To clarify the early life history of pointhead flounder Cleisthenes pinetorum, spatial distribution, diel vertical migration and transportation of pelagic larvae were investigated in Funka Bay and its vicinity off Hokkaido Island in summer during 2001-2003. Larvae were mainly collected by simultaneously horizontal hauls with MTD closing nets in the transition water mass (32.4-33.6 in salinity) between Summer Funka Bay Water (<32.4) originating from Oyashio Water and Tsugaru Warm Water (>33.6 and>6°C). The younger stage larvae without yolk-sac (stage A and stage B) collected by MTD hauls occurred in the layers of 7.4-18.2°C, but not in those of 18.3-20.7°C. In day and night, stages A and B larvae were concentrated in the 20-40 m depth layers where copepod nauplii as the initial food item for them were less abundant than 1-10 m layers. A small scale of nocturnal ascent was observed in the advanced larvae inclusive of notochord flexion stage (stages C-F grouped), and they were collected in the 30-40 m and 20-40 m layers in day and night, respectively. Tidal vertical migration was not observed. Pelagic larvae would be transported from the offshore spawning ground to the nursery area in the bay with the transition water mass.

The feeding habits of pointhead flounder Cleisthenes pinetorum larvae were investigated in and near Funka Bay, Hokkaido Island during 10-20 August 2001. As the larvae grew, the principal prey shifted from copepod nauplii (especially, Oithona similis and Pseudocalanus newmani) as the initial food item to copepodites and an appendicularia Oikopleura sp. Nauplii of Microsetella sp. were abundant in the sampling area, but few were eaten by the larvae. The number of prey in the larval digestive tracts increased from 08:55 and peaked near sunset, suggesting the larvae are visual day feeders. Nauplii concentrations in the water varied geographically, but the number of nauplii in the larval digestive tracts did not vary. Pointhead flounder larvae in the first feeding stage might not starve in and near Funka Bay in August 2001.

Mark and recapture experiment of young-of-the-year ocellate puffers (≦500g BW) were carried out in the Kii Channel by longline fishermen of Tokushima Prefecture during December in 1990 to March in 1991 and during November in 1991 to March in 1992. Two hundred ocellate puffers were recaptured in the Seto Inland Sea, Pacific Ocean, East China Sea, and Sea of Japan. Most of the puffers but one migrated to the western waters of Seto Inland Sea. They migrated southward to Tosa Bay on the Pacific coast during February to March when water temperature at 20 m depth in the Seto Inland Sea was below 10°C, In other months they migrated westward through the Seto Inland Sea. Only one ocellate puffer migrated eastward and recaptured in Kumano-Nada Sea. These results indicated that the migration range of ocellate puffers tagged in the Kii Channel extends from the waters around Shikoku Island to the East China Sea including waters of western Sea of Japan. This ocellate puffer population seems to be independent from the one in Ise Bay and Mikawa Bay on the Pacific coast of central Japan.