Researcher Database

Researcher Profile and Settings

Master

Affiliation (Master)

  • Faculty of Fisheries Sciences Marine Bioresource and Environmental Science Marine Environment and Resource Sensing

Affiliation (Master)

  • Faculty of Fisheries Sciences Marine Bioresource and Environmental Science Marine Environment and Resource Sensing

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Profile and Settings

Profile and Settings

  • Name (Japanese)

    Fujimori
  • Name (Kana)

    Yasuzumi
  • Name

    200901042613900546

Achievement

Research Interests

  • Catch efficiency   Bycatch prevention   Fishing gear selectivity   マイクロネクトン   開閉式ネット   プランクトン   フレームトロール   オキアミ   LOPC   曳航式トランスデューサ   物質フローモデル   FMTネット   スルメイカ   可視化   多次元計測   ゼロエミッション   音響調査   

Research Areas

  • Life sciences / Aquaculture

Research Experience

  • 2010/05 - Today Hokkaido University Faculty of Fisheries Sciences
  • 2005 - 2010/04 Hokkaido University Faculty of Fisheries Sciences
  • 1995 - 2005 水産学部海洋生産システム学科生産システム設計学講座 助手
  • 1999/08 - 2000/06 Marine Laboratory, Aberdeen, UK Overseas Researcher, Ministry of Education
  • 1994 - 1995 北海道大学助手(水産学部漁業学科漁具漁法学講座) 助手
  • 1993 - 1994 日本学術振興会 日本学術振興会特別研究員

Education

  • 1990/03 - 1994/04  Tokyo University of Fisheries
  • 1988/04 - 1990/03  Tokyo University of Fisheries
  • 1987/04 - 1988/03  Tokyo University of Fisheries
  • 1983/04 - 1986/03  東京水産大学

Committee Memberships

  • 2022/04 -2024/03   The World Council of Fisheries Societies (WCFS)   Members of the International Program Committee for the 9th World Fisheries Congress

Awards

  • 2021/06 日本水産工学会 論文賞
     音響情報を用いたスケトウダラ稚魚に対するフレーム型中層トロール(FMT)の採集効率の推定 
    受賞者: 呂 振;向井 徹;藤森康澄;飯田浩二
  • 2000/04 日本水産学会 奨励賞
     
    受賞者: 藤森 康澄

Published Papers

  • Kenzo Tanaka, Makoto Tomiyasu, Ryo Kusaka, Shin Sugiyama, Evgeny A. Podolskiy, Yasuzumi Fujimori
    Fisheries Research 281 107203 - 107203 0165-7836 2025/01
  • Zhen Lu, TOHRU MUKAI, Yasuzumi Fujimori, Kohji Iida
    Journal of Marine Science and Engineering 2023/11/29 [Refereed]
  • Estimation of gillnets selectivity for greater lizardfish, Saurida tumbil (Bloch, 1795) in coastal waters of the Oman Sea
    M. Zellibooriabadi, S. Gorgin, Y. Fujimori, P. Zare, A. S. Niri, A. Susanto
    International Journal of Aquatic Biology 11 (2) 230 - 241 2023/07 [Refereed]
  • C. Jia, Y. Fujimori, X. Wang, C. Guan
    Fisheries Science 89 (5) 595 - 603 0919-9268 2023/06/15 [Refereed]
  • Makoto Tomiyasu, Yasuzumi Fujimori, Daichi Arima, Issei Fujita, Kenta Kozaki
    Fisheries Engineering 59 (3) 197 - 205 2023/02 [Refereed][Not invited]
  • 中国遼寧省渤海沿岸の発電所取水口周辺海域における大型海藻の分布とバイオマスへの影響要因
    賈 川, 藤森 康澄, 関 春江, 邵 魁双, 田 新華, 柳 圭澤
    水産工学 60 (1) 1 - 7 2023 [Refereed]
  • M. Tomiyasu, Y. Tanouchi, Y. Fujimori, M. Kaji, T. Hayashi, N. Matsubara, H. Yasuma, S. Shimizu, S. Katakura
    Journal of Marine Science and Technology-Taiwan 30 (2) 2022 [Refereed]
  • Yosuke Kuramoto, Yasuzumi Fujimori, Ryohei Ito, Yumi Kobayashi, Yasunori Sakurai
    Fisheries Research 242 106041 - 106041 0165-7836 2021/10 [Refereed]
  • Zhen Lu, Tohru Mukai, Yasuzumi Fujimori, Kohji Iida
    Journal of Marine Science and Technology (Taiwan) 29 (2) 185 - 196 1023-2796 2021 [Refereed]
     
    It is well known that there is bias using different sampling gear, such as a framed midwater trawl (FMT) and a ring net, when measuring the density and length distribution of target species. This limit is characterized by the sampling efficiency of the gear. Acoustic monitoring can be used to determine the sampling efficiencies of this gear, as its noninvasive, wide-range sweeps provide more reliable estimates of absolute abundance of the target species. The density measured by the gear can then be standardized by multiplying the initial density measurement by the derived sampling efficiency. In this study, we compared the estimated densities of the dominant zooplankton in the sound scattering layer (SSL) from acoustic monitoring to the densities of the same species measured using the FMT and ring net. The respective sampling efficiencies of this gear for zooplankton categories was then determined using linear regression models. For small Euphausiidae and Copepoda, the sampling efficiency of ring net was higher than that of FMT. In contrast, the ring net was less effective than FMT for large Euphausiidae. These results highlight that the entering and retention rates of the species depend on the type and characteristics of the survey gear, as well as the size and swimming ability of the target species.
  • 光崎健太, 藤森康澄, 山本潤, 富安信, 有馬大地, 澤村正幸, 清水晋
    水産工学 57 (3) 91 - 97 0916-7617 2021 [Refereed][Not invited]
  • 松井萌, 高山剛, 山本潤, 藤森康澄, 桜井泰憲
    日本水産学会誌 86 (2) 59 - 66 0021-5392 2020 [Refereed][Not invited]
  • Yasuzumi Fujimori, Yousuke Ochi, Shintaro Yamasaki, Ryohei Ito, Yumi Kobayashi, Jun Yamamoto, Osamu Tamaru, Yousuke Kuramoto, Yasunori Sakurai
    Fisheries Science 84 (6) 953 - 961 2018/11 [Refereed][Not invited]
  • FUJIMORI Yasuzumi
    日本LCA学会誌 14 (3) 213 - 218 2018 [Not refereed][Invited]
  • 片山 貴士, 藤森 康澄
    日本水産学会誌 2018 [Refereed][Not invited]
  • LU Zhen, 向井徹, 藤森康澄, 飯田浩二
    水産工学 55 (2) 135 - 144 0916-7617 2018 [Refereed][Not invited]
  • Sound production by Steindachner (Sebastes taczanowskii); relationship between sounds and fish density
    N. Matsubara, M. Sakamoto, S. Katakura, T. Akamatsu, R. Takahashi, Y. Fujimori, N. Kimura, K. Maekawa, H. Yasuma
    Contributions on the Theory of Fishing Gears and Related Marine Systems 10 209 - 216 2017 [Refereed][Not invited]
  • Effect of square mesh panel to selectivity exclude juvenile Thornhead (Sebastolobus macrochir) in pair trawls
    T. Endo, T.Katayama, Y. Fujimori, S. Shimizu
    Contributions on the Theory of Fishing Gears and Related Marine Systems 10 133 - 140 2017 [Refereed][Not invited]
  • Fish attracting effects of LED light of different colours
    M. Sakamoto, Y. Fujimori, N. Matsubara, H. Yasuma, S. Shimizu, S. Katakura
    Contributions on the Theory of Fishing Gears and Related Marine Systems 10 235 - 240 2017 [Refereed][Not invited]
  • 総論:持続的漁業に最適な漁獲技術とは?−資源回復を向上させるために−
    梶川和武, 藤森康澄, 山川 卓, 松下吉樹
    月刊海洋 49 (9) 1 - 6 2017 [Not refereed][Not invited]
  • Yuki Takahashi, Yasuzumi Fujimori, Fuxiang Hu, Nobuo Kimura
    NIPPON SUISAN GAKKAISHI 83 (6) 950 - 960 0021-5392 2017 [Refereed][Not invited]
     
    In this study, a method for optimizing the design of otter boards by computational fluid dynamics (CFD) analysis was developed. The optimization was based on response surface methodology. Here, a neural network model was employed for the response surface, then the design parameters of the otter board were optimized by a multi-objective genetic algorithm. In the optimization, lift and drag coefficients (C-L and C-D) were employed for the objective function such that C-L was maximized and C-D was minimized. The proposed method was applied to the biplane-type otter board. The hydrodynamic characteristics of the optimized otter board were compared with those of a comparative model. In the balanced model, one of the optimized models, C-L was slightly increased, and C-D was decreased by 14. compared with the comparative model. Furthermore, the separation area of the optimized model was decreased relative to the comparative model. From these results, it was concluded that the proposed optimization method is useful for designing otter boards with CFD.
  • Design optimization method of trawl otter board using CFD approach
    Y. Takahashi, Y.Fujimori, F. Hu, T. Tokai, N. Kimura
    Contributions on the Theory of Fishing Gears and Related Marine Systems 9 141 - 150 2015 [Refereed][Not invited]
  • 秋サケ定置網における海洋生物の偶発的捕獲
    小林由美, 増渕隆二, 蔵本洋介, 藤森康澄, 駿河秀雄, 成ケ沢重一, 白石智泰, 小林万里, 桜井泰憲, 石川昭
    えりも研究 12 15 - 19 2015 [Not refereed][Not invited]
  • 楠元彩香, 藤森康澄, 倉長亮二, 志村 健
    北海道大学水産科学研究彙報 北海道大学大学院水産科学研究科 65 (1) 39 - 45 1346-1842 2015 [Not refereed][Not invited]
     
    ハタハタActoscopus japonicusは,朝鮮半島東岸から沿海州,サハリン,カムチャッカを経て北米まで北太平洋北部に広く分布しており,水深450m以浅の大陸棚に生息する冷水性底魚類である(草刈,1994)。日本海には秋田県の牡鹿半島付近を産卵場とする「日本海北部系群」と韓国の東岸を産卵場にする「日本海西部系群」の2郡が存在している(京都府立海洋センター,2005)。藤原ら(2011)の報告によると,鳥取県のハタハタは日本海西部系群に属し,本系群は近年,我が国周辺における本州の漁獲量の半分以上を占めており,資源状態は高水準で横ばいと判断されている。また,本県においてハタハタはかけまわし漁法(倉長,2010)で漁獲されており,漁期は9月から翌年の5月までである。雌雄とも2歳から成熟過程に入り(三尾,1967),漁場に現れる満1歳の2~3月頃には体長100mm前後,2歳で体長150mm,3歳180mm,4歳200mm前後と見られ,メスの方がやや大きめのサイズになる(藤原ら,2011)。小型個体は市場価値が低く,さらに再生産の点で未成魚の保護が将来の資源保護に繋がることから,未成魚の漁獲を防ぐ必要がある。そのため同県水産試験場では,これまでにハタハタに対してコッドエンドの網目規制による管理を検討してきた(倉長ら,1999; 倉長,2010)。こういった小さな個体の混獲を減少させる方法としては,コッドエンドの網目拡大が有効であるが,その効果を定量的に評価するためには,網目選択性を求める必要がある。そこで,本研究では倉長(2010)と同様のデータを用いて,同かけまわし網における選択性のマスターカーブの推定を行い,本漁業における適切な目合について定量的に検討することを目的とした。
  • Yuki Takahashi, Yasuzumi Fujimori, Fuxiang Hu, Xiaoli Shen, Nobuo Kimura
    FISHERIES RESEARCH 161 400 - 407 0165-7836 2015/01 [Refereed][Not invited]
     
    Computational fluid dynamics (CFD) analysis was conducted for a biplane-type otter board model to validate the use of CFD analysis in designing otter boards. In the base mode (aspect ratio 3.0, camber ratio 15%, gap-chord ratio 0.91, and stagger angle 30 degrees), CFD analysis results show a maximum lift coefficient value of 1.65 for angle of attack 17.5 degrees, which is in agreement with results of the flume tank experiment (C-Lmax = 1.64 when alpha = 20 degrees) under the same conditions. In addition, the streamline and separation zones around the otter board were visualized and compared to the results from past tank experiment studies. CFD analysis results showed patterns similar to the experimental results, and the details of flow with a trailing vortex were confirmed. We concluded that CFD analysis is useful in the designing and development of otter boards. (C) 2014 Elsevier B.V. All rights reserved.
  • SAEKI KIMIYASU, KIMURA NOBUO, FUJIMORI YASUZUMI, YASUMA HIROKI, HISAMUNE SHUJI
    水産工学 日本水産工学会 51 (2) 133 - 137 0916-7617 2014/11/15 [Refereed][Not invited]
     
    There are many duties done by hand that are associated with the transportation of fish catch in fishing ports in Japan, and there are concerns with an excessive burden on the lumbar. This paper estimated the compression force in the lumbar intervertebral disk based on the weight carried and the work posture for six cases, and assessed the size of the burden by comparing the force with permissible values. The result of this assessment was that four of the cases exceeded the permissible values.
  • SAEKI KIMIYASU, KIMURA NOBUO, FUJIMORI YASUZUMI, YASUMA HIROKI, HISAMUNE SHUJI
    水産工学 日本水産工学会 51 (2) 93 - 103 0916-7617 2014/11 [Refereed][Not invited]
     
    In this paper, based on the analysis of the process and work during the handling of fish catch, a questionnaire on the fatigue and awareness of danger on each work was conducted at two fishing ports. the questionnaire was prepared using SD (Semantic differential) method. As a result, it was shown that carrying heavy box containing fish made workers feel fatigued. The work associated with transporting the catch of fish with the forklift and the work on slippery floor gave rise to dangers.
  • TAKAHASHI YUKI, FUJIMORI YASUZUMI, SAKAOKA KEIICHIRO, WATANABE YUTAKA, KIMURA NOBUO
    北海道大学水産科学研究い報 北海道大学大学院水産科学研究科編集出版委員会 64 (1) 1 - 8 1346-1842 2014/03 [Not refereed][Not invited]
     
    A seawater sampling system using underwater towed body was developed to obtain the water continuously. The systemwas composed of two towed bodies, which are vertically linked each other, to sample water in different layers. The range oftowing speed and target depth of the system were planned as up to 5.0 kt, and 10.0 to 20.0 m, respectively. At first, hydrodynamiccharacteristic of the towed body was examined using CFD analysis, and then the towing depth under the planned speedwas predicted dynamically. Finally, the validity of the towed body was confirmed at sea experiment. In the sea experiment,the depth of each towed body was measured changing towing speed on both conditions with hose to pump-up water and withoutit. The depth at the case with hose decreased by about 60 percent to compared with the case without hose. The depth of thelower side body with hose reached 20.0 m when the towing speed was 3.3 kt. Based on these results, it was estimated that thetowing speed to attain the depth of 20.0 m will increase to 5.0 kt by decreasing hose diameter from 18.0 mm to 8.0 mm, orincreasing each body weight to 150.0 kg.
  • N. Kimura, Y. Fujimori, H. Yasuma, K. Maekawa
    Fisheries Engineering 日本水産工学会 49 (3) 167 - 175 0916-7617 2013 [Refereed][Not invited]
     
    To clarify the process that leads to large-angle inclinations or even the capsizing of fishing boats, it is useful to be able to track dynamic changes in ship motions. These motions during fishing operations are not static, they change from moment to moment according to the fishing process, and it is important to understand the characteristics of the motions during each fishing operation process. To this end, in this study we focused on conducting a wavelet analysis to simultaneously estimate the time and frequency characteristics of the motions. We conducted a wavelet analysis of motion data obtained from a 160GT offshore trawler under standard running conditions and during Danish seine trawling. From the result obtained, we were able to accurately estimate motion characteristics as conditions changed during the fishing process. Periodical changes in motion were observed as a result of the resonance between the ship motions and the waves that were encountered.
  • Hydro-dynamic characteristics of the otter board by CFD approach
    Yuki Takahashi, Yasuzumi Fujimori, Fuxiang Hu, Xiaoli Shen, Nobuo Kimura
    Contributions on the Theory of Fishing Gears and Related Marine Systems 8 33 - 42 2013 [Refereed][Not invited]
  • WANG HUAN, ARAKAWA HISAYUKI, HAYASHI TOSHIFUMI, FUJIMORI YASUZUMI
    海洋調査技術 海洋調査技術学会 24 (2) 1 - 10 0915-2997 2012/09/30 [Refereed][Not invited]
  • Yukiko Yamashita, Yasuzumi Fujimori, Toru Mukai, Susumu Shimizu
    NIPPON SUISAN GAKKAISHI 78 (5) 903 - 912 0021-5392 2012/09 [Refereed][Not invited]
     
    The Laser Optical Plankton Counter (LOPC) has been used to evaluate abundance structure of micro-organisms like a zooplankton speedy. The sea experiments were conducted at twelve stations near Funka Bay, Hokkaido to examine the performance of the LOPC for in situ measurement of multispecies aggregation of zooplankton. The LOPC was mounted with ring net (80 cm mouth diameter) and towed vertically. Size and volume composition data of LOPC and net samples were compared each other. The particle size composition detected by the LOPC showed similar pattern with wet weight composition of copepods and amphipods in net samples. However, the ranges of equivalent spherical diameter of these species were overlapped. To measure in situ zooplankton community by species using LOPC, the measurement properties of each particle by specie should be identified and discriminated from LOPC data.
  • H.V. Dien, H. Yasuma, Y. Fujimori, N. Kimura
    The Journal of Japan Institute of Navigation 公益社団法人 日本航海学会 126 277 - 282 0388-7405 2012 [Refereed][Not invited]
     
    A study of coastal fishing boats (small purse seiners) was made in North Sulawesi province, Indonesia. The goal of this study is to clarify the rolling motion under fishing operation of the small purse seiners. First of all we examined the boat form of the purse seiners and practical conditions of rolling motion under fishing operations. Based on the data, the characteristics such boat's stability and rolling motion under fishing operation were calculated. The results of the analysis are as follows: the boat types were relatively slim around the hulls, and the boats had the round shape under water, and a boat still used by fishermen had extremely poor stability, and the roll angle increased remarkably in stage when the boat crossed the wave direction with hauling process, and results of Wavelet analysis showed that the purse seiners used in North Sulawesi had the same characteristics of rolling motion, and wavelet coefficients became large in hauling process.
  • Chang-Doo Park, Kyounghoon Lee, Seong-Hun Kim, Yasuzumi Fujimori
    FISHERIES SCIENCE 78 (1) 23 - 32 0919-9268 2012/01 [Refereed][Not invited]
     
    Recently, the increasing population of giant jellyfish Nemopilema nomurai has negatively affected coastal fisheries in Korea. As a result, the fishing industry has begun developing devices to prevent jellyfish capture. In this study, we assessed the performance of a conical jellyfish exclusion device in the coastal areas of Yokji Island in southern Korea during 2009. After hauling, we measured the length, diameter, and weight of the jellyfish and fish that were captured by the cod end and cover net. We found that the captured species included N. nomurai, silver croakers Pennahia argentata, yellow croakers Larimichthys polyactics, shotted halibut Eopsetta grigorjewi, largehead hairtails Trichiurus lepturus, and melon seeds Psenopsis anomala. The catch ratios of the giant jellyfish that entered the cod end in terms of weight ranged from 0.005 to 0.027. In contrast, the catch ratios of total fish in terms of weight and number were 0.793 and 0.835, respectively. On selectivity analysis of a conical separator for individual fish species, their exclusion ratios were independent of their length, and were similar to their observed exclusion ratios in terms of number. These results indicated that the conical jellyfish exclusion device performs well; however, some improvements are needed to minimize the escape of fish from the net.
  • Osamu Tamaru, Kazushi Miyashita, Nobuo Kimura, Yasuzumi Fujimori, Hideo Takahara, Teisuke Miura
    Bulletin of Fisheries Sciences, Hokkaido University 北海道大学大学院水産科学研究院 62 (3) 75 - 82 1346-1842 2012 [Not refereed][Not invited]
     
    In recent years in Japan, falling fish prices and rising fuel costs have worsened the economic conditions for many fisheries-dependent households. Many fishermen select the fishing ground in which they anticipate they can maximize their total catch, even when such grounds are far from their home harbor. As a result, fishermen have the potential to select a fishing ground in which they do not maximize their income. Especially the Japanese coastal squid jigging fishermen need to develop energy-saving squid jigging fishery practices, because of the high fuel consumption in comparison to other fisheries. By using the Management Simulation Method, we show that income fluctuations are caused by various factors. We used social factors and fishing ground factors in this simulation. According to the simulation results, small changes in social and fishing ground situations can result in changes in selection of the optimal fishing grounds. We conclude that the selection of fishing grounds by fishermen based only on their own knowledge and/or intuition might not result in choices that maximize their income, and it is necessary to develop objective methods to choose the fishing ground in which they can maximize their income.
  • FUJIMORI YASUZUMI
    Sen-ito Kogyo The Society of Fiber Science and Technology, Japan 67 (7) "P - 174"-"P-176" 0037-9875 2011/07/10
  • TAKEUCHI Sayaka, KIMURA Nobuo, FUJIMORI Yasuzumi
    The Journal of Japan Institute of Navigation 公益社団法人 日本航海学会 0 (124) 289 - 296 0388-7405 2011/03/25 [Refereed][Not invited]
     
    Danish seine trawl which is major offshore trawler in Hokkaido is regarded as having high risk of the resonance due to the characteristics of its operation method. However, as there are few study of ship motions in fishing operation, the actual condition is not clear. In this study, we perform estimating ship stability and the characteristics of ship motions by frequency analysis based on the data of ship motion. In the result, the ship stability decreased at short wave length and the resonance occurred between the natural period of rolling motion and the encountered period of wave in hauli...
  • H. Hei, H. Yasuma, K. Maekawa, Y. Fujimori, N. Kimura
    Mathematical and Physical Fisheries Science 数理水産科学研究会 9 85 - 94 1348-6802 2011 [Refereed][Not invited]
  • Motive performance of a new type of vertical axis rotor estimated by CFD analysis
    Y. Takahashi, Y. Fujimori, H.Yasuma, N. Kimura
    Mathematical and Physical Fisheries Science 9 75 - 84 2011 [Refereed][Not invited]
  • SAEKI Kimiyasu, HISAMUNE Shuji, FUJIMORI Yasuzumi, KIMURA Nobuo
    The Journal of Japan Institute of Navigation 公益社団法人 日本航海学会 125 233 - 240 0388-7405 2011 [Refereed][Not invited]
     
    Hundreds of work accidents during handling and carrying fish in fishing ports were extracted from accident database collected by JF Zengyoren (A nationwide federation of fisheries cooperatives in Japan). Accident data belong to main six accident types were classified by type of fishery, sex and age. Number of accidents in each category was compared with census of fishery activities and categories in which accidents occur with high frequency are statistically extracted. Based on the result, it was indicated that detailed case study should be conducted for trawl, boat seine and set net fishery.
  • Y. Takahashi, Y. Fujimori, K. W. Alex Masengi, K. Itaya, N. Kimura
    Mathematical and Physical Fisheries Science 数理水産科学会 8 29 - 41 1348-6802 2010 [Refereed][Not invited]
  • Development of a wind pump system with Savonius Rotor using computing aided engineering technique,
    J. Yamashita, Y. Fujimori, Y. Takahashi, H. Yasui, N. Kimura
    Mathematical and Physical Fisheries Science 8 42 - 53 2010 [Refereed][Not invited]
  • SAEKI Kimiyasu, MACHIBA Jun, HISAMUNE Shuji, FUJIMORI Yasuzumi, KIMURA Nobuo
    The Journal of Japan Institute of Navigation 公益社団法人 日本航海学会 124 201 - 209 0388-7405 2010 [Refereed][Not invited]
     
    In recent years, the way of handling and carrying fish within fishing ports has improved from a sanitary perspective. With a view of improving safety of workers, there has not been examined in any detail. This study reveals characteristics of accidents during handling and carrying fish. Upon hundreds of work accident data gathered by JF Zengyoren(A nationwide federation of fisheries cooperatives in Japan), accident types with high frequency or high fatality rate are extracted. Furthermore, using Fisher's exact test, factors influencing the occurrence of accidents are extracted.
  • DIEN Heffry Veibert, KIMURA Nobuo, FUJIMORI Yasuzumi, MANDAGI Ixchel Feibe
    The Journal of Japan Institute of Navigation 公益社団法人 日本航海学会 123 159 - 164 0388-7405 2010 [Refereed][Not invited]
     
    A series measurement of coastal fishing boats (small purse seiners) has been made in North Sulawesi province, Indonesia. The goal of this study is to clarify the physical characteristics of the small purse seiners in North Sulawesi. First of all we examined the boat form of the purse seiners and practical conditions under fishing operations. Based on the data, the characteristics such coefficient of fineness and the boat's stability were calculated. Typical fishing boats in Indonesia have conventional round hull shapes with a long bar keel. Purse seiners in North Sulawesi have different characteristics in every region, especially for principal dimensions and boat's designs. The results of the analysis are as follows: the boat types are relatively slim around the hulls and have the round shape under water, stability values are relatively small, and the cluster based on the principal dimensions and the coefficient of fineness has been categorized into two groups and three classes.
  • 藤森 康澄, 向井 徹, 山本 潤
    日本水産学会誌 76 (6) 1080 - 1082 0021-5392 2010 [Refereed][Not invited]
  • 鉄村 光太郎, 毛内 也之, 藤森 康澄
    Mathematical and physical fisheries science 数理水産科学会 7 (0) 43 - 57 1348-6802 2009/11 [Refereed][Not invited]
  • 竹内 冴佳, 木村 暢夫, 藤森 康澄
    Mathematical and physical fisheries science 数理水産科学会 7 (0) 28 - 42 1348-6802 2009/11 [Refereed][Not invited]
  • Y. Fujimori, R. Ishida, N. Honda
    Mathematical and physical fisheries science 数理水産科学会 7 90 - 96 1348-6802 2009 [Not refereed][Not invited]
  • YAMAUCHI Shigeki, MINE Hiroaki, KANEDA Tomonori, YOKOYAMA Yoshikatsu, FUJIMORI Yasuzumi, KIMURA Nobuo
    Journal of Fisheries Engineering 日本水産工学会 46 (1) 37 - 50 0916-7617 2009 [Refereed][Not invited]
     
    To clarify the difference of fish species attraction to artificial fish reefs according to the structure of fish reef units, fish catch experiments were performed at different reef units and a control area arranged in Furubira-cho offing, Hokkaido. The attraction effect of the fish reefs for each fish species due to differences in structure was ascertained by use of principal component analysis (PCA). As a result, accumulated contribution ratio of the directivity for the element of fish reef unit accounted for 89% and the main characteristics were explained by just four components. It was suggested that the characteristics of the attraction effect for each fish species were different among the types of the fish reefs.
  • Takashi Yonezawa, Yasuzumi Fujimori, Susumu Shimizu, Nobuo Kimura, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 75 (3) 402 - 411 0021-5392 2009 [Refereed][Not invited]
     
    This paper describes a process of modeling a towed sampling gear system that consists of a towed net and a vessel. Two inputs into this model are blade angle of a controllable pitch propeller (CPP) and warp length. To represent the flexibility of warp, a lumped mass model was derived by using the Lagrange equation of motion. The system model of the FMT (Framed Midwater Trawl) and R/V Ushio Mara of Hokkaido University accurately simulated the motion of the system in operation.
  • Takashi Yonezawa, Yasuzumi Fujimori, Susumu Shimizu, Nobuo Kimura, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 75 (3) 390 - 401 0021-5392 2009 [Refereed][Not invited]
     
    This paper describes the characteristics of a towed sampling gear system by using a linearized equation of motion. The linearized model was validated by comparing the results of the simulation and actual operation using the system of r/v Ushio Mara and a FMT (Framed Midwater Trawl). Damping factor and natural frequency, which are two parameters of a second-order system, were expressed as a function of the specifications of the sampling gear and operational conditions. As a result, the motion of the system was regarded as over-damping in common operations, and so the system generally seemed to be approximated by a first-order system. In this approximation, the value of the time constant remained constant even though the virtual mass of the net was varied. It was also found that the advantage of stable towing depth was obtained by using warp with a small scope ratio.
  • FUJIMORI YASUZUMI, YASUZUMI FUJIMORI, Graduate School of Fisheriese Science Hokkaido University
    NSUGAF The Japanese Society of Fisheries Science 74 (6) 1115 - 1115 0021-5392 2008/11/15
  • 本田 篤志, 藤森 康澄, 木村 暢夫
    Mathematical and physical fisheries science 数理水産科学会 6 (0) 146 - 151 1348-6802 2008/08 [Refereed][Not invited]
  • 吉田 洋二郎, 藤森 康澄, 木村 暢夫
    Mathematical and physical fisheries science 数理水産科学会 6 (0) 134 - 145 1348-6802 2008/08 [Refereed][Not invited]
  • 北野 貴章, 藤森 康澄, 木村 暢夫
    Mathematical and physical fisheries science 数理水産科学会 6 89 - 101 1348-6802 2008 [Refereed][Not invited]
  • Jun Yamamoto, Miyuki Hirose, Tetsuya Ohtani, Katashi Sugimoto, Kazue Hirase, Nobuo Shimamoto, Tsuyoshi Shimura, Natsumi Honda, Yasuzumi Fujimori, Tohru Mukai
    MARINE BIOLOGY 153 (3) 311 - 317 0025-3162 2008/01 [Refereed][Not invited]
     
    The fate of the giant jellyfish Nemopilema nomurai after death was examined in the southwest Sea of Japan. The density of dead jellyfish was greater than that of live animals. The dead animals are heavier than the Japan Sea Proper Water which occurs deeper than 200 m, suggesting that dead jellyfish sink to the sea floor. The sea floor survey, conducted with a towed video tape recorder (VTR) monitoring system between mid September and mid October, observed a total of 138 jellyfish during 28 of 29 operations. The density of carrion ranged between 0.2 and 5.1 individuals/1,000 m(2) (mean +/- SE = 1.1 +/- 0.2). Ophiuroids occurred abundantly at 23 jellyfish carcasses and a sea anemone was observed attached to five carcasses. The VTR surveys confirmed that carrion sinks to the sea floor not only during the winter, the normal end of life for medusae, but also during the fall. A trap survey baited with medusae was also employed, and four different species were sampled with the traps: the snow crab (Chionoecetes opilio), a shrimp (Pandalopsis japonica), the ivory shell (Buccinum striatissimum) and an ophiuroid (Ophiura sarsii). Much of the trap bait remained (49-68% weight-mean = 60.3%) during the 23 h soak-time, and the reduction in weight was greater than that observed by bacterial decomposition, suggesting benthic animals consume dead organisms. The present study indicates that dead N. nomurai sink to the sea floor continuously and were subsequently consumed by benthic scavengers.
  • FUJIMORI Yasuzumi, YAMASHITA Yukiko, ABE Masayuki, ITAYA Kazuhiko, MUKAI Tohru
    Fisheries engineering 日本水産工学会 44 (3) 197 - 204 0916-7617 2008 [Refereed][Not invited]
     
    A trousers-type framed midwater trawl (T-FMT) was developed for the simultaneous sampling of plankton and micronekton, which allows the use of two kinds of mesh sizes at the same time. This paper describes the performance of T-FMT in the survey of plankton and micronekton. In addition, the estimation of size selectivity for these small creatures was conducted by using the SELECT analysis expanded for a sub-sample from the trousers trawl experiment. The experiments for plankton and juvenile walleye pollock were conducted offshore of Usujiri, Hokkaido. Three kinds of codends were prepared: tw...
  • ITAYA KAZUHIKO, FUJIMORI YASUZUMI, SHIMIZU SUSUMU, KOMATSU TERUHISA, MIURA TEISUKE
    Fish. Sci. 73 (5) 1007 - 1016 0919-9268 2007/10/01 [Refereed][Not invited]
     
    To investigate fish density using rigid-mouth, towed net gear, such as a framed midwater trawl (FMT), it is necessary to know the catch efficiency. The catch efficiency with an FMT is described as the rate of fish entering the net (entering rate) versus the rate of fish retention, i.e. the mesh selectivity. This study investigated the change in the catch efficiency under several towing conditions using three types of FMT of different net mouth areas (4.0, 12.3, and 16.0 m(2)) with the same mesh size. The catch efficiency of the FMT was evaluated by comparing catch per unit effort obtained from each towing condition. The catch efficiency of FMT varied with towing speed and net mouth area. Particularly, the effect of net mouth area on the catch efficiency was greater than that of towing speed. Additionally, under the same towing condition, the catch efficiency for large length fish was lower than that for small length fish.
  • Yasuzumi Fujimori
    NIPPON SUISAN GAKKAISHI 73 (5) 925 - 926 0021-5392 2007/09 [Not refereed][Not invited]
  • Mohamed Gabr, Y. Fujimori, S. Shimizu, T. Miura
    FISHERIES RESEARCH 85 (1-2) 112 - 121 0165-7836 2007/06 [Refereed][Not invited]
     
    Understanding the fish escape behaviour through bycatch reduction devices is the cornerstone of their application as technical conservation measures. To evaluate square meshes and sorting grids as successful size-selective bycatch reduction devices in finfish trawls, we conducted a simulated trawling experiment to assess the effects of illumination, towing speed and mesh or grid orientation on the escape behaviour of undersized fish through square meshes and rigid grids. Juvenile masu salmon (Oncorhynchus masou) with average body length 13 cm were used as the experimental fish. A speed-controllable motor was used to tow the framed net in a circular water tank. An infrared CCD (charge-coupled devices) camera fixed to the towed net by means of a rotary connector was used to observe fish behaviour. In contrast to the active escape seen under lighted conditions, there was no active voluntary escape under dark conditions. As a result, no fish escaped through parallel and backward-sloping meshes, and only 13% of fish escaped through the forward-sloping meshes when the towing speed was increased. On the other hand, the encounter probability and passive escape through the longer openings in the backward-sloping grid increased under the dark condition, resulting in the highest escape ratio. This increased from 67 to 87% on increasing the towing speed from 1 to 1.5 knots, and shortened the swimming time before escaping from 5 to 1.5 min (the highest escape ratio and the shortest swimming time before escaping under the dark condition). Frame-by-frame analysis of some escape events demonstrated easy, passive fish escape through the grids with no change in the normal swimming direction. The results support the backward-sloping grid as an efficient bycatch-reduction device, especially in demersal trawling when placed well ahead of the codend, working in the dark at high towing speeds. (C) 2007 Elsevier B.V. All rights reserved.
  • GABR MOHAMED, FUJIMORI YASUZUMI, SHIMIZU SUSUMU, MIURA TEISUKE
    Fisheries Science 73 (3) 557 - 564 0919-9268 2007/06/01 [Refereed][Not invited]
     
    To assess the effect of towing speed and light intensity on the active escape of undersized fish through diamond and square mesh panels, a trawling experiment was simulated in a circular water tank. Juveniles of Japanese dace Tribolodon hakonensis (13-cm length class) were used as experimental fish. They were forced to swim inside a closed framed net with either diamond or square mesh (65-mm mesh size) that was moved using a speed-controllable motor. A submersible infrared CCD camera was used to observe and record the behavior of fish inside the net when it passed in front of the camera. Results indicated significant effects of towing speeds and light intensities (P < 0.05) on the escape of fish through the diamond and square meshes. Increase in light intensity enhanced the ability of fish to escape at lower towing speeds. At higher towing speeds, few fish could escape under light conditions. A strong negative correlation was found between towing speed and the frequency of fish escape (diamond mesh R-2 = 0.99, square mesh R-2 = 0.96). There was no significant difference between the numbers of fish escaping through the diamond and square meshes. These results suggest that the square-mesh panel may not be effective in the trawl cod end under dark or very low light intensity at high towing speed.
  • 津村良祐, 木村暢夫, 藤森康澄, 岩森利弘
    日本航海学会論文集 公益社団法人 日本航海学会 116 (116) 243 - 248 0388-7405 2007/03/25 [Refereed][Not invited]
     
    Fishing boats for the scallop cultivation in Hokkaido, Japan are small less than 10GT and harvest time of scallop is in winter season. As the fishing boats are moored to the big scale scallop cultivation facilities to do fishing work, the ship inclines about 6〜10 degrees into mooring side. Then, we aimed to develop the mooring device to reduce ship motion. If the large amplitude motion would generate under such inclining condition, the ship would be dangerous for capsize. In this study, we made the mooring device model for the fishing operation, that installed oil damper as absorber for ship motions. And we conducted model experiments under regular waves. As a result, the effect of the motion reduction was suggested by the use of the proposed mooring device.
  • 大杉康則, 木村暢夫, 藤森康澄, 阿部島直哉
    日本航海学会論文集 公益社団法人 日本航海学会 116 (116) 249 - 254 0388-7405 2007/03/25 [Refereed][Not invited]
     
    Maintenance of fishing ports have been advanced till today for the purpose of keeping for safe mooring of small fishing boats or improvement in cargo work efficiency. However, occurrence of mooring disasters of small fishing boats is still reported and it has been a serious problem. Then, in this study, we made experiments using a model ship based on the actual condition of the mooring method and considered interrelation between the ship motion and tension of mooring lines. In addition, we suggested safe mooring of small fishing boats such as how to take a mooring line and the mooring method.
  • 山下 由起子, 藤森 康澄, 向井 徹
    Mathematical and physical fisheries science 数理水産科学研究会 5 (0) 97 - 104 1348-6802 2007 [Refereed][Not invited]
  • Yoshioki Oozeki, Hu Fuxiang, Tadashi Tokai, Yasuzumi Fujimori
    Nippon Suisan Gakkaishi (Japanese Edition) 73 (5) 922  1349-998X 2007 [Refereed][Not invited]
  • 津村良祐, 木村暢夫, 藤森康澄, 岩森利弘
    北海道大学水産科学研究い報 北海道大学大学院水産科学研究科 57 (1/2) 19 - 24 1346-1842 2006/11/30 [Not refereed][Not invited]
  • Ken-Ichi Wakayama, Yasuzumi Fujimori, Kazuhiko Itaya, Osamu Murakami, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 72 (2) 174 - 181 0021-5392 2006/03 [Refereed][Not invited]
     
    Fishing experiments were carried out in Ishikari Bay, Hokkaido using a bottom gillnet with eight different mesh sizes to estimate the mesh selectivity for pointhead flounder Cleisthenes pinetorum. A total of 957 pointhead flounder were caught. The SELECT analysis with maximum likelihood method was used to fit the different functional models, the normal, lognormal, and bi-normal model. The catch data except for entangling catch was used for calculation. The bi-normal model was found to fit the data best. For the selectivity curve on the bi-normal model, the relative length (the ratio of fish length to mesh size) with the maximum efficiency was obtained as 1.87.
  • 木村 暢夫, 藤森 康澄, 岩森 利弘
    数理水産科学 数理水産科学研究会 4 (0) 103 - 112 1348-6802 2006 [Refereed][Not invited]
  • 山下 由起子, 藤森 康澄, 木村 暢夫
    数理水産科学 数理水産科学研究会 4 (0) 11 - 22 1348-6802 2006 [Refereed][Not invited]
  • WATANABE Kazuhito, TAHARA Kiyotaka, FUJIMORI Yasuzumi, SHIMIZU Susumu, MIURA Teisuke
    Environmental science 環境科学会 19 (1) 15 - 24 0915-0048 2006 [Refereed][Not invited]
  • S Torisawa, K Miyashita, R Kawabe, Y Fujimori, T Oshima, S Honda, K Sato
    FISHERIES RESEARCH 77 (1) 4 - 9 0165-7836 2006/01 [Refereed][Not invited]
     
    Although visual information can help to monitor fish behavior in situ, quantitative analysis from images is difficult. There is little quantitative information from images on fish behavior in situ. In this study, we used digital still-picture loggers (DSLs) to monitor the bearing and tilt angles of walleye pollock, Theragra chalcogramma, in a trawl in situ. We attached two DSLs to a trawl net and recorded still pictures of fish near the mouth of the trawl. Eleven pictures of walleye pollock were obtained during 79 trawl surveys. From the still images, we calculated the bearing and tilt angles of the fish using the ratio of body length and body height. We confirmed the accuracy of the calculated angles by comparing the computed angles using image-processing software. The calculated angles agreed with the angles computed using the software. Therefore, our simple method can be used to monitor fish bearing and tilt angles in situ. Based on our results, bearing angles of walleye pollock were not shown in the same direction to a trawl. Furthermore, the fish tilt angles differed significantly between adults and juveniles. (C) 2005 Elsevier B.V. All rights reserved.
  • Y Fujimori, K Chiba, T Oshima, K Miyashita, S Honda
    FISHERIES SCIENCE 71 (4) 738 - 747 0919-9268 2005/08 [Refereed][Not invited]
     
    Variations in trawl dimension, bottom contact, and catch with differing warp lengths during walleye pollock surveys conducted by the Fisheries Research Agency were examined. The ratio of warp length to fishing depth (scope ratio) was set at 2.5, 3.0 and 3.5 at depths of 110 m. At a 2.5 scope ratio, the net mouth shape and footgear contact fluctuated, as the trawl door did not contact the bottom. Footgear contact was complete when the scope ratio was 3.0 or more. Walleye pollock, sculpins and flatfishes were the main catch in all tows, and the catch increased with scope ratio. There was no difference in the length frequency of walleye pollock (n = 300) captured at 2.5 and 3.0 scope ratio. However, the length frequency at 3.5 was significantly different from that of other scope ratios. These results suggest that at a scope ratio of 3.0 or more, the trawl door will not leave the bottom at any depths. To compliment echo surveys for walleye pollock, a 3.0 scope ratio would be optimal, since the catch data for a 3.5 scope ratio was dissimilar from that of scope ratios.
  • CD Park, EC Jeong, JK Shin, HC An, Y Fujimori
    FISHERIES SCIENCE 70 (4) 553 - 560 0919-9268 2004/08 [Refereed][Not invited]
     
    Fishing experiments were carried out in Yeongil Bay, Korea using an encircling gill net with four different mesh sizes and two different hanging ratios to measure the mesh selectivity for gizzard shad Konosirus punctatus. Twenty-six trials were conducted giving a total catch of 485 gizzard shad. The 'share each length's catch total' (SELECT) analysis with maximum likelihood method was used to fit the different functional models, the normal, lognormal, and bi-normal model, for a selectivity curve to the catch data. In addition, two cases in which the relative fishing intensity was either estimated or fixed were compared. The bi-normal model with the fixed relative fishing intensity was found to fit the data best. For the selectivity curve on the bi-normal model, the relative length (the ratio of fish length to mesh size) with the maximum efficiency was obtained as 3.70. From this, the focal fish lengths in the commercial encircling gill net, with mesh size ranging from 5.0 to 6.0 cm, were inferred to be 185-22.2 cm.
  • 阿部 真之, 藤森 康澄, 清水 晋
    数理水産科学 数理水産科学研究会 2 (0) 124 - 127 1348-6802 2004 [Not refereed][Not invited]
  • T Iwata, S Shimizu, Y Fujimori, T Miura
    FISHERIES SCIENCE 69 (3) 657 - 659 0919-9268 2003/06 [Refereed][Not invited]
  • 藤森 康澄
    数理水産科学 数理水産科学研究会 1 (0) 21 - 26 1348-6802 2003 [Refereed][Not invited]
  • Kosuke Yokota, Yasuzumi Fujimori, Fuxiang Hu, Tadashi Tokai
    FISHERIES SCIENCE 68 469 - 470 0919-9268 2002 [Refereed][Not invited]
  • K Yokota, Y Fujimori, D Shiode, T Tokai
    FISHERIES SCIENCE 67 (5) 851 - 856 0919-9268 2001/10 [Refereed][Not invited]
     
    To analyze the effect of thin twine on gill net size selectivity, a series of fishing experiments using gill nets of two twine thicknesses (no. 0.8 of 0.16 mm diameter and no. 3 of 0.28 mm diameter) and three nominal mesh sizes (41 mm, 46 mm and 51 mm) was conducted in outdoor water tanks containing a rainbow trout (Oncorhynchus mykiss) population of known size frequency. For nets of the same nominal mesh size, mesh openings of the no. 0.8 twine nets were approximately 2 mm larger than those of the no. 3 twine nets. The effects of both mesh opening and twine thickness are combined in the conventional analysis with the selectivity curve against fish length. Selectivity against the ratio of fish girth to mesh perimeter was calculated to avoid the direct effect of changes in mesh openings due to twine diameter at the same nominal mesh size. Results demonstrated that the thinner twine gill net was more likely to capture rainbow trout of smaller girth than the mesh perimeter. Fish with girths smaller than the mesh perimeter were often retained by the net with its body tangled by the thinner twine, possibly due to the increased flexibility of the thinner twine.
  • FUJIMORI Yasuzumi, TOKAI Tadashi
    Fisheries Science Blackwell Publishing 67 (4) 644 - 654 0919-9268 2001/08 [Refereed][Not invited]
     
    A maximum likelihood method of estimating gillnet selectivity when data are obtained by gillnet fleets consisting of several nets of differing mesh size is presented in this paper. The SELECT model is expanded by application of the relative length (i.e. the ratio of fish length to mesh size) to obtain a master curve of gillnet selectivity. Four kinds of functional model, normal, lognormal, skew-normal and bi-normal are fitted to the data. In addition, two cases in which the relative fishing intensity is either estimated or fixed by catch effort are compared. The bi-normal model has the lower model deviance regardless of whether the relative fishing intensity is estimated or not. The estimation of relative fishing intensity by catch effort is also examined in which the estimates of the parameter of the SELECT model are compared with the catch effort as determined by the number of nets of each mesh size used. For the bi-normal model these quantities compare well. Thus, it is concluded that this method gives reliable estimates even if data for each mesh size is obtained with different catch efforts.
  • K Itaya, Y Fujimori, D Shiode, Aoki, I, T Yonezawa, S Shimizu, T Miura
    FISHERIES SCIENCE 67 (3) 436 - 443 0919-9268 2001/06 [Refereed][Not invited]
     
    A sampling trawl with a rigid mouth; that is, the frame trawl, was designed so as to catch the large larval and juvenile fish more efficiently. The net consisted of four 13 m panels (nylon multifilament and twine diameter phi 0.75 mm, mesh size 8 mm). The frame of the net's mouth was composed of four stainless steel pipes (length 4m, diameter phi 76 mm, thickness 5 mm). Several operations were conducted to investigate the capability of catching juveniles. A lot of Sardinops melanostictus juveniles, which are generally difficult to catch, were caught during every operation. Underwater observations proved that juveniles could not elude the capture. The frame trawl requires no special handling and is possible to operate in a rough sea.
  • Daisuke Shiode, Yasuzumi Fujimori, Fuxiang Hu, Susumu Shimizu, Teisuke Miura
    Fisheries Science Japanese Society of Fisheries Science 67 (1) 110 - 117 0919-9268 2001/02
  • Body girth of fish caught by gillnets of different twine thickness
    K. Yokota, T. Tokai, F. Xu, Y. Fujimori
    UPV Journal of Natural Sciences (Special Issue: Proceedings of the International Seminar on Responsible Capture Fisheries in Coastal Water of Asia) 6 77 - 85 2001 [Refereed][Not invited]
  • Sampling performance of a depth-controllable gillnet (towed gillnet)
    Proceedings of the International Symposium on Advanced techniques of Sampling Gear and Acoustical Surveys for Estimation of Fish Abundance and Behavior, Hakodate, Japan 120 - 127 2001 [Not refereed][Not invited]
  • MIURA Teisuke, WATANABE Kazuhito, SHIODE Daisuke, FUJIMORI Yasuzumi, SHIMIZU Susumu
    Environmental science 環境科学会 13 (5) 612 - 617 0915-0048 2000/12/31 [Refereed][Not invited]
     
    The squid raw material supply system models in Japan and in the case of a local city Hakodate were investigated from the concept of nitrogen balance. The amount of nitrogen in imported squid material was 2, 755 tons and that in exported all products made from squid material was 2, 311 tons. As the result, 409 tons nitrogen remained in the area of Hakodate. Only the nitrogen of 62 tons (2.2% of the input) was abandoned as a waste in the area of Hakodate except the nitrogen of amount of 347 tons that man eats. This value shows that Hakodate is a region that circulates well from the respect of squid's nitrogen balance. There is a problem in the processing of the feed maker of squid's internal organs by charge. It means that squid's internal organs are not evaluated. In Japan, the industry that relates to the squid imports a large amount of raw materials as well as other food industries, and consumes the most domestically. The entire squid import has only 21, 000 tons to compare with that of export for 730, 000 tons in 1997. It means nitrogen 18, 200 tons input and 1, 090 tons output. The nitrogen of 17, 100 tons stays domestically as a result. It is necessary to promote the development of the commodity which can be consumed in the foreign countries or which can be exported to improve this state.
  • FUJIMORI Yasuzumi, Yasuzumi Fujimori, Graduate School of Fisheries Hokkaido University
    NSUGAF The Japanese Society of Fisheries Science 66 (4) 607 - 610 0021-5392 2000/07/15
  • Y Fujimori, K Abe, S Shimizu, T Miura
    FISHERIES SCIENCE 66 (3) 424 - 431 0919-9268 2000/06 [Refereed][Not invited]
     
    The escape behavior of juvenile salmon from nets was investigated in a water tank experiment by using a netting panel with several types of specifications in view of by-catch prevention in a set-net fishery. Twelve diamond mesh nets and four square mesh nets with different mesh size (mesh openings when stretched: 14.0, 15.6, 17.2, and 20.5 mm; hanging ratio of diamond mesh: about 0.5, 0.70, and about 0.8) were used for the netting panel. A comparison of the passing ratio in each hanging ratio of diamond mesh showed the passing ratio of the panel with hanging ratio of 0.70 was the highest in each mesh size. In addition, the diamond mesh with hanging ratio of 0.70 had the higher passing ratio than that of square mesh in each mesh size. From these results, it was determined that the diamond mesh with hanging ratio of 0.70 was appropriate for the prevention of juvenile salmon by-catch. However, the shape of the diamond mesh collapses easily with the tension caused by bag-net hauling, so it is necessary to attach a device and employ a haul technique that allows the by-catch to escape.
  • SHIMIZU Susumu, FUJIMORI Yasuzumi, MIURA Teisuke, NASHIMOTO Katsuaki
    Bulletin of the Faculty of Fisheries, Hokkaido University 北海道大学 51 (1) 13 - 23 0018-3458 2000/03 [Not refereed][Not invited]
  • FUJIMORI Yasuzumi, TOKAI Tadashi
    Bulletin of the Japanese Society of Fisheries Oceanography 水産海洋学会 63 (1) 14 - 25 0388-9149 1999/02/01 [Not refereed][Not invited]
  • Yasuzumi Fujimori, Daisuke Shiode, Norihiko Baba, Susumu Shimizu, Teisuke Miura
    NIPPON SUISAN GAKKAISHI The Japanese Society of Fisheries Science 65 (1) 26 - 32 0021-5392 1999 [Refereed]
     
    The following two behavioral experiments were conducted in a small water tank (90×45×30cm) to examine the characteristics of activity of juvenile walleye pollock. 1) Locomotor activity was observed with an infrared ray sensor under the different light-dark conditions, 12h light (100lx) and 12h dark (<0.1lx) cycles (LD), 24h constant dark (DD) and 24h constant light (LL). 2) Fish behavior to net under different illuminance (0.1, 1.0, 100lx) was recorded by a CCD camera. The activity of juvenile walleye pollock showed clearly a diurnal rhythm under the LD condition, which gradually decreased after 18 : 00 and increased after 6 : 00. However, the particular rhythms such as circadian rhythm were not shown in other conditions. The activity of juvenile walleye pollock was considered to largely depend on illuminance condition. In the experiment with relation to behaviors toward a net, the linear regression coefficient between the cumulative number of passing through the net and elapsed time was nearly constant with various illuminance, while the regression coefficient of the approach to it increased with illuminance. The passing rate, the coefficient of passing/the coefficient of approach decreased gently as illuminance increases. The probability of capture for juvenile walleye pollock by a mid-water trawl was estimated separately at day and night based on the method of Barkley.
  • Daisuke Shiode, Yasuzumi Fujimori, Ichiro Aoki, Susumu Shimizu, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 64 (3) 412 - 417 0021-5392 1998 [Refereed][Not invited]
     
    Sampling for Japanese sardine Sardinops melanostictus was performed offshore of Izu-Oshima, Japan in April 1995 to investigate the sampling performance of a towed midwater gillnet on a research vessel. The towed midwater gillnet (Towed type) and the midwater driftnet (Drift type) of 33, 43 mm mesh size were used. The nets were made of monofilament nylon with twine diameter 0.284 mm. The Drift type was set at the depth of 30 m, hanging on six buoys with ropes. The depth of the Towed type was set in accordance with the depth of sardine shoals located with an echo sounder (50 kHz). The Towed type caught about one hundred sardines per operation. The length frequencies of sardines caught by both net types were similar. The sampling performance of the Towed type was similar to the Drift type. Additionally, the Towed type was easier to cast than the Drift type, because the net construction of the Towed type was simpler. It is considered that the Towed type is efficient gear for sampling pelagic fishes on research vessels.
  • Daisuke Shiode, Yasuzumi Fujimori, Susumu Shimizu, Nobuyuki Imai, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 63 (6) 920 - 927 0021-5392 1997 [Refereed][Not invited]
     
    A new type of depth-controlled gillnet was designed for fish sampling surveys. The net was joined to a vessel with a single warp to control net depth. Flume-tank experiments were performed using two model nets (1/30 scale) to determine the optimum net design. In one model (Direct-type), the warp and net were joined directly, while in the other model (Bridle-type), the joint between the warp and net passed through the bridle. Next, an experiment was conducted using the full-scale net at sea to investigate the effect of operational factors, warp and vessel speed (propeller pitch) on net depth. The shape of Direct-type was better than that of Bridle-type shape. The former sank faster than the latter at the speed of 25 cm/s (0.5 kt) speed, and was thus selected as the design for the fullscale net. Net depth could be controlled smoothly by paying out of the warp or change of propeller pitch at sea. This change of depth with time fit the first order lag model.
  • Tadashi Tokai, Shigeyuki Omoto, Yasuzumi Fujimori, Haruyuki Kanehiro, Ko Matuda
    Nippon Suisan Gakkaishi (Japanese Edition) 63 (5) 715 - 721 0021-5392 1997 [Refereed][Not invited]
     
    A separator-trawl used for a mantis shrimp catch in Tokyo Bay has a separator panel and two codends separator net-panel (100 mm stretched mesh length) on part of the top of the first codend (62 mm mesh length) which is covered with the second codend (33.6 mm mesh length). The fishermen hoped mantis shrimp as a main target species would be caught in the second codend and be separated from starfishes retained in the first codend, because large amounts of starfishes cause difficulty in fishermen's hand-sorting on deck. Separation efficiencies of the trawl were obtained from the catch numbers in the two codends in a fishing experiment. Separation efficiency between species i and j is defined as γi+γj-1, where γi is the recovery ratio in the codend for i-species, that is, a proportion of the i-species catch number in the i-species codend. While the recovery ratio for starfish in the first codend was 0.96, that for mantis shrimp in the second codend was 0.66 which was not so high as expected. Thus, separation efficiency between mantis shrimp and starfish was 0.62. Although the separator net-panel has enough large mesh size for small animals, e.g. small crab Carcinoplax vestina, some species of low swimming ability failed to pass through the separator panel and were retained in the first codend. This implies that separation performance of the separator-trawl depends on the swimming ability of each species in the net as well as mesh selectivity of the separator net panel.
  • Y Fujimori, T Tokai, S Hiyama, K Matuda
    FISHERIES RESEARCH 26 (1-2) 113 - 124 0165-7836 1996/04 [Refereed][Not invited]
     
    To study the effect of gear selectivity on kuruma prawn (Penaeus japonicus) fishing experiments using trammel nets with different mesh sizes were conducted in Ohmi Bay, Yamaguchi Prefecture, Japan. To provide comparative data the same nets were used on kuruma prawn of known size composition under controlled conditions in a water tank at the Yamaguchi Prefectural Naikai Fisheries Experimental Station, The experiments clarified the gear efficiency of trammel nets for kuruma prawn and confirmed the optimal mesh size for resource conservation. Mesh selectivity by a trammel net used for kuruma prawn shows a peaked curved, with the efficiency at the peak of mesh selectivity increasing in proportion to the mesh size. From the resulting catching efficiency data, an optimum mesh size of 42.8 mm was determined for kuruma prawn of 110-140 mm body length. This paper includes a method for estimating the efficiency of gillnets, which is an extension of Kitahara's method.
  • Yasuzumi Fujimori, Susumu Shimizu, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 62 (3) 428 - 433 0021-5392 1996 [Refereed][Not invited]
     
    The performance of bio-polyester (Biopole) as a net material for traps was investigated in a water tank experiment using the freshwater shrimp Palaemon paucidens. The numbers of shrimp that settled on net panels composed of different materials and placed side by side in pairs were measured. Net panel materials examined included bio-polyester, nylon-monofilament, nylon-multifilament and steel. A smooth surface bio-polyester without cracks was compared with a rough surface biopolyester with many cracks caused by solution. More shrimp settled on the bio-polyester panels with a smooth surface than the nylon-multifilament and steel net panels, but less than on the nylon-monofilament panels. When bio-polyester panels with many cracks were examined, fewer shrimp settled on the bio-polyester panels than on the two nylon panel types, but more than on the steel net panels. These results suggested that the texture changed the attractiveness of the bio-polyester to the shrimps.
  • Takashi Yonezawa, Yasuzumi Fujimori, Susumu Shimizu, Katsuaki Nashimoto, Teisuke Miura
    Nippon Suisan Gakkaishi (Japanese Edition) 62 (2) 254 - 261 0021-5392 1996 [Refereed][Not invited]
     
    The purpose of this work is to develop a midwater trawl net to survey fish stock. A constant net mouth opening is necessary in order to measure fish stock densities accurately. For this purpose, canvas kites were attached to the midwater trawl net, instead of floats and weights. The area of canvas kites attached to the headrope and groundrope was derived from the equilibrium between the sum of vertical components of the towing force and the drag of the net. The model test were made with a scale of one-twentieth in a flume tank, in which the static characteristics of the kite-type net were compared with those of the float-type net. Further, a full-scale kite-type net was examined aboard the RV "Ushio-maru". The kite-type model maintained a more constant form and net-mouth area than the float type net over a range of current speeds. The full-scale kite-type net maintained a constant net mouth height of 7 meters, according to the plan. From these results, we conclude that the kite-type net is to be recommended for a better sampling device for fish stock assessments.
  • Y Fujimori, T Tokai, ZL Liang, K Matuda
    NIPPON SUISAN GAKKAISHI 61 (6) 868 - 873 0021-5392 1995/11 [Refereed][Not invited]
     
    This paper describes the capturing process of gillnets as a numerical network model. This model mainly consists of three processes: fish activity process such as periodic activity to light intensity, etc.; encountering process of fish to net; and net-entangling process e.g. mech selectivity. The parameters of the equations in the model were estimated from the data obtained through experiments conducted in an outdoor tank from dawn to night for rainbow trout Oncorhyncus mykiss. Changes of catch number were computed by the Monte-Carlo simulation of this model. The catch number in the simulation after sunset, which corresponded with that in the fishing experiment in the outdoor tank. It is therefore supposed that the model is applicable to the gillnet capturing process.
  • Yasuzumi Fujimori, Tadashi Tokai, Ko Matuda
    Nippon Suisan Gakkaishi (Japanese Edition) 60 (5) 577 - 583 1349-998X 1994 [Refereed][Not invited]
     
    This paper describes the modeling of a fish-capturing process on a gillnet by evaluating the diurnal activity of fish and behavior to the net. Diurnal activity was investigated in an outdoor experiment and fish behavior to the net was studied at different light intensities in an indoor experiment with rainbow trout Oncorhyncus mykiss. The activity of rainbow trout is diurnally periodic, increasing rapidly before sunrise at dawn, and decreasing gradually after sunset at dusk in the outdoor experiment. The activity of rainbow trout is thought to depend not only on lignt intensity but also on the endogenous rhythm of the fish. The activity increased over 101 lx light intensity in the day-time indoor experiment. Fish seldom encounter the net under 102 lx, and the frequency of encounter to the net began to increase at 101 lx and saturated at 10-2 lx. The net encounter rate was thus estimated as a function of time. The encounter rate showed two remarkable peaks at dawn and dusk, which account for the mazume phenomenon of an increase in the catch of gillnets in the twilight. © 1994, The Japanese Society of Fisheries Science. All rights reserved.
  • LIANG Zhenlin, MATSUDA Ko, TOKAI Tadashi, FUJIMORI Yasuzumi, KANEHIRO Haruyuki
    水産工学 日本水産工学会 30 (1) 1 - 8 0916-7617 1993/08 [Refereed][Not invited]
     
    This paper describes the reactions of freshwater fishes to He-Ne laser light and discuss herding effect of moving laser screen. The indoor tank experiments were conducted to examine herding effect at different fish numbers (10, 20 and 30 fish) and different species (Japanese dace Tribolodon hafronensis, carp Cyprinus carpio and rainbow trout Oncorhynchus mykiss). In outdoor tank, it was attempted to herd rainbow trout at different moving speeds of laser screen. Laser temporally dispersed fish school, and then fish again swam in school avoiding the laser. Thereby laser can drive fish into an area of tank. Fish are however considered to leam to escape through laser screen, since herding effects decreased, following repeated exposure to the stimuli of laser screen. Laser could herd fish more effectively in the dark than in the light at the indoor tank experiment. The larger fish number of Japanese dace was, the sooner laser screen could herd. Moreover, the herding effect was different among species. The proportion of herded rainbow trout decreased over 25 cm/s of laser screen moving speed. It is therefore resulted.that the herding effect depends on several factors e. g. fish school behavior and swimming performance.
  • LP LOSANES, K MATUDA, Y FUJIMORI
    FISHERIES RESEARCH 15 (3) 217 - 227 0165-7836 1992/12 [Refereed][Not invited]
     
    An outdoor tank experiment was conducted to study the influence of soaking time on the catch efficiency of gillnets and entangling nets (trammel and semi-trammel nets). The catch efficiency of the nets was also compared with detecting the difference between entangling nets and gillnets in relation to soaking time. Nets of the same mesh sizes were set simultaneously in separate outdoor tanks containing 200 rainbow trout (Oncorhynchus mykiss) whose composition size was known. The experiment was carried out at night using four soaking times; 0.5, 1, 3 and 5 h. The variations of the catch efficiency of all nets had a U-shaped trend, showing that the efficiency increased at the shortest time (0.5 h), decreased at the intermediate time (1 h), and increased again at the longest soaking time. The average catch efficiency of the semi-trammel net appeared to be slightly higher than that of the gillnet.
  • LP LOSANES, K MATUDA, Y FUJIMORI
    FISHERIES RESEARCH 15 (3) 229 - 242 0165-7836 1992/12 [Refereed][Not invited]
     
    The selectivity of gillnets and entangling nets (trammel and semi-trammel nets) was estimated directly by setting nets in outdoor tanks containing a known population of rainbow trout (Oncorhynchus mykiss). From the directly estimated selectivity, the entangling effect of the trammel and semi-trammel nets was estimated using the gillnet as the standard of comparison. The study assumed that the selectivity curve of gillnets was a slightly skewed unimodal curve while that for entangling nets was bimodal. The bimodal curve was dissected into two unimodal components by presuming that the first component has a selective nature similar to a gillnet while the second component was attributed to additional entangling - a method of capture peculiar to entangling nets. The selectivity of gillnet and the components of the selectivity of entangling nets were fitted using a logarithmic normal distribution. The components of the selectivity curve of the semi-trammel net had higher amplitudes but narrower ranges than the trammel net. The trammel net appeared to entangle a wider range of size and inclined towards smaller individuals. The selectivity of the semi-trammel net attributed to entangling was more severe than the trammel net but had a higher amplitude. The selection range of the selectivity curves of the entangling nets was wider than that of the gillnets. It was suggested that the selectivity of the entangling net could be estimated by comparing it with that of a gillnet of the same mesh size.
  • Yasuzumi Fujimori, Ko Matuda, Loel P. Losanes
    Nippon Suisan Gakkaishi (Japanese Edition) 58 (2) 193 - 198 1349-998X 1992 [Refereed][Not invited]
     
    The selectivity curve of the gillnet and the semi-trammel net was estimated by applying a skew-normal function. The parameters of the model were obtained using the Monte Carlo simulation method. The data were taken from a large outdoor water tank containing a large number of rainbow trout Oncorhyncus mykiss of known size composition. A large tank was used for the purpose of minimizing any statistical error which may be caused by smaller tanks. The length distribution of the catch from the calculated value was in close agreement with the experimental value. Thus, the skew-normal function could well describe the selectivity curve of the gillnets. The selectivity curve of the semi-trammel net had a larger degree of skewness than that of the gillnet. However, the skewness of the semi-trammel net decreased linearly with an increase in mesh size. Thus, the entagling effect of the semi-trammel net was higher for larger fish. © 1992, The Japanese Society of Fisheries Science. All rights reserved.
  • Yasuzumi Fujimori, Ko Matuda, Loel P. Losanes, Atsushi Koike
    NIPPON SUISAN GAKKAISHI 56 (12) 2019 - 2027 1349-998X 1990 [Refereed][Not invited]
     
    The difference on the fishing performance of a bottom gillnet and semi-trammel net was elucidated by evaluating the catching efficiency and absolute selectivity of the nets. The data were obtained from an outdoor water tank experiment using a group of rainbow trout Oncorhyncus mykiss of known size composition. The influence of light intensity on the catch taking the mesh size and construction of the net into consideration was also evaluated. The results showed that gillnet was more effective than semi-trammel net when the mesh size of the net was appropriate with the size of fish. Likewise, light has greater influence to the catch of semi-trammel net than a gillnet. © 1990, The Japanese Society of Fisheries Science. All rights reserved.

MISC

Presentations

  • 坂本誠, 藤森康澄, 松原直人, 安間洋樹, 清水晋, 片倉靖次
    日本水産学会大会講演要旨集  2018/03
  • 松原直人, 坂本誠, 片倉靖次, 赤松友成, 高橋竜三, 藤森康澄, 木村暢夫, 前川和義, 安間洋樹
    日本水産学会大会講演要旨集  2018/03
  • 坂本誠, 松原直人, 安間洋樹, 清水晋, 藤森康澄, 片倉靖次
    日本水産学会大会講演要旨集  2017/03
  • 三陸沖合底びき網に導入された角目網パネルのキチジに対するサイズ選択性の推定  [Not invited]
    遠藤拓也, 片山貴士, 藤森康澄
    日本水産学会  2017/03
  • LED灯光の特性の違いによる集魚効果の比較  [Not invited]
    坂本誠, 松原直人, 安間洋樹, 清水晋, 藤森康澄, 片倉靖次
    日本水産学会  2017/03
  • 水中カメラを用いたサケ定置網に侵入するゼニガタアザラシの個体識別  [Not invited]
    伊藤遼平, 藤森康澄, 桜井泰憲, 小林由美, 山本潤, 蔵本洋介
    日本水産学会  2017/03
  • FUJIMORI Yasuzumi, YASUMA Hiroki, YAMAGUCHI Atsushi, ADACHI Shinji
    Proceedings of the International Symposium on Okhotsk Sea & Sea Ice  2017/02
  • 松原直人, 坂本誠, 片倉靖次, 赤松友成, 高橋竜三, 藤森康澄, 木村暢夫, 前川和義, 安間洋樹
    日本水産学会北海道支部大会講演要旨集  2016/10
  • エゾメバルの鳴音の音響特性,および鳴音受信頻度と個体密度の関係  [Not invited]
    松原直人, 坂本誠, 片倉靖次, 赤松友成, 高橋竜三, 藤森康澄, 木村暢夫, 前川和義, 安間洋樹
    日本水産学会支部大会  2016/10
  • 中西部太平洋のマグロ類漁業における東アジア各国の生産・貿易量の相互関係と影響力の検証  [Not invited]
    劉 昱謙, 藤森康澄
    日本水産学会大会  2016/03
  • 北海道襟裳地域のサケ定置網内におけるゼニガタアザラシとサケの行動観測  [Not invited]
    伊藤遼平, 藤森康澄, 小林由美, 桜井泰憲, 三谷曜子, 蔵本洋介
    日本水産学会大会  2016/03
  • 音響と採集具によるスケトウダラ稚魚に対するFMTの採集効率の推定  [Not invited]
    LU Zhen, 飯田浩二, 向井徹, 藤森康澄
    海洋音響学会研究発表会  2015/05
  • 音響カメラを用いた定置網内でのゼニガタアザラシの行動観察の試み  [Not invited]
    越智洋介, 山崎慎太郎, 伊藤遼平, 川本雄平, 藤田薫, 藤森康澄, 桜井泰憲
    日本水産学会大会  2015/03
  • 北海道えりも地域のサケ定置網におけるゼニガタアザラシによる食害防除を目的とした漁具改良の検討  [Not invited]
    藤森康澄, 川本雄平, 小林由美, 伊藤遼平, 桜井泰憲, 山本潤, 三谷曜子, 蔵本洋介, 関口泰治
    日本水産学会大会  2015/03
  • フレームトロール(FMT)によるスケトウダラ稚魚採集における網地色の影響  [Not invited]
    田谷惣一郎, 藤森康澄, 向井徹, 清水晋
    日本水産学会大会  2014/09
  • 仙台湾におけるアカガイを対象とした貝桁網の網目選択性  [Not invited]
    楠元彩香, 渡邊一仁, 藤森康澄
    日本水産学会大会  2014/09
  • CFD解析を用いた複葉型オッターボードの最適化  [Not invited]
    高橋勇樹, 藤森康澄, 木村暢夫
    日本水産学会大会  2014/03
  • 北海道東部えりも岬の秋サケ定置網におけるゼニガタアザラシの食害  [Not invited]
    小林由美, 桜井泰憲, 藤森康澄, 小林万里
    日本水産学会大会  2014/03
  • 高揚力オッターボード(HLTD)の流体力特性のCFD解析  [Not invited]
    沈暁麗, 胡夫祥, 塩出大輔, 東海正, 高橋勇樹, 藤森康澄, 木村暢夫
    日本水産学会大会  2014/03
  • 1950年‐2010年における東アジアのマグロ漁業の生産・貿易量の変動  [Not invited]
    劉 昱謙, 藤森康澄
    日本水産学会支部大会  2013/12
  • マアジ稚幼魚調査用表中層トロールにおける曳網条件と網口形状の関係  [Not invited]
    小堺真理子, 志村健, 藤森康澄, 向井徹
    日本水産学会北海道支部大会  2013/10
  • 鳥取県沖合底曳き網(かけまわし)のハタハタに対する選択性マスターカーブの推定  [Not invited]
    楠元彩香, 藤森康澄, 倉長亮二, 志村健
    日本水産学会大会  2013/09
  • 若狭湾における数種の藻場の音響反射特性  [Not invited]
    石田太朗, 安間洋樹, 南憲史, 道家章生, 西垣友和, 宮下和士, 藤森康澄
    日本水産学会大会  2013/09
  • CFD解析によるハイブリッド型風車の開発  [Not invited]
    廣龍太朗, 高橋勇樹, 幣寛樹, 藤森康澄, 安井肇, 足立伸次, 木村暢夫
    日本水産工学会学術講演会  2013/05
  • 汎用デジタルカメラを用いた水中下での魚体サイズ計測  [Not invited]
    藤森康澄, 山本潤, 木村暢夫
    日本水産工学会学術講演会  2013/05
  • CFD解析による複葉型オッターボードの流体力特性  [Not invited]
    高橋勇樹, 藤森康澄, 胡夫祥, 沈暁麗, 木村暢夫
    日本水産工学会学術講演会  2013/05
  • 鳥取県における沖合底曳き網(かけまわし網)のハタハタに対する網目選択性の解析  [Not invited]
    楠元彩香, 藤森康澄, 清水晋, 倉長亮二, 志村健
    日本水産工学会学術講演会  2013/05
  • マアジ稚幼魚を対象とした表中層トロール調査における採集量の変動要因  [Not invited]
    小堺真理子, 志村健, 藤森康澄, 向井徹
    日本水産学会大会  2013/03
  • オッターボード開発へのCFD解析導入の可能性について  [Not invited]
    高橋勇樹, 藤森康澄, 胡夫祥, 沈暁麗, 木村暢夫
    日本水産学会大会  2013/03
  • 金銀好, 向井徹, 藤森康澄, 飯田浩二
    日本水産学会大会講演要旨集  2012/09
  • 山内 繁樹, 峰 寛明, 林田 健志, 武田 康孝, 清水 晋, 藤森 康澄, 木村 暢夫
    日本水産工学会学術講演会講演論文集  2012/05
  • 張敏, 佐々木剛生, 門脇政輝, 藤森康澄, 安間洋樹, 前川和義, 木村暢夫
    日本水産学会北海道支部大会講演要旨集  2012
  • 高橋勇樹, 藤森康澄, 坂岡桂一郎, 渡邉豊, 木村暢夫
    日本水産学会大会講演要旨集  2011/09
  • 山内繁樹, 峰寛明, 林田健志, 石坂紀子, 清水晋, 藤森康澄, 木村暢夫
    日本水産学会大会講演要旨集  2011/09
  • 藤森康澄, 若山賢一, 平野和夫, 石田良太郎
    日本水産学会大会講演要旨集  2011/03
  • 加藤良平, 安部智貴, 金子拓未, 木村暢夫, 藤森康澄, 安井肇, 井尻成保, 足立伸次
    日本水産学会北海道支部大会講演要旨集  2011
  • 山内 繁樹, 峰 寛明, 林田 健志, 清水 晋, 藤森 康澄, 木村 暢夫
    日本水産工学会学術講演会講演論文集  2010/05
  • 山内 繁樹, 峰 寛明, 清水 晋, 藤森 康澄, 木村 暢夫
    日本水産工学会学術講演会講演論文集  2010/05
  • 安田 研也, 高橋 秀行, 藤森 康澄, 木村 暢夫
    日本水産工学会学術講演会講演論文集  2009/05
  • 山内 繁樹, 櫻井 泉, 金田 友紀, 清水 晋, 藤森 康澄, 木村 暢夫
    日本水産工学会学術講演会講演論文集  2008/05
  • 人工漁礁の規模と単位漁獲の変化  [Not invited]
    平成20年度日本水産工学会学術講演会講演論文集  2008
  • 若山 賢一, 田上 陽之, 藤森 康澄, 木村 暢夫, 三浦 汀介
    日本水産工学会学術講演会講演論文集  2006/06
  • 佐久間 康平, 木村 暢夫, 藤森 康澄, 阿部島 直哉
    日本水産工学会学術講演会講演論文集  2006/06
  • 齊藤 二郎, 村井 克詞, 佐藤 亘, 川西 健孔, 岩岡 正浩, 木村 暢夫, 岩森 利弘, 藤森 康澄
    日本水産工学会学術講演会講演論文集  2006/06
  • 大杉 康則, 木村 暢夫, 藤森 康澄, 阿部島 直哉, 岩森 利弘
    日本水産工学会学術講演会講演論文集  2006/06
  • TAKAHASHI YUICHIRO, FUJIMORI YASUTO, HONDA SATOSHI, OZEKI YOSHIOKI
    日本水産学会大会講演要旨集  1996/03
  • Floatline height and netting shape of semi-trammel net set across a current  [Not invited]
    Proceedings of the 2nd Asian Fisheries Forum, Asian Fisheries Society, Manila, Philippines  1990

Association Memberships

  • 日本水産学会   日本水産工学会   水産海洋学会   

Works

Research Projects

  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2020/07 -2026/03 
    Author : 山口 篤, 松石 隆, 向井 徹, 藤森 康澄, 別府 史章
     
    今年度はかいあし漁業の内容を広く一般に普及させるための情報発信を主に行った。国内学会の発表2件に加え、Fish of the Month (FoM) という、北海道大学水産学部の研究成果を紹介するHPにおいて、本科研費の研究分担者を主とする5名による、かいあし漁業に関する内容を紹介した。紹介内容と紹介者は以下の通りである:「海洋生態系におけるカイアシ類の重要性とかいあし漁業への夢(山口 篤)」、「カイアシ類の音響探知(向井 徹)」、「カイアシ類の音響散乱特性(福田美亮)」、「カイアシ類を対象とした商業漁業(藤森康澄)」、「カイアシ類-新たな水産脂質供給源として(別府史章)」。 カイアシ類を対象とした研究論文として、北太平洋亜寒帯域に優占する日周鉛直移動を行うカイアシ類Metridia pacificaの一次生産への摂餌インパクトを推定し、呼吸量による輸送量の推定を行った。これは、表層(0-50 m)と深海(50-200 m)の水温条件下において、同種の雌成体を飼育し、呼吸による酸素消費量を測定し、現場の表層における摂餌量の推定と、深海における呼吸による炭素輸送量を推定したものである。夜間の表層における個体数は1平方メートルあたり27~5422個体の間にあり、昼間の表層には本種は出現せず、これは日周鉛直移動の反映と考えられた。日周鉛直移動バイオマスは、1平方メートルあたり1-309 mg Cであった。1日の夜間表層と昼間深海での滞留時間を考慮すると、1日あたり1平方メートルあたりの摂餌量は0.04-11.04 mg Cと推定され、これは現場一次生産量の0-2.4%を占めていた。一方、昼間深海での1日あたり1平方メートルあたりの呼吸量は0.02-9.39 mg Cと計算された。これは有光層からの沈降粒子輸送量の0-10%に相当しており、物質循環における重要性が示された。
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2022/04 -2025/03 
    Author : 藤森 康澄, 富安 信
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2018/04 -2021/03 
    Author : Fujimori Yasuzumi
     
    This study investigated a method to improve selectivity of shrimp pot aiming to protect the stock of Coonstripe shrimp Pandalus hypsinotus in the Funka-Bay, Hokkaido. It was found that small individuals were particularly active at night from the water tank experiment to investigate the behavior and diurnal activity. This suggested mesh size expansion and the installation of escape gap on pot for exclusion of small shrimp would be effective. The mesh selectivity of the pot was estimated by water tank experiments, and it was elucidated that 35 mm mesh size was suitable to protect individuals with 20 mm carapace length which correspond to the size of recruitment. Also, we confirmed that the circular escape gap with an inner diameter of 25 mm was expected to exclude the carapace length of 30 mm which correspond to the size after sexual conversion.
  • 平成30年度 えりも地域ゼニガタアザラシ行動解析調査業務
    環境省:環境省北海道地方環境事務所受託研究
    Date (from‐to) : 2018/11 -2019/03 
    Author : 藤森 康澄
  • H29スルメイカ対光行動実験の実施に係る委託事業
    国立研究開発法人水産研究・教育機構・水産工学研究所:受託研究
    Date (from‐to) : 2017/04 -2017/12 
    Author : 藤森 康澄
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (A)
    Date (from‐to) : 2012/04 -2017/03 
    Author : Yamaguchi Atsushi
     
    From both viewpoints of fisheries and oceanography, zooplankton size structure is a prime important factors to determine their flux. Concerning zooplankton size spectra, following four topics were evaluated: 1. Spatial distribution of neighboring water of Japan, 2. Geographical distribution in the North Pacific, 3. Vertical distribution down to greater depths covering whole North Pacific, 4. Yearly changes (1946-2012) in the Chukchi Sea. Concerning energy transfer within the zooplankton community, bottom-up control and high energy transfer efficiencies were observed for the western subarctic Pacific. In the western subarctic Pacific, zooplankton community was dominated by large-sized copepod Neocalanus spp. For vertical distribution, regional differences in zooplankton community were recognized even in the deep-sea down to 2000 m. Inter-annually, zooplankton biomass in the Chukchi Sea increased through 1946-2012.
  • 平成28年度 えりも地域ゼニガタアザラシ捕獲網の 改良検討業務
    環境省:環境省北海道地方環境事務所受託研究
    Date (from‐to) : 2016/04 -2016/10 
    Author : 藤森 康澄
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2013/04 -2016/03 
    Author : TOKAI Tadashi, HU Fuxiang, SHIODE Daisuke, KAWABATA Atsushi, FUJIMORI Yasuzumi
     
    A drift net series consisting of several net panels of different mesh sizes was used to investigate pelagic fish resources in the waters around Japan. First, mesh selectivity of research driftnet for Japanese sardine was estimated. The relationship of body girth against the mesh perimeter suggested that Japanese sardine was efficiently caught by the capture process of “wedged” or “gilled”. Next, selection curves of research driftnet for chub mackerel were estimated in the two periods of June-July and September-November. Fish caught in June-July had slightly greater fork length than those in September-November, and they also had a lower condition factor implying a smaller body girth following spawning. The pooled relative catching intensity steeply declined for fish with fork length over 300 mm at the current mesh combination, and the addition of two panels with larger mesh sizes (82 and 106 mm) kept a constant intensity for fish below 350 mm fork length.
  • 潮沿岸域のゼニガタアザラシと 沿岸漁業の共存に向けた保護管理手法の開発
    環境省:環境研究総合推進費
    Date (from‐to) : 2013/04 -2016/03 
    Author : 桜井泰憲, 藤森康澄, 宮下和士, 山本潤, 三谷曜子, 小林万理, 山村織生, 服部薫
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research Grant-in-Aid for Scientific Research (C)
    Date (from‐to) : 2012/04 -2015/03 
    Author : FUJIMORI Yasuzumi, YAMAMOTO Jun
     
    This study aims to develop a new method of measuring the size of fish on the image from camera. The tank experiment was conducted using a digital camera and laser unit that generate flat beam. Further, sea experiment was done preparing a measuring system installed to watertight case that has capability of 300 m sea depth. The measurement error was 4 % in mean and up to 5 % in the tank experiment. In the sea experiment, the measuring system was hanged underwater from the ship. The fish that recognized as walleye pollock was observed. The estimated length accorded with the size of walleye pollock distributed in the experimental area.
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2011/04 -2014/03 
    Author : MIYASHITA KAZUSHI, FUJIMORI Yasuzumi, KIMURA Nobuo
     
    In coastal area, Sargassum spp., Zostera spp. and Laminaria spp. forms dense vegetation community, which are called as seaweed bed, seagrass bed and kelp bed. In this study, we estimated the characteristics and the wave shapes of acoustic intensity of these beds, and then we developed the discriminate method of these beds by acoustic technique using the characteristics. In the result, it was suggested that the discrimination of the beds is possible using a two-stage approach. The first stage is the discrimination of the area backscattering (Seaweed bed; -33.3~-57.0 dB, Seagrass bed; -39.2~-66.1 dB, Kelp bed; -59.8~-74.3 dB). In the second stage is the discrimination of the wavelet coefficient of Lv. 4 (Seagrass bed; 12000-39000, Kelp bed; 3000-12000). This method may allow better biomass estimation of these beds by acoustic technique.
  • 海生哺乳類による漁業被害低減に向けた生態解明と混獲防止技術に関する研究:Ⅱ音響ピンガーを用いた混獲防止手法に関する研究
    公益財団法人 北水協会:水産学術研究・改良補助事業
    Date (from‐to) : 2010/04 -2012/03 
    Author : 藤森 康澄
  • Japan Society for the Promotion of Science:Grants-in-Aid for Scientific Research
    Date (from‐to) : 2009 -2011 
    Author : HU Fuxiang, TOKAI Tadashi, SHIODE Daisuke, HUJIMORI Yasuzumi
     
    In this research, the new multi-sampling trawl with automatic net opening and closing control system was developed to sample pelagic juvenile fish. A net-release controller is used, which not only controls the net release mechanism but alsorecords the net depth, temperature and flow rate during net towing. The field experiment was carried out using training ship Shinyo-maru, and RV Kaiyo-maru in Sagami Bay. From the results, the net maintained almost constant depth under towing speed from 2. 0-4. 0kt, and the nets were surely opened/closed smoothly by the command from the controller. The newly developed multi-sampling trawl is considered to be suitable for quantitative layer sampling of juvenile fish.
  • 天皇海山における底生生物調査用採集具の設計・製作
    水産総合研究センター:受託研究
    Date (from‐to) : 2008/04 -2010/03 
    Author : 藤森 康澄
  • 燃料経費削減のためのシラス魚群マップ即日配信システムの開発
    農林水産省:農林水産研究高度化事業
    Date (from‐to) : 2007/04 -2010/03 
    Author : 宮下 和士
  • 北海道におけるハタハタ刺網の網目選択性の推定
    公益財団法人 北水協会:水産学術研究補助事業
    Date (from‐to) : 2007/04 -2009/03 
    Author : 藤森 康澄
  • Ministry of Education, Culture, Sports, Science and Technology:Grants-in-Aid for Scientific Research(基盤研究(B))
    Date (from‐to) : 2002 -2004 
    Author : Yasuzumi FUJIMORI, 向井 徹, 山下 成治
     
    This study is consist of two kinds of categories as shown below.1.Development of automated opening/closing system for WYSIWYG-Net: Automated opening/closing system to achieve the multi-layer sampling for plankton and micro-nekton was developed. This system could be worked without an armored cable winch system and allows to conduct multi-layer sampling on any research vessel.2.Utilization of LOPC (Laser Optical Plankton Counter) with net : The platform unit was made for zooplankton sampling with LOPC and the data from the net and LOPC were compared. From these results, the methods to estimat...
  • Ministry of Education, Culture, Sports, Science and Technology:Grants-in-Aid for Scientific Research(基盤研究(A))
    Date (from‐to) : 2001 -2003 
    Author : Sei-ichi SAITOH, 三浦 汀介, 飯田 浩二, 向井 徹, 藤森 康澄, 米田 國三郎
     
    It is very important that we develop multi-dimensional sensing in combined with satellite remote sensing, underwater remote sensing and direct survey to predict when, where and how much are marine living resources available. Objectives of this study are to develop methodology of multi-dimensional sensing of marine living resources and their environment and to monitor three-dimensional distributions of Japanese common squid and three dimensional environment using acoustic with towed body transducer and real-time towing CTD system with satellite images. Major results are as follows :(1)Observ...
  • 日本学術振興会:科学研究費助成事業 特定領域研究(A)
    Date (from‐to) : 1998 -1998 
    Author : 三浦 汀介, 藤森 康澄
     
    イカ残滓の有効利用技術の現状 我々の研究グループが行っているイカゴロを釣の人工餌料として活用する試みもその一つである。鹿児島大学水産学部との協力で、キンメダイやメヌケなどを対象に近海・沿岸漁業での応用可能性について調査を始めた。また、北海道大学水産学部では、ハワイ沖漁場でマグロの延縄の試験操業を行い、代替飼料としての可能性を調査した。遠洋漁業の代表とも言えるマグロ延縄漁業は、年間、6万トンほどの天然餌料(イカ、サンマなど)を消費している。一方、遊魚の餌としての利用も始まった。これらの利用方法が確立すれば、道南のイカゴロ問題解決策の重要な決め手となる。青森では、以前からイカ墨の抗腫瘍性の研究が進み、イカ墨利用の各種食品の開発が進んだ。また、イカの皮から染色材を抽出する研究も進行中である。北大工学部では、イカの骨からとったキチンを利用して人工皮膚の研究も進んでいる。 現在進行中の企業化プラン(イカ墨染めの特産品化) イカゴロから釣餌を造る過程で廃棄されるイカ墨を利用して、特産品(アート・工芸品)の開発を試みる計画である。釣餌を製造する株式会社コーノがその生産過程でイカ墨を排出する。これを使って蕃伎社を支援して最終的に函館市の特産品化を目指すものである。 今後の計画 函館市商工観光部の呼びかけでイカの加工から消費にいたる過程で関わる地域の関係者を集め、現状の課題や今後の産業起こしを目指して、相互に情報・意見の交換を行うことを目的に、仮称“いかゼロエミッション調査研究会"の発足準備が進められている。参加者は北海道大学水産学部、道立工業試験センター、水産加工組合、関連企業、自主研究グループ、市関係部局が中心に、平成11年度、年5回程の会議が予定されている。 以上、今年度は当初計画していたイカ残滓有効利用技術の現状把握に加えて未来型技術の提案について、ならびに来年度に向けての具体的な成果を得ることができた。
  • 沿岸漁業の効率化のための情報科学の応用
  • Survey techniques and data analysis for marine fish resources, Application of infromatics for developing coastal fisheries.

Industrial Property Rights

Social Contribution

  • 中堅教諭等資質向上研修(高等学校)
    Date (from-to) : 2017-2019
    Role : Lecturer
    Sponser, Organizer, Publisher  : 北海道教育委員会
  • 「はこだてイカマイスター」養成講習会
    Date (from-to) : 2012-2019
    Role : Lecturer
    Sponser, Organizer, Publisher  : 函館水産物マイスター養成協議会


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