Understanding how pelagic fish assemblages reorganize in response to oceanographic variability is central to fisheries oceanography. We analyzed long‐term purse‐seine logbook data (1994–2022) from the East China Sea and Sea of Japan to link multivariate assemblage structure with species‐specific occurrence and habitat responses. Seasonal nonmetric multidimensional scaling (nMDS) ordinations followed by k ‐means clustering reve...

The Japanese sardine, Sardinops melanostictus , is a major fishery resource in the Sea of Japan (SOJ) and East China Sea (ECS); however, recent research on suitable habitats and migration patterns of this fish in these seas is lacking. We aimed to identify the oceanographic conditions (temperature, chlorophyll‐ a concentration, and sea surface height anomaly) suitable for Japanese sardines and predict migration patterns based...

Recruitment of Japanese jack mackerel ( Trachurus japonicus ) has been decreasing continuously since 2000 in the Pacific coastal waters of Japan. The reasons and mechanisms for this phenomenon are still unclear. Particle‐tracking experiments were performed using a data assimilation model to elucidate the effect of a current system on the transportation processes of T. japonicus from the main spawning ground in the southern Eas...

This study examined characteristics of near-inertial internal waves (NIWs) associated with the background mesoscale field near the Tsushima Warm Current. Observational stations off Sado Island were visited recurrently to assess spatiotemporal changes of fine-scale and microscale properties of seawater. Also, NIWs were inspected in terms of relative vorticity and total strain in surface geostrophic motion. During summer expedit...