Researcher Database
Last Updated :2024/07/25
researchmap
Profile and Settings
Profile and Settings
Name (Japanese)
SakaokaName (Kana)
KeiichiroName
200901045994379935
Achievement
Research Interests
Research Areas
Research Experience
- 2021/04 - Today Hokkaido University School of Fisheries Sciences Captain
- 2011/04 - 2021/03 Hokkaido University School of Fisheries Sciences
- 2000/04 - 2011/03 Hokkaido University School of Fisheries Sciences
- 1997 - 2000 水産学部練習船北星丸 助手
- 1997 - 2000 Research Associate
- 1994/04 - 1997/03 Hokkaido University School of Fisheries Sciences
- 1994 - Research Associate
- 1993 - 同助手（水産学部附属練習船北星丸） 助手
- 1993 - Research Associate
- 1992 - 北海道大学助手（水産学部附属練習船おしょろ丸） 助手
- 1992 - Research Associate
Education
- - 1992 Hokkaido University
- - 1992 Hokkaido University Graduate School, Division of Fisheries
- - 1991 Hokkaido University School of Fisheries Sciences
- - 1991 Hokkaido University Faculty of Fisheries
- - 1990 Hokkaido University School of Fisheries Sciences
- - 1990 Hokkaido University Faculty of Fisheries
- - 1989 Hokkaido University School of Fisheries Sciences
- - 1989 Hokkaido University Faculty of Fisheries
Published Papers
- Ren Uchida, Kenshi Kuma, Aya Omata, Satoko Ishikawa, Nanako Hioki, Hiromichi Ueno, Yutaka Isoda, Keiichiro Sakaoka, Yoshihiko Kamei, Shohgo TakagiJOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 118 (3) 1257 - 1271 2169-9275 2013/03 [Refereed][Not invited]
We measured water-column iron concentrations from west to east along 47 degrees N in the subarctic North Pacific, and in the Bering Sea. In the North Pacific dissolved Fe (D-Fe) showed surface depletion, mid-depth maxima at 1000-1500 m (west, 1.3-1.6 nM; east, 0.9-1.1 nM), and a gradual decrease with depth below 3500-4000 m depth (west, 1.1-1.4 nM; east, 0.6-0.7 nM). D-Fe and total soluble Fe (T-Fe) in deep water showed a decreasing trend eastward. The higher iron concentrations in western deep waters probably result from higher inputs of dissolved Fe through atmospheric deposition or lateral transport. In contrast, D-Fe throughout the Bering Sea showed a consistent depth regime characterized by a rapid increase with depth to mid-depths, a gradual increase with depth in intermediate water to a maximum of 1.6-1.7 nM at 1500-2250 m, and a gradual decrease with depth to 1.3-1.4 nM at 3700 m. Higher iron concentrations and deeper D-Fe maxima in the Bering Sea are likely due to higher biological productivity and greater and deeper D-Fe input from the decomposition of sinking particulate organic matter in deep water. We suggest that the higher concentrations and deeper input of D-Fe as well as PO4 and humic-type fluorescent dissolved organic matter in the Bering Sea probably results from the longer time for the accumulation of decomposition products resulting from iron supply from the organic-rich downslope sediment along the steep continental slopes and slow replacement of the deep water in the Bering Sea Basin. - Jun YAMAMOTO, Toshihiro IWAMORI, Naoki HOSHI, Takuzo ABE, Keiichiro SAKAOKA, Yoshihiko KAMEI, Shogo TAKAGI, Osamu NUMAMOTO, Yukihiro SAKA, Kazuhisa SUEOKA, Hiroki ARIMURA, Hidemi WATANABEJournal of Fisheries Technology 水産総合研究センター 5 (2) 171 - 174 1883-2253 2013/02 [Refereed][Not invited]
We developed a battery powered compact 2000m class ROV (Remotely Operated Vehicle) system with a High-Definition video camera. It does not require specialized equipment to operate. It can be operated using only general purpose equipment. This system mainly consists of a shipboard controller, a vehicle and a launcher. A thin, light optical fiber cable (diameter 9mm, length 2,500m), the primary cable, transfers control data and video images between the shipboard controller and the launcher. The secondary cable, a composite cable (diameter 14.2mm, length 50m), transfers control data and video images and supplies power to the vehicle from the six packs of lithium-ion batteries, which are mounted in the launcher. The launcher is suspended by a rope from the support ship, and the depth of the launcher is adjusted by changing the length of the rope using a general purpose rewinder.
Although initially, we had some trouble due to the launcher rope and the primary cable getting tangled, a newly-designed instrument that restricts the movement of the carabiner, and the use of a low expansion rope, facilitated smoother operation and an easier recovery of the ROV. - Ren Uchida, Kenshi Kuma, Aya Omata, Satoko Ishikawa, Nanako Hioki, Hiromichi Ueno, Yutaka Isoda, Keiichiro Sakaoka, Yoshihiko Kamei, Shohgo TakagiJournal of Geophysical Research: Oceans 118 (3) 1257 - 1271 2169-9291 2013 [Refereed][Not invited]
We measured water-column iron concentrations from west to east along 47°N in the subarctic North Pacific, and in the Bering Sea. In the North Pacific dissolved Fe (D-Fe) showed surface depletion, mid-depth maxima at 1000-1500 m (west, 1.3-1.6 nM east, 0.9-1.1 nM), and a gradual decrease with depth below 3500-4000 m depth (west, 1.1-1.4 nM east, 0.6-0.7 nM). D-Fe and total soluble Fe (T-Fe) in deep water showed a decreasing trend eastward. The higher iron concentrations in western deep waters probably result from higher inputs of dissolved Fe through atmospheric deposition or lateral transport. In contrast, D-Fe throughout the Bering Sea showed a consistent depth regime characterized by a rapid increase with depth to mid-depths, a gradual increase with depth in intermediate water to a maximum of 1.6-1.7 nM at 1500-2250 m, and a gradual decrease with depth to 1.3-1.4 nM at 3700 m. Higher iron concentrations and deeper D-Fe maxima in the Bering Sea are likely due to higher biological productivity and greater and deeper D-Fe input from the decomposition of sinking particulate organic matter in deep water. We suggest that the higher concentrations and deeper input of D-Fe as well as PO 4 and humic-type fluorescent dissolved organic matter in the Bering Sea probably results from the longer time for the accumulation of decomposition products resulting from iron supply from the organic-rich downslope sediment along the steep continental slopes and slow replacement of the deep water in the Bering Sea Basin. © 2013. American Geophysical Union. All Rights Reserved. - Jun Nishioka, Tsuneo Ono, Hiroaki Saito, Keiichiro Sakaoka, Takeshi YoshimuraJOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 116 (2) 2169-9275 2011/02 [Refereed][Not invited]
Multiyear (2003-2008) time series observations along the A line provided information on the temporal variability of the dissolved iron (diss-Fe) concentration in the Oyashio region of the western subarctic Pacific, and the data indicated that there was an annual cycle in the concentration of surface diss-Fe occurring every year. Diss-Fe was supplied into the surface water in this region every winter and supports the spring phytoplankton bloom after development of the thermocline. The diss-Fe concentration was drawn down during the phytoplankton bloom period and was depleted in summer in some water masses. Then diss-Fe increased from autumn to winter with the increasing depth of the surface mixed layer. The high diss-Fe concentrations in the surface layer in winter were controlled by mesoscale oceanic intrinsic processes, such as vertical winter mixing and horizontal Fe-rich intermediate water transport. Difference in magnitude of the winter mixing processes among different water masses caused the heterogeneous distribution of diss-Fe concentration in the surface layer. Moreover, the vertical section profiles along a cross-Oyashio transect showed the occurrence of Fe-rich intermediate water, and upward transport of materials from the intermediate water to the surface layer via tidal and winter mixing processes are important mechanisms to explain the high winter surface diss-Fe concentrations. Additionally, the substantially higher diss-Fe/NO3 ratio in the winter surface layer in this studied area other than the high-nutrient low-chlorophyll region indicates that the winter surface water in the Oyashio and the Oyashio-Kuroshio transition zone has a high potential to stimulate phytoplankton growth. - Nishioka J, Ono T, Saito H, Sakaoka K, Yoshimura TJournal of Geophysical Research 116 (C2) C02021 0148-0227 2011 [Refereed][Not invited]
- Jun Nishioka, Tsuneo Ono, Hiroaki Saito, Keiichiro Sakaoka, Takeshi YoshimuraJournal of Geophysical Research: Oceans 116 (2) 2169-9291 2011 [Refereed][Not invited]
Multiyear (2003-2008) time series observations along the A line provided information on the temporal variability of the dissolved iron (diss-Fe) concentration in the Oyashio region of the western subarctic Pacific, and the data indicated that there was an annual cycle in the concentration of surface diss-Fe occurring every year. Diss-Fe was supplied into the surface water in this region every winter and supports the spring phytoplankton bloom after development of the thermocline. The diss-Fe concentration was drawn down during the phytoplankton bloom period and was depleted in summer in some water masses. Then diss-Fe increased from autumn to winter with the increasing depth of the surface mixed layer. The high diss-Fe concentrations in the surface layer in winter were controlled by mesoscale oceanic intrinsic processes, such as vertical winter mixing and horizontal Fe-rich intermediate water transport. Difference in magnitude of the winter mixing processes among different water masses caused the heterogeneous distribution of diss-Fe concentration in the surface layer. Moreover, the vertical section profiles along a cross-Oyashio transect showed the occurrence of Fe-rich intermediate water, and upward transport of materials from the intermediate water to the surface layer via tidal and winter mixing processes are important mechanisms to explain the high winter surface diss-Fe concentrations. Additionally, the substantially higher diss-Fe/NO3 ratio in the winter surface layer in this studied area other than the high-nutrient low-chlorophyll region indicates that the winter surface water in the Oyashio and the Oyashio-Kuroshio transition zone has a high potential to stimulate phytoplankton growth. Copyright © 2011 by the American Geophysical Union. - Nishioka J, Ono T, Saito H, Sakaoka K, Yoshimura T, MatobaAGU Fall Meeting Abstracts 1 0331 2010 [Refereed][Not invited]
- Saori Kitayama, Kenshi Kuma, Eri Manabe, Koji Sugie, Hyoe Takata, Yutaka Isoda, Kenji Toya, Sei-Ichi Saitoh, Shohgo Takagi, Yoshihiko Kamei, Keiichiro SakaokaJournal of Geophysical Research: Oceans 114 (8) 2169-9291 2009/08/08 [Refereed][Not invited]
[1] Dissolved Fe in the western and central North Pacific Ocean was characterized by surface depletion, middepth maxima and, below that, a slight decrease with depth similar to the vertical distributions of nutrients, apparent oxygen utilization, Fe(III) hydroxide solubility, and humic-type fluorescence (H-flu) intensity. Dissolved Fe concentrations ([D-Fe], < 0.22-μm fraction) in the deep water column were one-half lower in the central region (0.3-0.6 nM) than the western region (0.5-1.2 nM) although the Fe(III) solubility ([Fe(III)sol], < 0.025-μm fraction) levels and distributions in deep waters were almost the same between both regions with middepth maxima (∼0.6 nM) at 500-1500-m depth range and then a gradual decrease to ∼0.3 nM at 5000-m depth. Higher [D-Fe] than [Fe(III)sol] in the deep water column of the western region results from the higher production of dissolved Fe from the decomposition of sinking particulate organic matter in the western region than the central region because of the high atmospheric and/or lateral Fe inputs in the western region. Similarity between [D-Fe] level and [Fe(III)sol] value at each deep water depth in the central region may be attributed to [D-Fe] being nearly in the solubility equilibrium with Fe(III) hydroxide in seawater. Strong linear correlation between [D-Fe] and H-flu intensity in the central region and relatively similar linear relationships between [Fe(III)sol] and H-flu intensity in the western and central regions are the first confirmation that humic-type fluorescent dissolved organic matter may be responsible for [D-Fe] in the deep water column as natural organic ligands complexing with Fe(III). Copyright 2009 by the American Geophysical Union. - Saori Kitayama, Kenshi Kuma, Eri Manabe, Koji Sugie, Hyoe Takata, Yutaka Isoda, Kenji Toya, Sei-ichi Saitoh, Shohgo Takagi, Yoshihiko Kamei, Keiichiro SakaokaJOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 114 2169-9275 2009/08 [Refereed][Not invited]
Dissolved Fe in the western and central North Pacific Ocean was characterized by surface depletion, middepth maxima and, below that, a slight decrease with depth similar to the vertical distributions of nutrients, apparent oxygen utilization, Fe(III) hydroxide solubility, and humic-type fluorescence (H-flu) intensity. Dissolved Fe concentrations ([D-Fe], <0.22-mu m fraction) in the deep water column were one-half lower in the central region (0.3-0.6 nM) than the western region (0.5-1.2 nM) although the Fe(III) solubility ([Fe(III)sol], <0.025-mu m fraction) levels and distributions in deep waters were almost the same between both regions with middepth maxima (similar to 0.6 nM) at 500-1500-m depth range and then a gradual decrease to similar to 0.3 nM at 5000-m depth. Higher [D-Fe] than [Fe(III)sol] in the deep water column of the western region results from the higher production of dissolved Fe from the decomposition of sinking particulate organic matter in the western region than the central region because of the high atmospheric and/or lateral Fe inputs in the western region. Similarity between [D-Fe] level and [Fe(III)sol] value at each deep water depth in the central region may be attributed to [D-Fe] being nearly in the solubility equilibrium with Fe(III) hydroxide in seawater. Strong linear correlation between [D-Fe] and H-flu intensity in the central region and relatively similar linear relationships between [Fe(III)sol] and H-flu intensity in the western and central regions are the first confirmation that humic-type fluorescent dissolved organic matter may be responsible for [D-Fe] in the deep water column as natural organic ligands complexing with Fe(III). - KITAYAMA Saori, KUMA Kenshi, MANABE Eri, SUGIE Koji, TAKATA Hyoe, ISODA Yutaka, TOYA Kenji, SAITOH Sei-ichi, TAKAGI Shohgo, KAMEI Yoshihiko, SAKAOKA KeiichiroJournal of Geophysical Research. Supplement 114 (C8) C08019 0148-0227 2009 [Refereed][Not invited]
- The summer hydrographic surveys of the southeastern Bering Sea shelf and shelf break, carried out by T?S Oshoro-maruMizobata K, S. Saitoh, K. Kuma, T. Meguro, Y. Kajiwara, S. Takagi, Y. Kamei, K. SakaokaKAIYO MONTHLY 50 116 - 126 2008 [Not refereed][Not invited]
- WAGAWA Taku, ISODA Yutaka, SAITOH Nana, AZUMAYA Tomonori, SAKAOKA Keiichiro, Taku Wagawa, Yutaka Isoda, Nana Saitoh, Tomonori Azumaya, Keiichiro Sakaoka, Graduate School of Fisheries Science Hokkaido University, Graduate School of Fisheries Science Hokkaido University, Factory of Fisheries Hokkaido University, Factory of Fisheries Hokkaido UniversityOceanography in Japan 日本海洋学会 15 (3) 267 - 281 2186-3105 2006 [Refereed][Not invited]
北部北太平洋には亜寒帯前線と亜寒帯境界の間として定義される移行領域(Transitional Domain: TD)が存在し,TDを南北に横切るように170°Eに沿って天皇海山列が存在している。本研究では155°E,165°E,170°E,175.5°E,180°線における長期間の海洋観測データを解析し,TDにおける水塊構造が天皇海山列を境界に大きく変化していることを明らかにした。天皇海山列の東西海域ではTDを明確に特定できるのに対して,天皇海山列上においてTDはしばしば存在せず,南から北に向かって亜熱帯水から亜寒帯水に急激に変化する水塊前線を形成していた。さらに,TDにおける東向き輸送に沿って,水塊は西から東に向かって亜寒帯水から亜熱帯水へ急激に変化していた。TD付近に存在する強い東向きの傾圧流は,天皇海山列上の43°N付近(推古海山と仁徳海山の間)を通過した後,北側にシフトする。この傾圧流の強弱や分布位置は経年変動したが,北側にシフトする傾向は何れの年においても同じであった。傾圧流を挟んだ西側と東側のTDで起こる水塊の変化は,亜表層において特徴的な水塊である中央モード水が重い密度帯から軽い密度帯へ変化することに起因していた。すなわち,傾圧流の北側へのシフトと中央モード水の密度帯の変化は密着に関連していることが示唆された。Spatial distributions of baroclinic flow and water mass in the "Transition Domain" (TD), defined between the Subarctic Front and Subarctic Boundary in the northern North Pacific, were investigated through analysis of long-term hydrographic data taken in 155°E, 165°E, 170°E, 175.5°E, and 180° meridians. Along the 170°E meridian, the Emperor Seamounts is located across the TD in a strict north to south direction. Although the TD could be clearly detected on both sides of the Emperor Seamounts, it frequently disappeared and had a remarkable watermass front, i.e., abrupt and meridional, changing from subtropical to subarctic water masses, in the location of the Emperor Seamounts. Furthermore, along the eastward transport of the TD, an abrupt zonal change from subarctic to subtropical water took place. In each year, the estimated eastward baroclinic flow around the TD suggested a shift to the north after passage through the trench of the Emperor Seamounts around 43°N (between Suiko Seamount and Nintoku Seamount), although small year-to-year changes were shown in its intensity and horizontal distribution. This shift in flow might explain the above zonal water mass change in the TD. It was also shown that the density of the "Central Mode Water", formed at the sea surface mixed layer in winter, was gradually lighter from the west to the east. - H Takata, K Kuma, Y Saitoh, M Chikira, S Saitoh, Y Isoda, S Takagi, K SakaokaGEOPHYSICAL RESEARCH LETTERS 33 (2) L02613 - L02613 0094-8276 2006/01 [Refereed][Not invited]
Labile dissolved Fe (< 0.22 mu m) in the western (165 degrees E) and eastern (165 degrees W) North Pacific Ocean had nutrient- and apparent oxygen utilization (AOU)- like profiles characterized by surface depletion and deep enrichment ( 5 - 3000 m depth). Dissolved Fe concentrations in the deep-water column at the mid-latitudes were approximately one-half lower in the eastern region (0.5 - 0.8 nM) than in the western region ( 0.8 - 1.3 nM) although the dissolved Fe concentrations in the surface mixed layer in both regions were extremely depleted to 0.1 - 0.2 nM. Surprisingly, the labile particulate Fe concentrations (<=similar to 0.1 nM, total dissolvable Fe minus labile dissolved Fe) throughout the water column at low latitudes in the eastern region were extremely lower than those (similar to 0.5 - 1 nM) in the western region. It is suggested that the low Fe levels in the eastern mid-latitude oceanic region are primarily due to the lower atmospheric Fe supply in the eastern region. - 橋本 洋平, 磯田 豊, 大西 広二, 坂岡 桂一郎海の研究 14 (4) 513 - 525 0916-8362 2005 [Refereed][Not invited]
- 山口 篤, 目黒 敏美, 梶原 善之, 高木 省吾, 亀井 佳彦, 坂岡 桂一郎水産海洋研究 68 (4) 0388-9149 2004/11/10 [Not refereed][Not invited]
- H Takata, K Kuma, S Iwade, Y Yamajyoh, A Yamaguchi, S Takagi, K Sakaoka, Y Yamashita, E Tanoue, T Midorikawa, K Kimura, J NishiokaMARINE CHEMISTRY 86 (3-4) 139 - 157 0304-4203 2004/05 [Refereed][Not invited]
Sources of natural Fe(III)-complexing organic ligands which control vertical distributions of Fe(III) hydroxide solubilities [Fe(III) solubility, < 0.025 mum] and labile dissolved Fe (< 0.22 mum) concentrations were studied at the subarctic and subtropical surface waters (5-300-m depth) in the northwestern North Pacific Ocean during June 2002. High Fe(III) solubility values (0.71.3 nM) were observed at the depth of high chlorophyll a (Chl a) concentrations in the surface mixed layer with no strong correlation between Fe(III) solubility and size-fractionated Chl a concentrations. However, a significant correlation was found between Fe(Ill) solubility values and heterotrophic bacteria abundance at 5 - 100-m depth in the subarctic coastal water. The high Fe(III) solubility observed in the surface mixed layer is probably due to the production of natural Fe(III)-complexing organic ligands, such as siderophores, which were possibly released by specific phytoplankton or bacteria species. Higher Fe(III) solubility values than the labile dissolved Fe concentrations in the surface waters indicate that natural Fe(III)-complexing organic ligands are in excess of labile dissolved Fe concentrations. The Fe(III) solubility levels appeared to increase with depth in mid-depth waters (100-300-m depth), especially in the subarctic waters, in association with higher iron levels (labile dissolved Fe and dissolvable Fe concentrations), nutrient concentrations and humic-type fluorescence intensity. The relatively strong linear correlations between labile dissolved Fe concentrations or Fe(III) solubility values and humic-type fluorescence intensity in mid-depth waters suggest that the labile dissolved Fe concentrations and Fe(III) solubility in mid-depth waters are primarily associated with humic-type fluorescent organic matter produced through the oxidative decomposition and transformation of sinking biogenic organic matter. Humic-type fluorescent organic matter (i.e., marine dissolved humic substances) may thus account for a significant fraction of the Fe(III)-complexing organic ligands, which control Fe(III) solubility and labile dissolved Fe concentrations in mid-depth waters. (C) 2004 Elsevier B.V. All rights reserved. - AMANO Haruna, FUKADA Haruhisa, FUJITA Toshiaki, KOBAYASHI Naoto, SAKAOKA Keiichirou, HARA AkihikoAquaculture Science 日本水産増殖学会 52 (3) 293 - 300 0371-4217 2004 [Refereed][Not invited]
Lipovitellin (Lv), the major yolk protein product derived from vitellogenin (Vg), was purified from ovaries of bigeye tuna, Thunnus obesus, using a hydroxylapatite column chromatography followed by gel filtration. The apparent molecular mass of native Lv was-300 kDa, while its corresponding subunit mass estimated by SDS-PAGE was-105 kDa. Western blotting, using a rabbit antiserum raised against purified tuna Lv (a-tLv), revealed specific reaction with a polypeptide (-210 kDa) present only in serum from female bigeye tuna, with no reaction in male serum. This suggested that the -210 kDa polypeptide represented a Vg monomer. As a result, a simultaneous two-site chemiluminescent immunoassay (CLIA) was developed to quantify tuna Vg using acridinium-labeled a-tLv F (ab') 2. The assay range, expressed as the relative concentration of Lv standard, was 0.97 to 1000 ng/ml. The dilution curves of female serum and egg extracts were parallel to the standard curve of purified Lv. The coefficient variations of either intra-or inter-assay were less than 10%. The CLIA had cross-reactivity with serum from female bluefin and yellowfin tuna, and also from female yellowtail. Vg was detected in the serum from three of seven female bigeye tuna caught off the Hawaiian islands, but not detected in the male bigeye tuna. - ODATE Tsuneo, SAKAOKA Keiitiro, KAJIWARA Yoshiyuki, IMAI Keiri, KOBAYASHI Naoto, MEGURO Toshimi, FUKUTI MitsuoBulletin of the Plankton Society of Japan 日本プランクトン学会 46 (2) 134 - 142 0387-8961 1999 [Refereed][Not invited]
- S. Takagi, Y. Sakurai, Y. Kamei, T. Miyoi, K. Sakaoka, N. ShigaBulletin - Hokkaido University, Faculty of Fisheries 48 (1-2) 13 - 28 1997Oceanographic conditions and distribution of pelagic nekton during the summer and fall in 1995 and 1996 in the northwestern North Pacific Ocean were examined. The gillnet survey and hydrographic observations were conducted along 155°E longitude from 32° to 44° N latitude. The Kuroshio Front located at the northern boundray of the Kuroshio Extension current was found near 38°N in the summer and fall. In the summer, warm water from the Kuroshio was found in the Subarctic Domain. The warm water was associated with an increase in chlorophyll-a and zooplankton. In the fall, Intermediate Cold Water occured in the Subarctic Domain, and concentration of nutrients and chlorophyll-a were high in fine structure. The distribution of pelagic nekton differed in the summer and fall. In the summer, the dominant species north side of the front were pink salmon Oncorhynchus gorbuscha and chum salmon O.keta. The dominant species around the front was flying squid Ommastrephes bartramii. In the fall, the dominant species in subtropical waer were flying squid and dolphin Coryphaena hippurus. The distribution of flying squid was controlled by the Kuroshio Front. In the summer, the front corresponded to the boundary between LL-size group (north side) and the small-size group (south side). In the fall, the front corresponded to the boundary between immature (north side) and mature (south side) squid.
MISC
- N. Hoshi, K. Sakaoka, Y. Kajiwara, M. Ohwada, T. Sato, K. Imai, Y. Inagaki, S. Takagi NPAFC Doc. 1692.The North Pacific Anadromous Fish Commission (NPAFC) 2017/04 [Not refereed][Not invited]
- Tatsuta, N, H. Imamura, K. Nakaya, T. Kawai, T. Abe, K. Sakaoka, S. Takagi, M. Yabe Memoirs of the Faculty of Fisheries Sciences, Hokkaido University 56- (1) 1 -64 2014/05 [Not refereed][Not invited]
A taxonomic examination of 3,108 specimens of mesopelagic fishes, collected around the Ogasawara Islands in December 2010 by a beam trawl net operated from the T/S Oshoro-maru, Hokkaido University, Japan, resulted in the recognition of 99 species representing 34 families and 65 genera. Descriptions are provided for all species, two of them〔 a stomiid Eustomias braueri Zugmayer, 1911 and linophrynid Haplophryne mollis (Brauer, 1902)〕 being new records for Japan. Three species, a stomiid Eustomias sp., trachipterid Desmodema sp. and oneirodid Oneirodes sp., could not be identified at the species level. - 西岡純, 的場澄人, 小埜恒夫, 齊藤宏明, 坂岡桂一郎 月刊海洋 43- (11) 648 -654 2011/11/01 [Not refereed][Not invited]
- 山本潤, 岩森利弘, 星直樹, 坂岡桂一郎, 高木省吾, 沼本修, 阪幸宏, 有村博紀, 渡邉日出海 日本水産学会大会講演要旨集 2011- 10 2011/09/28 [Not refereed][Not invited]
- Jun Nishioka, Tsuneo Ono, Hiroaki Saito, Keiichiro Sakaoka, Takeshi Yoshimura JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS 116- 2011/04 [Not refereed][Not invited]
- 西岡純, 小埜恒夫, 齊藤宏明, 坂岡桂一郎, 芳村毅 日本海洋学会大会講演要旨集 2010- 73 2010/08/25 [Not refereed][Not invited]
- 栗原縁, 渡部千種, 高木省吾, 亀井佳彦, 坂岡桂一郎, 星直樹, 阿部拓三, 桜井泰憲 水産海洋学会研究発表大会講演要旨集 2010- 19 2010 [Not refereed][Not invited]
- 渡部千種, 栗原縁, 高木省吾, 亀井佳彦, 坂岡桂一郎, 星直樹, 阿部拓三, 桜井泰憲 水産海洋学会研究発表大会講演要旨集 2010- 89 2010 [Not refereed][Not invited]
- Results of 2009 Salmon Research Cruises of the Oshoro maru.North pacific Anadromouse Fish Commition Documents (Doc.1226) Doc.1226 2010 [Not refereed][Not invited]
- 2008 T/V Oshoro-maru Salmon Research CruisesNorth pacific Anadromouse Fish Commition Documents 1158- 17 2009 [Not refereed][Not invited]
- 2007 T/V Oshoro-maru Salmon Research CruisesNorth Pacific AnadromouseFish Commition Documents 1088- 25 2008 [Not refereed][Not invited]
- Results of 2006 Salmon Research Cruise of the Oshoro maruNorth Pacific AnadromouseFish Commition Documents 1021- 16 2007 [Not refereed][Not invited]
- Results of 2005 Salmon Research Cruise of the Oshoro MaruNorth Pacific Anadromous Fish Commission 940- 1 2006 [Not refereed][Not invited]
- 大西 広二, 坂岡 桂一郎 海洋 37- (10) 736 -741 2005/10
- 山口篤, 横井裕, 栗山圭輔, 亀井佳彦, 坂岡桂一郎, 池田勉 日本海洋学会大会講演要旨集 2005- 193 2005/09/05 [Not refereed][Not invited]
- 高田兵衛, 久万健志, 西岡純, 芳村毅, 緑川貴, 木村完, 山口篤, 高木省吾, 坂岡桂一郎 日本海洋学会大会講演要旨集 2005- 149 2005 [Not refereed][Not invited]
- Results of 2004 Salmon Research Cruise of the Oshoro MaruNorth Pacific Anadromous Fish Commission 840- 1 2005 [Not refereed][Not invited]
- 山口 篤, 目黒 敏美, 梶原 善之, 高木 省吾, 亀井 佳彦, 坂岡 桂一郎 水産海洋研究 68- (4) 269 -269 2004/11/10
- 山口篤, 今尾史義, 佐野史和, 池田勉, 坂岡桂一郎, 亀井佳彦 日本海洋学会大会講演要旨集 2004- 299 2004/03/26 [Not refereed][Not invited]
- 山条喜宣, 久万健志, 高田兵衛, 山口篤, 斉藤雪美, 高木省吾, 坂岡桂一郎 日本海洋学会大会講演要旨集 2004- 175 2004/03/26 [Not refereed][Not invited]
- Wagawa Taku, Isoda Yutaka, Takagi Shogo, Sakaoka Keiichirou Bulletin of Fisheries Sciences, Hokkaido University 55- (1) 23 -33 2004 [Not refereed][Not invited]
- Results of 2003 Salmon Research Cruise of the Oshoro maruNorth Pacific Anadromous Fish Commission 748- 1 -15 2004 [Not refereed][Not invited]
- Results of 2002 Salmon Research Cruise of the Oshoro MaruNorth Pacific Anadromous Fish Commission 663- 1 2003 [Not refereed][Not invited]
- YONETA Kunisaburo, MEGURO Toshimi, KAJIWARA Yoshiyuki, SAKAOKA Keiiciro Bulletin of Fisheries Sciences, Hokkaido University 53- (1) 51 -55 2002 [Not refereed][Not invited]
- The 2000 International cooperative Salmon research Cruse of The Oshoro MaruNorth Pacific Anadromous Fish Commission 547- 1 2001 [Not refereed][Not invited]
- Stock Abundance and Fish Size of Pacific Salmon in the North Pacific Ocean, 1998North Pacific Anadromous Fish Commission. 323- 1 1998 [Not refereed][Not invited]
- Takagi shogo, Sakurai Yasunori, Kamei Yoshihiko, Myoi Takako, Sakaoka Keiichiro, Shiga Naonobu Bulletin of the Faculty of Fisheries,Hokkaido University 48- (1/2) 13 -28 1997 [Not refereed][Not invited]