(Development of WISE Program to foster AI Professionals
for Marine Industries)

Report on Completion of internship at the Japan Agency for Marine-Earth Science and Technology (JAMSTEC)
(MITSUYU, Course of Marine Policy and Management)

　From November 17, 2025 to January 30, 2026, I participated in an internship at the Yokohama Institute of the Japan Agency for Marine-Earth Science and Technology (JAMSTEC) for a total of 13 days.
　
　During the internship, I worked on improving a migration model for Pacific chub mackerel. In particular, I focused on refining the southward migration model to reproduce the arrival of fish in the Hyuga-nada area, which had been difficult to simulate in previous studies. By adjusting the model structure and parameters and running simulations under several scenarios, I obtained migration trajectories such as those shown in the figure below. These simulations were conducted using JAMSTEC's large-scale high-performance computing system, which was a very valuable experience.

　Through this internship, I deepened my understanding of the concept of individual-based modeling (a modeling approach that represents a population as particles and describes their behavior and responses to the ocean environment). I also learned how to implement the model in Fortran and how to use basic command-line operations in a server environment. Furthermore, the year-to-year variation in the number of particles arriving in the Hyuga-nada area corresponded well with historical changes in Pacific chub mackerel catches in Miyazaki Prefecture. These results are scheduled to be presented at the Marine Biology Symposium 2026.

　I hope to apply the knowledge and experience gained from this internship to my future research and contribute to the development of stock assessment models that incorporate migration dynamics. Finally, I would like to express my sincere gratitude to the JAMSTEC staff for hosting and supporting my internship.

(Migration trajectories obtained from the southward migration simulation)

MITSUYU, 1st year master's student, Course of Marine Policy and Management