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Hokkaido University Collection of Scholarly and Academic Papers >
Graduate School of Fisheries Sciences / Faculty of Fisheries Sciences >
北海道大学水産科学研究彙報 = Bulletin of Fisheries Sciences, Hokkaido University >
第57巻 第3号 >
Food Availability for First-feeding Walleye Pollock (Theragr chalcogramma) Larvae during Winter in and Near Funka Bay, Hokkaido, Japan, as Inferred from Copepod Nauplii Abundance
| Title: | Food Availability for First-feeding Walleye Pollock (Theragr chalcogramma) Larvae during Winter in and Near Funka Bay, Hokkaido, Japan, as Inferred from Copepod Nauplii Abundance |
| Authors: | Nakatani, Toshikuni Browse this author →KAKEN DB | | Ohshima, Masakane Browse this author | | Yoshida, Kie Browse this author | | Sasaki, Shiho Browse this author | | Shirakawa, Norihiro Browse this author | | Yamamoto, Naohiro Browse this author |
| Keywords: | Oithona similis | | Oithona nauplii | | Reproduction | | Food conditions | | First-feeding walleye pollock | | Theragra chalcogramma | | Larvae | | Funka Bay | | Hokkaido | | Japan |
| Issue Date: | Dec-2007 |
| Publisher: | 北海道大学大学院水産科学研究院 |
| Journal Title: | 北海道大学水産科学研究彙報 |
| Journal Title(alt): | BULLETIN OF FISHERIES SCIENCES, HOKKAIDO UNIVERSITY |
| Volume: | 57 |
| Issue: | 3 |
| Start Page: | 25 |
| End Page: | 35 |
| Abstract: | To clarify the relationship between the food availability for pollock larvae and the hydrographic conditions in Funka Bay, horizontal distributions of water temperature, salinity and Oithona nauplii (main food for larval pollock) were investigated in winter from 2001 to 2003 in and near the bay. In January 2001 and 2003, the Oyashio coastal cold-water mass and the Tsugaru warm-water mass were co-distributed in the bay and its mouth region, but in January 2002, the Oyashio coastal cold-water mass has already exchanged with the Tsugaru warm-water mass. The median abundances of Oithona nauplii in January of each year were not different significantly. In January 2003, the density of female O. similis (main producer of Oithona nauplii) was higher in the Oyashio coastal cold-water mass than in the Tsugaru warm-water mass, while the densities of Oithona N1 in the Oyashio coastal cold-water mass and the Tsugaru marm-water mass were almost identical. These data indicate that the high activity of the individual reproduction is occurred in the Tsugaru warm water. From the results, it is considered that the warm-water temperature and the reproduction of O. similis in the Tsugaru warm-water mass in winter in Funka Bay support the larval feeding success. |
| Type: | bulletin (article) |
| URI: | http://hdl.handle.net/2115/32484 |
| Appears in Collections: | 北海道大学水産科学研究彙報 = Bulletin of Fisheries Sciences, Hokkaido University > 第57巻 第3号
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