids, is occurred in coastal waters throughout the Indo-West Pacific region including Japan to Australia and New Zealand, and from Hawaii to East Africa, north to the Red Sea and south to Madagascar, where one of the most commercially important species with the highest market value. Accurate information on the stock structures is necessary to the effective management of any commercially exploited species, especially the oval squid characterized by highly sensitive to changing marine environment with shallow water habitat and egg-laying to the substrate. In addition, this squid produces the least number of eggs in this family.

The primary objective of this study is to determine the structure of the oval squid stock around Japan. Because of lack of the clear and apparent morphological difference among the three species of Sepioteuthis, our DNA approach successfully detected three distinct species and genetic population structures of two Sepioteuthis species, Sepioteuthis sp. 1 Red squid and sp. 2 White squid, which were dominant fishery targets around Japan. Our results suggested that co-occurrence of these species was found in Pacific area. In addition, Red squid and White squid showed difference in spawning depth and dispersal ability. Therefore, spawning support using artificial structure should consider the depth. For example, Red squid spawned egg deeper than that of White squid. Also, Red squid showed higher levels of genetic separation among the sampling locations, which suggested fishery management should be conducted in each local fishery community.

In conclusion, my study provides crucial information for sustainable harvest of not only oval squid but also other economically important squid. It would contribute the food security and adequate nutrition for a global human population expected to reach 9.7 billion by 2050