Heat/moisture‐treated potato and corn starch granules were observed by microscopy and X‐ray diffraction patterns were obtained. A scanning electron microscope (SEM) photograph of the cross section of the heat/moisture‐treated potato and corn starch granules showed a large hollow area about 1/3 of the diameter at the center of the starch granules and a layered structure resembling growth rings. From the X‐ray diagrams it was confirmed that heat/moisture‐treatment caused an alteration from the B‐type in the direction an A‐type structure in potato, whereas corn starch did not change and maintained an A‐type structure. The enzymatic digestibility of heat/moisture‐treated starch was found to be less resistant than that of native starch.

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Tracking the movement of migratory fish is of great importance for efficient conservation, although this has been technically difficult to achieve in small fish to which artificial tags cannot be attached. We show that migration history can be reproduced by combining high‐resolution otolith stable oxygen isotope ratio (δ18O) analysis and numerical simulation. High‐precision micromilling and microvolume carbonate analysing systems had the remarkable capability of extracting the otolith δ18O profiles with 10–30 days resolution. Furthermore, reasonable movements were reproduced by searching the routes consistent with the otolith δ18O profile, using an individual‐based model with random swimming behaviour. This method will be a valuable alternative to tagging and electronic loggers for revealing migration routes in early life stages, thereby providing crucial information to understand population structures and the environmental cause of recruitment variabilities, and to validate and improve fish movement models.

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A two-dimensional individual-based fish movement model coupled with fish bioenergetics was developed to simulate the observed migration and growth of Japanese sardine (Sardinops melanostictus) in the western North Pacific. In the model, derived from the observed ocean-environmental data as the driving force, fish movement was adapted as a kinesis behavior. The model successfully simulated the observed transport patterns during the egg and larval stages and the northward migrations during the juvenile stage in 2005, 2006 and 2007. The model results showed that both temperature during the larval stage in the Kuroshio Extension and the prey availability during the early juvenile stage in the Kuroshio-Oyashio transitional area are important factors for growth of Japanese sardine. In autumn, the observed juvenile sardine were mainly distributed in the subarctic water region off the Kuril Islands, which is an area (158-165°E, 43-47°N) with a high chlorophyll-a (Chl-a) concentration. The model reproduced the fish distribution, which has a high density in this region. The high Chl-a concentration area in autumn may contribute to increasing the survival rate of Japanese sardine by cascading up the food chain, from the high primary production, and is an important habitat for recruitment success of Japanese sardine.