Researcher basic information

• 水産学学士, 北海道大学

• https://researchmap.jp/read0166825?lang=en

• 200901045994379935

• 海洋観測技術
• 水産学一般

• Life Science, Aquatic bioproduction science

• Bachelor's degree program, School of Fisheries Sciences

Research activity information

• Application of satellite remote sensing data for predicting the occurrence of hypoxia at the seabed: a case study in Funka Bay, Japan
  Hiroto Abe; Akihiro Sasaki; Hiroji Onishi; Atsushi Ooki; Tetsuya Takatsu; Takahiro Iida; Naoto Kobayashi; Keiichiro Sakaoka; Tsubasa Chujo; Soya Sakuma; Shintaro Ohno
  International Journal of Remote Sensing, 1, 22, Informa UK Limited, 09 Jan. 2026
  Scientific journal
• Water column iron dynamics in the subarctic North Pacific Ocean and the Bering Sea
  Ren Uchida; Kenshi Kuma; Aya Omata; Satoko Ishikawa; Nanako Hioki; Hiromichi Ueno; Yutaka Isoda; Keiichiro Sakaoka; Yoshihiko Kamei; Shohgo Takagi
  JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 118, 3, 1257, 1271, Mar. 2013, [Peer-reviewed]
  English, Scientific journal
• Development of a Battery Powered Compact 2000m Class ROV System and Its Method of Operation
  Jun YAMAMOTO; Toshihiro IWAMORI; Naoki HOSHI; Takuzo ABE; Keiichiro SAKAOKA; Yoshihiko KAMEI; Shogo TAKAGI; Osamu NUMAMOTO; Yukihiro SAKA; Kazuhisa SUEOKA; Hiroki ARIMURA; Hidemi WATANABE
  Journal of Fisheries Technology, 5, 2, 171, 174, 水産総合研究センター, Feb. 2013, [Peer-reviewed]
  Japanese, Scientific journal, 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.
• Water column iron dynamics in the subarctic North Pacific Ocean and the Bering Sea
  Ren Uchida; Kenshi Kuma; Aya Omata; Satoko Ishikawa; Nanako Hioki; Hiromichi Ueno; Yutaka Isoda; Keiichiro Sakaoka; Yoshihiko Kamei; Shohgo Takagi
  Journal of Geophysical Research: Oceans, 118, 3, 1257, 1271, Blackwell Publishing Ltd, 2013, [Peer-reviewed]
  English, Scientific journal
• Oceanic iron supply mechanisms which support the spring diatom bloom in the Oyashio region, western subarctic Pacific
  Jun Nishioka; Tsuneo Ono; Hiroaki Saito; Keiichiro Sakaoka; Takeshi Yoshimura
  JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 116, 2, Feb. 2011, [Peer-reviewed]
  English, Scientific journal
• Oceanic iron supply mechanisms which supprt the spring diatom bloom in the Oyashio region, western subarctic pacific
  Nishioka J; Ono T; Saito H; Sakaoka K; Yoshimura T
  Journal of Geophysical Research, 116, C2, C02021, American Geophysical Union (AGU), 2011, [Peer-reviewed]
  English, Scientific journal
• Oceanic iron supply mechanisms which support the spring diatom bloom in the Oyashio region, western subarctic Pacific
  Jun Nishioka; Tsuneo Ono; Hiroaki Saito; Keiichiro Sakaoka; Takeshi Yoshimura
  Journal of Geophysical Research: Oceans, 116, 2, Blackwell Publishing Ltd, 2011, [Peer-reviewed]
  English, Scientific journal
• The annual cycle of surface iron and the source of iron supporting the spring diatom bloom in the Oyashio region, western subarctic Pacific
  Nishioka J; Ono T; Saito H; Sakaoka K; Yoshimura T; Matoba
  AGU Fall Meeting Abstracts, 1, 0331, 2010, [Peer-reviewed]
• Controls on iron distributions in the deep water column of the North Pacific Ocean: Iron(III) hydroxide solubility and marine humic-type dissolved organic matter
  Saori Kitayama; Kenshi Kuma; Eri Manabe; Koji Sugie; Hyoe Takata; Yutaka Isoda; Kenji Toya; Sei-Ichi Saitoh; Shohgo Takagi; Yoshihiko Kamei; Keiichiro Sakaoka
  Journal of Geophysical Research: Oceans, 114, 8, Blackwell Publishing Ltd, 08 Aug. 2009, [Peer-reviewed]
  English, Scientific journal
• Controls on iron distributions in the deep water column of the North Pacific Ocean: Iron(III) hydroxide solubility and marine humic-type dissolved organic matter
  Saori Kitayama; Kenshi Kuma; Eri Manabe; Koji Sugie; Hyoe Takata; Yutaka Isoda; Kenji Toya; Sei-ichi Saitoh; Shohgo Takagi; Yoshihiko Kamei; Keiichiro Sakaoka
  JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 114, Aug. 2009, [Peer-reviewed]
  English, Scientific journal
• Controls on iron distributions in the deep water column of the North Pacific Ocean: Iron(III) hydroxide solubility and marine humic-type dissolved organic matter.
  KITAYAMA Saori; KUMA Kenshi; MANABE Eri; SUGIE Koji; TAKATA Hyoe; ISODA Yutaka; TOYA Kenji; SAITOH Sei-ichi; TAKAGI Shohgo; KAMEI Yoshihiko; SAKAOKA Keiichiro
  Journal of Geophysical Research. Supplement, 114, C8, C08019, 2009, [Peer-reviewed]
• Hydrographic Structural Change in the Transition Domain around the Emperor Seamounts
  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 University
  Oceanography in Japan, 15, 3, 267, 281, 日本海洋学会, 2006, [Peer-reviewed]
  Japanese, 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.
• Comparing the vertical distribution of iron in the eastern and western North Pacific Ocean
  H Takata; K Kuma; Y Saitoh; M Chikira; S Saitoh; Y Isoda; S Takagi; K Sakaoka
  GEOPHYSICAL RESEARCH LETTERS, 33, 2, L02613, L02613, Jan. 2006, [Peer-reviewed]
  English, Scientific journal
• Temperature Minima in the Gulf of Alaska in the Summer from 1994 to 2002
  HASHIMOTO Yohei; ISODA Yutaka; ONISHI Hiroji; SAKAOKA Keiichiro; Yohei Hashimoto; Yutaka Isoda; Hiroji Onishi; Keiichiro Sakaoka; Graduate School of Fisheries Science Hokkaido University; Graduate School of Fisheries Science Hokkaido University; Graduate School of Fisheries Science Hokkaido University; Factory of Fisheries Hokkaido University
  Oceanography in Japan, 14, 4, 513, 525, 日本海洋学会, 2005, [Peer-reviewed]
  Japanese, Suga et al. (2003)は180°断面で観測される亜表層の水温極小水の起源がベーリング海西部の冬季混合層にあることを示した。アラスカ湾においても水温極小が存在しており, この水塊の存在は水深100～150mに形成される強い塩分(密度)躍層によって保たれている。このアラスカ湾の水温極小水の起源を明らかにするために, 9年間(1994-2002年)継続して行なわれた145°W断面の水温・塩分資料を解析した。その結果, 180°断面と145°W断面で観測される水温極小の水塊特性の違いが明らかになった。次に, 冬季海面水温と145°W断面で観測された水温極小のコア水温の経年変動解析から, 145°W断面の水温極小はアラスカ湾付近における冬季の大気海洋相互作用により, その場で形成されている可能性を示した。145°W断面では上述の水温極小以外に, 塩分躍層以深にもう一つの水温極小がみられた。この水温極小は26.7σ_θよりも重い密度帯で微細な水温逆転構造をもち, 西向きの流れ場の中に多く存在する傾向がある。Suga et al. (2003) found that subsurface temperature minimum water observed along 180° meridian originated in the winter mixed layer of the western Bering Sea. In the Gulf of Alaska, the permanent halocline at the depth of 100～150m dominates the density stratification, supporting a similar temperature minimum. We analyzed repeated hydrographic data along the 145°W meridian for 9 years (1994～2002), in order to examine the origin of temperature minimum water in the Gulf of Alaska. We have pointed out the difference in water characteristics of temperature minima between 180° and 145°W sections. Close correlation between the temporal variations of winter sea surface temperature and the lowest temperature observed along 145°W meridian suggests that temperature minimum water can be formed around the Gulf of Alaska by wintertime air-sea interaction. We found another temperature minimum water below the above mentioned subsurface temperature minimum. It is accompanied by many fine temperature inversions in the density range greater than 26.7σ_θ and is mainly found within the westward deep-flow area.
• Spatial variability of iron in the surface water of the northwestern North Pacific Ocean
  H Takata; K Kuma; S Iwade; Y Yamajyoh; A Yamaguchi; S Takagi; K Sakaoka; Y Yamashita; E Tanoue; T Midorikawa; K Kimura; J Nishioka
  MARINE CHEMISTRY, 86, 3-4, 139, 157, May 2004, [Peer-reviewed]
  English, Scientific journal
• Development of a Simultaneous Chemiluminescent Immunoassay for Bigeye Tuna, Thunnus obesus, Vitellogenin
  AMANO Haruna; FUKADA Haruhisa; FUJITA Toshiaki; KOBAYASHI Naoto; SAKAOKA Keiichirou; HARA Akihiko
  Aquaculture Science, 52, 3, 293, 300, Japanese Society for Aquaculture Science, 2004, [Peer-reviewed]
  Japanese, 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.
• Characteristics of standard methods of Norpac net towing in the high latitude sea area II. Overtowing under rough sea conditions and estimation of zooplankton abundance
  ODATE Tsuneo; SAKAOKA Keiitiro; KAJIWARA Yoshiyuki; IMAI Keiri; KOBAYASHI Naoto; MEGURO Toshimi; FUKUTI Mitsuo
  Bulletin of the Plankton Society of Japan, 46, 2, 134, 142, 日本プランクトン学会, 1999, [Peer-reviewed]
  Japanese

• Results of 2019 Salmon Research by the Oshoro maru
  Taichi Sato; Keiichiro Sakaoka; Naoki Hoshi; Keiri Imai; Maki Ohwada; Kenji Oguma; Kouki Sawada; Shogo Takagi, Apr. 2020
  English
• Results of 2016 Salmon Research by the Oshoro maru
  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), Apr. 2017
  English, Report research institution
• Taxonomy of mesopelagic fishes collected around the Ogasawara Islands by the T/S Oshoro-Maru.
  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, May 2014
  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., Faculty of Fisheries Sciences, Hokkaido University, English, Introduction research institution
• 潮汐混合とオホーツク海・ベーリング海の物理・化学・生物過程―白鳳丸KH09‐4航海・おしょろ丸・クロモフ2006/2007シンセシス―親潮域・混合域の鉄濃度の季節的変動を支配するプロセス―海洋循環・潮汐混合・大気ダスト―
  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, 01 Nov. 2011
  Japanese
• バッテリー駆動による2000m級小型ROVの開発と運用
  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, 28 Sep. 2011
  Japanese
• Oceanic iron supply mechanisms which support the spring diatom bloom in the Oyashio region, western subarctic Pacific (vol 116, C04007, 2011)
  Jun Nishioka; Tsuneo Ono; Hiroaki Saito; Keiichiro Sakaoka; Takeshi Yoshimura, JOURNAL OF GEOPHYSICAL RESEARCH-OCEANS, 116, Apr. 2011
  English, Others
• Fe^*を用いた親潮域中層におけるオホーツク海からの鉄移送量の評価
  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, 25 Aug. 2010
  Japanese
• 2008‐2009年夏季ベーリング海東部における魚類稚仔の分布と海洋環境との関係
  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
  Japanese
• 夏季セントローレンス島南海域に分布するホッキョクダラの生物学的特性
  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
  Japanese
• Results of 2009 Salmon Research Cruises of the Oshoro maru.
  North pacific Anadromouse Fish Commition Documents, Doc.1226, Doc.1226, 2010
• 2008 T/V Oshoro-maru Salmon Research Cruises
  North pacific Anadromouse Fish Commition Documents, 1158, 17, 2009
• The summer hydrographic surveys of the southeastern Bering Sea shelf and shelf break, carried out by T?S Oshoro-maru
  Mizobata K; S. Saitoh; K. Kuma; T. Meguro; Y. Kajiwara; S. Takagi; Y. Kamei; K. Sakaoka, KAIYO MONTHLY, 50, 116, 126, 2008
  Japanese
• 2007 T/V Oshoro-maru Salmon Research Cruises
  North Pacific AnadromouseFish Commition Documents, 1088, 25, 2008
• Results of 2006 Salmon Research Cruise of the Oshoro maru
  North Pacific AnadromouseFish Commition Documents, 1021, 16, 2007
• Results of 2005 Salmon Research Cruise of the Oshoro Maru
  North Pacific Anadromous Fish Commission, 940, 1, 2006
• 北太平洋亜寒帯海域におけるArgoデータの利用 (総特集 Argoの現状と未来)
  大西 広二; 坂岡 桂一郎, 海洋, 37, 10, 736, 741, Oct. 2005
  海洋出版, Japanese
• 2003年,2004年夏季の北太平洋亜寒帯域における動物プランクトン群集の東西比較
  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, 05 Sep. 2005
  Japanese
• 北西部北太平洋亜寒帯と親潮域における鉄,カドミウム及び栄養塩の挙動
  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
  Japanese
• Results of 2004 Salmon Research Cruise of the Oshoro Maru
  North Pacific Anadromous Fish Commission, 840, 1, 2005
• 西部北太平洋における浮魚類 : 北星丸データより
  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, 10 Nov. 2004
  水産海洋学会, Japanese
• 北太平洋の表層~漸深層までの動物プランクトンバイオマス165°Eと165°Wの東西比較
  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, 26 Mar. 2004
  Japanese
• 北部北太平洋表層における鉄の東西比較
  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, 26 Mar. 2004
  Japanese
• Transition Domain on 155°E Meridian in 2002 and 2003
  Wagawa Taku; Isoda Yutaka; Takagi Shogo; Sakaoka Keiichirou, Bulletin of Fisheries Sciences, Hokkaido University, 55, 1, 23, 33, 2004
  Hokkaido University, Japanese
• Results of 2003 Salmon Research Cruise of the Oshoro maru
  North Pacific Anadromous Fish Commission, 748, 1, 15, 2004
• Results of 2002 Salmon Research Cruise of the Oshoro Maru
  North Pacific Anadromous Fish Commission, 663, 1, 2003
• Wave Fluctuation with the Passage of a Depression
  YONETA Kunisaburo; MEGURO Toshimi; KAJIWARA Yoshiyuki; SAKAOKA Keiiciro, Bulletin of Fisheries Sciences, Hokkaido University, 53, 1, 51, 55, 2002
  Hokkaido University, English
• The 2000 International cooperative Salmon research Cruse of The Oshoro Maru
  North Pacific Anadromous Fish Commission, 547, 1, 2001
• Stock Abundance and Fish Size of Pacific Salmon in the North Pacific Ocean, 1998
  North Pacific Anadromous Fish Commission., 323, 1, 1998
• Oceanographic Conditions and Distribution of Pelagic Nekton in the Northwestern North Pacific Ocean during the Summer and Fall in 1995 and 1996
  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
  FACULTY OF FISHERIES, HOKKAIDO UNIVERSITY, Japanese

• The feedback system of gas exchange in the ocean
  Grants-in-Aid for Scientific Research
  2009 - 2012
  WATANABE Yutaka; NISHIOKA Jun; SAKAOKA Keiichiro; YOSHIKAWA Hisayuki; MINAMI Hideki; ONO Tsuneo
  ：In order to clarify how the nitrogen and carbon cycles in the ocean change spatiotemporally, we carried out the developments of the new estimations about these changes with a new sampling system. Applying the new estimations with the new sampling system to ocean observation, we had significant distributions of spatiotemporal distributions of nitrogen and carbon parameters in the North Pacific and the global ocean, indicating a possibility that we can obtain the detailed spatiotemporal distributions of change in ocean biogeochemical cycles.
  Japan Society for the Promotion of Science, Grant-in-Aid for Scientific Research (A), Hokkaido University, Competitive research funding, 22241001
• プランクトンネット採集特性に及ぼす船舶操作に関する研究
  Competitive research funding