文献一覧: 島崎健二 (著者)

2 0 0 0 OA オホーツク海北部における夏季のニシンの分布および生物学の特徴について

著者: 高橋豊美上野元一島崎健二
出版者: 公益社団法人日本水産学会
雑誌: 日本水産学会誌 (ISSN:00215392)
巻号頁・発行日: vol.39, no.7, pp.759-764, 1973-07-25 (Released:2008-02-29)
参考文献数: 11

Though many biological studies have been made on the commercial-sized herring, Clupea harengus pallasi, in the northern part of the Okhotsk Sea in summer, knowledge on the dis-tribution and biological characteristics of the juvenile in the same period is inadequate even today. The authors studied informations obtained from the measurements of about 2400 samples. The samples were obtained by surface gill nets, varying in mesh size from 30mm to 82mm, used for capturing juvenile salmon, and the samplings were conducted on the research vessel “Oyashio Maru” in the northern part of the Okhotsk Sea from August 17 to September 3, 1971. The results obtained are summarized as follows: 1) The shoals, composed of middle and large-sized fish (20-33cm) were found in the area off the Koni Peninsula, the small-sized fish (12-15cm) in the area off the Okhotsk, and the medium-sized fish (18-26cm) in the area off the Ayan. The area, where each shoal appears, seems to vary yearly. 2) The fish of 2-3 age were observed in comparative warm waters (13-14°C) in 1971, 12-13°C in 1970 (Unpublished data). 3) Samples of the 4 age, caught in the area off the Ayan, were smaller in their average fork length, and heavier in the ratio of body weight to fork length, and higher in the mean maturity index {gonad weight×102/(body weight-gonad weight)} than those from the area off the Koni Peninsula. There is a possibility that the fish in the area off the Ayan may not belong to the Okhotsk population.

2016-05-27 08:02:07
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1 0 0 0 OA 北西太平洋における冬季のサケ・マス分布

著者: 島崎健二中山信之
出版者: 北海道大学水産学部
雑誌: 北海道大學水産學部研究彙報 (ISSN:00183458)
巻号頁・発行日: vol.26, no.1, pp.87-98, 1975-06

2020-05-01 13:29:40
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http://hdl.handle.net/2115/23549

1 0 0 0 OA 夏季の中部北太平洋におけるサンマの成熟と日齢

著者: 巣山哲桜井泰憲島崎健二
出版者: 日本水産学会
雑誌: 日本水産学会誌 (ISSN:00215392)
巻号頁・発行日: vol.62, no.3, pp.361-369, 1996-05-15
被引用文献数: 13

The maturation process and age in days of female Pacific saury Cololabis saira (Brevoort) in the central North Pacific Ocean were examined based on histological observations and otolith daily growth increments. The maturation process of Pacific saury used in this study (243-342mm in knob length) was divided into 6 stages: early yolk vesicle stage, late yolk vesicle stage, yolk formation stage, maturation stage, atretic stage I, and atretic stage II. Atretic stage fish were considered to be post-spawning as many degenerated oocytes were observed. The large size group (more than 296mm), in which fish were more than 1.5 years old as estimated from daily growth increments in otoliths, contained spawning and post-spawning individuals, although all individuals from the medium size group (241-295mm), from 10 months to 1 year and 3 months old, were immature. Since post-spawning fish were seen to have recovered their initial condition factors, it is suggested that they survive beyond the first spawning season. Based on observations of asynchronously developing oocytes, it is considered that Pacific saury spawn several times during a single spawning season.

2020-03-12 03:22:22
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1 0 0 0 OA 雄スルメイカの成熟にともなう精巣および付属腺の発達について

著者: 池田譲桜井泰憲島崎健二
出版者: 公益社団法人日本水産学会
雑誌: 日本水産学会誌 (ISSN:00215392)
巻号頁・発行日: vol.57, no.12, pp.2237-2241, 1991-12-25 (Released:2008-02-29)
参考文献数: 15
被引用文献数: 9 12

Development of male reproductive organs during sexual maturation was studied for Japanese common squid caught from feeding and spawning grounds. The male maturity was divided into five stages based on the histological observation of the testis. The maturity was compared with testis somatic index (TSI: testis weight as a percentage of body weight) and accessory gland somatic index (AGSI: accessory gland weight as a percentage of body weight). Results showed that sperm have already been produced in the testis even when the testis is a relatively small size, and that the male maturational process consists of two phases. In the first phase, sperm are produced in the testis and in the next phase sperm are transferred into the accessory gland, stored there in the form of spermatophore until copulation with the female. In the maturation stage, sperm are still produced, which means that copulating behavior is repeated by same male during this final sexual stage. It is possible to express the male maturity condition by TSI and AGSI. These numerical values are TSI>0.5 and AGSI>0.1 in the maturing stage; TSI>2.0 and AGSI>l.0 in the mature stage.